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Discussion Starter · #1 · (Edited)
HI, all. Looks like the forum is dead, but in case anyone can provide me some info, that would be great.

From all the research I could find here the VJ11 and T-bird VC32 share the same exhaust wheel dimensions, but the compressor wheel of the t-bird is larger by about 3mm (39mm vs 36mm for VJ11). I stumbled on a billet wheel that has the following measurements:

Nose Dia: 10.00 mm
Inducer Dia. : 40.00 mm
Exducer Dia. : 52.50 mm
Extend Tapered Tip Exducer Dia. : 56.02 mm
Tip Height: 4.05 mm
Super Back Height: 0.00 mm (Flat Back)
Overall Height: 22.60 mm
Bore Size : 5.10 mm
STD or customs size : Custom size
Blade : 5+5
Trailing angle : 60 Degree
Bore Type : Through
Fits OE Comp Hsg : Modification required on OE comp housing
Cutback : 0.0
Rotation : Forward

I assume this is a shoe-in with potential minimal machining of the housing, since this one is allegedly 1mm wider.

Thoughts?

Edit: just found the wheel dimensions for T-bird VC-32 from IHI and VJ11:

I wonder how precise those guys are with their 40mm inducer.
Inducer "ØA"
Tip Height "B"​
Exducer "ØC"
Hub Length "D"​
Bore "ØE"​
Trim/No. of blades​
Style​
Inches​
1.625​
0.190​
2.068​
0.950​
0.201​
62 trim/5-5​
Flatback​
Milimeters​
41.28
4.83​
52.53
24.13​
5.11​



I H I to Turbo International 039T-049 3-F-1295 COMPRESSOR WHEEL BR4219E RHB5


13467


 

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Discussion Starter · #2 ·
Been chasing a few manufacturers out of China/Taiwan, as well as U.S. The options are there and don't cost much if there is enough interest. Lowest quantity I got so far is 5 units for $55 each with $35 shipped to my door (lead time 4-6 wks). That was from mambatek (reputable ebay seller). Otherwise that 40mm wheel is readily available on ebay as well. Let me know if anyone is interested.
 

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Discussion Starter · #4 ·
Small vs what? I've put close to 200 wheel on a mustang dyno on my VJ11 on less than 10 pounds of boost. When I put a t-bird in, it was a night and day difference at the same boost level (i do need to get retuned, as was running a bit lean). I am running this on a ZX2, not a MX6, so it might be different. T-bird was a straight bolt-on vs trying to figure out new mani and piping for a T3/4 or whatever else. Got one for $250, but turned out to be a lemon, leaking from the turbine side, so was researching the wheels to slap on my good VJ11 (and balance it) and re-use the tbird comp housing. Couldn't find any manufacturer's specs on the forum, so really just sharing what I found.
 

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I run a t-bird wheel on my Probe. There is just as much work with the t-bird wheel as a T3 turbo. From what I read above it sound like you are trying to machine the housing of the VJ11. That is waste of time. You need the t-bird cold side housing to make it worth it, and you need to manufacture an o2 housing. It would also be a good idea to port the exhaust turbine housing to the new o2 housing. You still want to replace your fuel pump to a Walbro 190 or 255. Not to mention downpipe and the rest of the exhaust. The T-bird hybrid is still running a 52 mm turbine vs. a 60 mm turbine of a Garrett T3 50 or 60. I have squeezed out every bit of hp out my T-bird setup. It does flow nicely with a A/R of something like .76. The cfm of F2T stock matches really nicely with the setup across the rpm band from 1st through 5th. You can get a lot more hp out of larger turbine turbo, but for a daily driver the setup work nicely. Not to mention you won't have to worry about going standalone with the setup. I do have a aftermarket chipped ECU (it has been so long that I cannot remember which chip). However, this was mostly for doing away with the fuel cut.







 

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Small vs what? I've put close to 200 wheel on a mustang dyno on my VJ11 on less than 10 pounds of boost. When I put a t-bird in, it was a night and day difference at the same boost level (i do need to get retuned, as was running a bit lean). I am running this on a ZX2, not a MX6, so it might be different. T-bird was a straight bolt-on vs trying to figure out new mani and piping for a T3/4 or whatever else. Got one for $250, but turned out to be a lemon, leaking from the turbine side, so was researching the wheels to slap on my good VJ11 (and balance it) and re-use the tbird comp housing. Couldn't find any manufacturer's specs on the forum, so really just sharing what I found.
Small vs most turbo's worth upgrading to.
Running a Zetec 2L high compression and high revving engine these IHI's may be enough turbo to complement the engine.

The info you posted is appreciated, 15years ago you would have tons of people trying to place orders with you.
Your idea of night and day must be very different than mine or the T-bird turbo magically doubles the power output of the zx2 at the same boost. And it should be day and night, day is pleasant to the average masses, night is associated with wicked, evil, mean and nasty, making factory power with a car is day doubling that in that car with that engine is night.

(I will use HP as an measurement because people seem to relate to it easier than torque numbers even though it's a meaningless number)

The F2T 7.8:1 2.2L with 94mm stroke is a very different engine, it puts down roughly 100hp at the wheels without boost. Making any decent power with an F2T means most of it comes from forced induction. The IHI turbo adds about 45 whp at factory boost, it's output can be doubled at best 90 whp before it explodes or snaps the turbine shaft. The IHI VJ11 is limited by it's turbine RPM, the higher the turbine rpm the higher the boost. Turbine RPM is regulated by the amount of exhaust gas flowing through it which is a direct result of the amount of air burned in the engine. The problem with the T-Bird, VJ11, VF11, VU10, VU11 .... is the RHB5 turbine and center section they all share, so at X shaft speed or boost or exhaust flow or air consumption they all blow up. To make 200 whp on the F2T requires doubling the block power with boost, which is a lot to ask from a little RHB5 if it could flow enough air to manage this than the F2T would put down 262 lb-ft torque at the wheels at 3800rpm making people with 300whp scratch their head wondering why they lost to 200whp.

The VU10 -VU11 IHI RHB5 turbo's, these are the same size or smaller than the VJll turbo, they come factory on a V8 2.9L engine that makes 477hp and 426lb-ft, this is the Ferrari F40. The bulk of the F40's power comes from the engine and the turbo's complement the engine, these tiny IHI's are at their limit on the Ferrari engine because Ferrari doesn't leave much room for modification or because ferrari tries to get as much out of a motor as safely possible. The F40 block runs 7.7:1 engine compression but has a 69.5mm stoke and 7750rpm redline, dual overhead cams and 4valves per cylinder. Factory boost is 16psi people raise the boost to 17psi, it is said 22psi can be run momentarily which sounds about right for a VJ11 on a 323 1.6L engine (of course Ferrari flows more air per displacement than the 323).
Even on the Ferrari's the RHB5 is the limiting factor to making more power.
---------------------------------

Your post does leave me wondering however. You state you made 200whp at less than 10psi boost with the VJ11 then upgraded to the T-bird turbo.

Lets say the T-bird turbo gave you 215whp at the same boost as the vj11, this would mean 7.5% more air from the T-bird and 7.5% more exhaust passing through the wastegate to maintain the same turbo shaft speed and boost pressure. If the VJ11 was at it's flow limit when you upgraded turbos this would all make sense but the VJ11 isn't near it's limit.
So to match the T-bird turbo's air flow the VJ11 needs to run more exhaust trough the turbine and less through the wastegate, simply run more boost. More boost does not mean more load on the engine as a matter of fact at the same boost on the T-bird the cylinder pressure was higher.

Example:
the VJ11 is rated to flow 21lbs per minute of air, lets say at 10psi you make 200hp. Now take a turbo rated to flow 42 lb/m air and run 5psi to make 200hp. The only difference is the turbine shaft speed and the amount of heat the compressor generates at higher boost, if the intercooler manages the same intake air temp on both turbo's than there is no difference in air volume or cylinder pressure at 5psi or 10psi.
A more simple example is your filling your tire with air you have two air compressors one has a large hose and runs at 100psi the other has a small hose and runs at 200psi. Both compressors take exactly 60 seconds to fill the flat tire from 0 to 34 psi. This means both compressors flow the exact same CFM or LB/M regardless of what pressure the compressors operate at the tire received the same amount of air in the same amount of time, to the tire there is no difference.

Air Volume = HP, Air Volume = Cylinder pressure. If at 2psi you get X CFM and make 200hp and cylinder pressure = X, If at 20psi you get the same X CFM you will make the same 200hp and have the same cylinder pressure.

This is where using horsepower as a unit of measure becomes a problem. Basic math would say 21lb/m would be good for 210 block HP, but like I said at the beginning Horsepower is a meaningless number, the F40 is passing 238.5 hp worth of air through each turbo. But because hp is calculated based on torque and represents work done over 1 minute at that torque and RPM. Torque is a direct representation of air flow at rpm.

If the 2.2l can run 16psi on the VJ11 before the exhaust volume overwhelms the turbine.
The 1.6l 323 can run 22psi on the VJ11 before the exhaust volume overwhelms the turbine.
The VJ11 should run up to 17.6psi on the 2.0L Zetec before the exhaust volume overwhelms the turbine.

For the 3 above engines at that boost the T-Bird isn't much of an upgrade because the RHB5 shaft is the weak point, logically any extra air/exhaust from the larger T-Bird compressor at the same psi will exhaust through the wastegate and the turbine shaft would spin at the same rpm. but the larger compressor wheel moves more air per RPM and air is the only resistance the turbine shaft has to overcome (within the limitation of exhaust flow), the more air that's moved the more strain on the turbine shaft.

The bottom line :
Any F2T driver who maxed out the VJ11 and upgraded to a T-Bird was left disappointed.
Any F2T driver running 12 or 13psi and upgraded to a T-bird but ran the same boost 12 or 13psi wasted their time and money.

I run a t-bird wheel on my Probe. There is just as much work with the t-bird wheel as a T3 turbo. From what I read above it sound like you are trying to machine the housing of the VJ11. That is waste of time. You need the t-bird cold side housing to make it worth it, and you need to manufacture an o2 housing. It would also be a good idea to port the exhaust turbine housing to the new o2 housing. You still want to replace your fuel pump to a Walbro 190 or 255. Not to mention downpipe and the rest of the exhaust. The T-bird hybrid is still running a 52 mm turbine vs. a 60 mm turbine of a Garrett T3 50 or 60. I have squeezed out every bit of hp out my T-bird setup. It does flow nicely with a A/R of something like .76. The cfm of F2T stock matches really nicely with the setup across the rpm band from 1st through 5th. You can get a lot more hp out of larger turbine turbo, but for a daily driver the setup work nicely. Not to mention you won't have to worry about going standalone with the setup. I do have a aftermarket chipped ECU (it has been so long that I cannot remember which chip). However, this was mostly for doing away with the fuel cut.
You did a good job, but I have to say that you should have went with the T3.
For me it was more work to pull the VJ11 from the manifold, extract the studs from the manifold, helicoil and replace the studs and torque to yield nuts, port the turbine housing and O2 housing and reassemble/reinstall everything than it was to install a T3 turbo.
99blkzx2 has the compressor housing for the T-bird.
I have killed dozens of VJ11 turbo's, 4 T-bird turbos and a VF11, over the years, running 17+psi (15+psi with a ported head) all on the factory fuel pump, injectors and FPR. With extra fuel I killed a Mitsu 14G at 22psi and a big 16G at 22psi.
In 2005 I installed my first T3, it was a 45trim .42a/r compressor from an 89 saab 9000 and was better that any of the IHI or Mitsu turbo's I ran before. I ran that saab T3 for many years on 2 different F2T cars up to 27psi boost until I upgraded to a couple of 60trim mustang T3's and a stage 3 T3 turbine/ T4 76trim. The 45 trim T3 is now sitting in my basement, it's 32 years old, spent 7 years running 21+ psi and has no more shaft play than it did when I took it off the Saab.
I have chipped factory ECU's on all my cars with piggyback extra injectors and have managed 30psi on a 60trim T3 without issues.

Going from IHI to Garrett for me was the difference between beating 300bhp cars on IHIs and beating 600bhp cars on the Garretts.

Like you mentioned "You have squeezed every bit of power out of this set-up" I can relate, trust me no longer being limited by the turbo on the car makes the whole car seem different, suddenly it has potential again, limited by fuel timing and physics is moving to the next step of tuning and modification .
I will have to disagree about the T-bird being the perfect turbo for the F2T, especially with the IHI wastegate. A stage 1 turbine T3 .48a/r with 45 trim .42a/r comp at 15psi on stock fuel system and computer is the way the F2T should have came, the initial sudden torque has a smoother band and higher peak, boost comes on as quickly as the VJ11 but pulls harder near redline, since running Garrett turbo's I have shredded 0 differentials, with IHI turbos I have shredded more than 13 differentials on way slower builds. On garrett turbos I have snapped 2 CV-joints, twisted the splines on oversized millennia 36mm nut axles end and shredded 3rd gear on two transmission (but I got plenty of gear assembly in the transmission with shredded differential), the drive train issues I have had with garrett turbo's are related to making too much power, all the IHI drive train issues where due to the power limiting IHI RHB5's funny little powerband.



I guess if anyone is interested I should have two usable T-Bird compressor housings and a complete ebay T-bird turbo that had too much to use, so it needs a rebuild or for the comp wheel and housing to be installed on a good RHB5 cartridge.
So I have T-Bird turbo parts at my shop, I don't want them and will never install them, can sell them but whenever anyone is looking for a T-bird turbo on MX6.com I tell them not to waste their time and install a T3 instead.

If after reading all this anyone still want's T-Bird parts I am not against recuperating some of the money I wasted on the T-bird turbo's. If I had a 2.3l Thunderbird and was just selling the turbo randomly I would have no guilt but after years of wasting my time working around IHI and Mitsu turbos being limited to make less that half the power I want out of the car because of the lump of shit bolted to the manifold, buying underdrive pulleys, aluminum flywheels, manual rack and pinions and doing tons of other mods many of which resulted less max boost before the turbo exploded, like a dog chasing it's tail leaving one spinning in circles getting nowhere.
 

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Discussion Starter · #8 ·
I'll just attach my VJ11 dyno run here so once I'm retuned with the t-bird, we can compare apples/apples. This was on a Mustang dyno, btw. I have since added an MBC and turned her up, which did produce noticeable gain, but was still choking out at higher RPM (obvious in the graph). It'd pull to 15 psi in higher gear (3-5) and hold 2nd pretty steady at around 9-10psi, but t-bird holds 2nd gear at 10+ per my gauge and keeps pulling thru the redline @7k, but running lean (around 12 afr). I never said the output was "doubled", just that it was really noticeable.

Upgrading to a Tx setup with a stock bottom end is currently not worth it to me. Again, I've paid $250 for the turbo, so bang/buck is definitely there for me. Shall the bottom let loose, I will then focus on building her up. Otherwise, I'll get to enjoy this car a bit more on the cheap.

I may be interested in your t-bird wheels/housing. Shoot me a pm with your asking price.

13499
 

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I'll just attach my VJ11 dyno run here so once I'm retuned with the t-bird, we can compare apples/apples. This was on a Mustang dyno, btw. I have since added an MBC and turned her up, which did produce noticeable gain, but was still choking out at higher RPM (obvious in the graph). It'd pull to 15 psi in higher gear (3-5) and hold 2nd pretty steady at around 9-10psi, but t-bird holds 2nd gear at 10+ per my gauge and keeps pulling thru the redline @7k, but running lean (around 12 afr). I never said the output was "doubled", just that it was really noticeable.

Upgrading to a Tx setup with a stock bottom end is currently not worth it to me. Again, I've paid $250 for the turbo, so bang/buck is definitely there for me. Shall the bottom let loose, I will then focus on building her up. Otherwise, I'll get to enjoy this car a bit more on the cheap.

I may be interested in your t-bird wheels/housing. Shoot me a pm with your asking price.

View attachment 13499
To start.

Lets see If we can improve the performance of the VJ11 and your set-up a bit.
The VJ11 wastegate sucks at holding steady boost at 2 times it's spring rate.
The first thing to do is port the wastegate hole in the turbine housing, having the hole larger helps keep the flap from getting pushed opened by exhaust pressure in the housing. Do you run a multi stage boost controller? or gear regulated boost control?

Wastegate boost signal source and boost control:

It is important to take boost signal readings from the charge pipe as close to the throttle body as possible and not from the compressor housing. If you ran only wastegate boost this wouldn't matter but because your running more boost than the wastegate is set to it really helps.

As boost builds in the compressor housing it starts to trigger the wastegate even before the pressure reaches the throttle body, this makes achieving set boost slower.

By taking boost pressure readings from the intake manifold (that reflects the pressure fed to the engine) but having the wastegate regulated by boost at the turbo the wastegate and engine aren't operating at the same boost pressure.
The more boost is raised above the wastegate actuator pressure the harder it gets to regulate, even Tial external waste gates suggest using a spring rate close to the desired boost to achieve steady boost.

So lets say the factory wastegate is 8psi and manifold boost is 7psi after the intercooler and charge pipe losses, your manual boost controller has to add 8psi to achieve 15psi manifold boost. But move the signal source near the throttle body and the 8psi wastegate will yield 8 psi manifold boost and the manual boost controller needs to add 7psi to achieve 15psi manifold boost. 1psi doesn't sound like much but it brings the manual boost controllers added boost 14% closer to the wastegate actuator spring pressure.

Manual boost control. A proper set-up is crucial to holding steady boost in every gear and through the RPM range.
These turbos hate (and so do I) ball and spring boost controllers, the sudden boost of the small turbo comes on too fast and leads to a boost spike at spool up then the pressure overwhelms the ball and spring and boost drops as rpms increase.
A simple adjustable bleed off valve is the best way to manage steady boost.

The best Boost Control Set-UP:
13500


I have been running this boost controller set-up on all my cars for years and even on VJ11s and factory wastegates managed 15psi in all gears at all rpms, no spike and no dips, exact consistent boost all the time.

On my 1988 626GT I am running a T3 60trim with internal adjustable wastegate actuator, saab 9000 factory wastegate flap housing and O2 housing, the wastegate rod is set to 15psi, the manual boost controller is set to 21psi and the stage 3 boost controller (Modified factory VJ11 boost solenoid) is set to 30psi. So I am doubling wastegate boost on an internal wastegate and maintaining perfect boost all the time. I am honestly surprised at how perfect boost is with this internal wastegate set up. My 89 mx6 GT set-up with 38mm tial and 2.5" O2 housing running a 1bar spring doesn't hold boost any better than the 626 set up.

-----------------------------

Now to argue and agree.

Turbo Price :
Which turbo cost 250$ US, the VJ11 your running now or the T-bird that grenaded?

-My first T-bird I bought off a friend who drove t-birds for 100$cnd, his new T-bird was the supercharged POS, he kept the 2.3L turbo from his last car but if he used it again he was running a mustang T3, the t-bird turbine housing has a ford T3 flange. Installing this turbo involved removing Tbird from the ford turbine housing, removing the the VJ11 from the car and turbine housing, sorting out the T-bird plumbing, fabricating an inlet for the compressor, swapping the wastgate actuator, clocking the compressor housing installing the Tbird in the Mazda turbine housing and putting it back in the car. This turbo ran 16psi for a few months, 1/4mile times and trap speeds where identical to running the VJ11 and I expected to get something more from the T-bird so I added 120 octane race fuel to the car and turned the boost up to 18psi got a couple 1/4mile runs with no gains and snapped the turbine shaft.

-The other 3 T-birds I bought on Ebay for about 150$ us each + shipping. 2 of them lasted 1 week and the third wasn't worth installing.

-The first T3 was from a junk yard (saab 9000), paid 100$ for the manifold, turbo, downpipe and all the hoses and plumbing (T3 45 trim). Cut the T3 flange off the saab manifold and welded it to the F2T manifold, had to buy 2x 1/4" NPT barbed fittings and coolant hose, Tap the oil inlet on the turbo to fit the mazda oil line fitting and cut the oil return pipe shorter. Used the saab O2 housing/downpipe (it's clock-able and passed in the same spot as the factory exhaust). This turbo install was less work than the T-bird swap.

-The same yard got a second saab 9000, so I grabbed everything a second time for 100$.

-I traded a Mistu 14 G someone gave me for a freshly rebuild Garrett T3 60trim for a mustang (free).

-When I first threw together the 88 626GT I used a T3 turbine housing that had a bunch of cracks in it, I seem welded all the cracks and resurfaced the housing, the wideband O2 sensor would register proper A/F's at idle but read atmosphere (21) under acceleration, innovate motorsports was convinced it was air getting into the turbine housing even though no pressurized exhaust was getting out, I felt it was a wideband issue but I already tried a different lc1 controller and gauge with the same bad readings. I found another T3 .48 A/R turbine housing for sale online in Toronto, the guy wanted 80$ and threw in the turbo that was on it for free (He planned on putting it on a F2T mazda 626 until it crashed, what are the odds).
The turbo that came with it was like new or brand new it's the T3 60trim that's on the 626GT now. (61% flow increase for free). Also the wideband problem was a faulty O2 sensor that was shorting out under boost pressure but wasn't throwing error codes. On this 60trim with water meth running 30psi the car beats a Lamborghini aventador lp 700 roadster with ease. 80$ turbo, 1300cc extra injector controller, home made water meth system 400cc 51/49 mix, factory timing, block and transmission.



4 IHI T-birds cost me 450$ us + shipping (35 -40$ each) + 100$ cnd = 0 smiles but lots of headaches and aggravations.
4 Garrett/air research turbo's cost me 280$ cnd + 20$ shipping = 0 aggravations, incredible reliability and never ending smiles.

Did you know the 45trim .42 A/R t3 is rated to flow 21lb/m and apparently so is the IHI VJ11, the first saab t3 install ran a VJ11 wastegate actuator and I used a bunch of throttle body spring between the waste gate actuator and flap to stiffen the actuator spring rate this hoaky wastegate set-up resulted in 27psi boost spikes in all mid range rpms and would tapper down to 22psi (boost controller settings) above 5600rpm, the car was lightning fast (faster than a z06)so I left it like that for a few years, driven daily and spooling all the time, when I prepared the custom O2 housing with external wastegate I cleaned up the 2nd junk yard 45trim because I could keep driving the car and figured the 45 trim that's on it must be getting worn out with all the abuse I'd been putting it through. When I swapped the turbos and housings and downpipes on the car to my amazement the turbo had less shaft play than when I installed years ago (bearings where dry then), so I put it on the 626GT.

-----------------------------


This is how I started my first post:
Running a Zetec 2L high compression and high revving engine these IHI's may be enough turbo to complement the engine.
And at no time did I recommend you change from rhb5 to T-series and within the RHB5 exhaust flow limit you would see power gains (i wouldn't call it 250$ worth).

You posted impartial information to share it with the MX6.com community, appreciated and respectable.

But remember this is the 1st gen mx6 section and most people in the force induction section run F2/F2T engines and I am discussing the merrit of the T-bird upgrade on the F2T engine that can max out the factory VJ11 turbo using a 20$ boost cut chip and a 10$ make shift boost controller, so for 30$ you get 8psi more boost (+- 45hp 60ft-lb) and anyone would expect that or more hp from a turbo upgrade.

I am not posting to discourage your project or turbo choice.
I am posting this so F2T drivers are informed about the T-bird turbo and it's gains on the 2.2l 12valve and don't make the same mistake poor Solarpwr and myself have doing all kinds of work around an RHB5 that will never flow enough air to make the F2T fast no matter how much money and work you throw at the car.

A turbo upgrade that shares similar issues with the T-bird upgrade is the Toyota CT-26 good for 300hp (rated for 35lb/m but can't flow that on an engine), because the turbine housing is unique to that turbo, some supra owners would have the ct-26 compressor side converted to a t4 60-1 compressor and housing rated to flow 550hp (55lb/m), way bigger jump than jv11 to T-bird but the damn Ct-26 turbine shaft, wheel and cartridge design resulted in very small gains before the turbos die (just over 15psi).

The Buick grand national comes with a Garrett TBO-348, it's rated to flow 37lb/m at 23psi but most push them to 27psi and with proper intake air cooling some have managed 40psi allowing gains of 150 -180 hp on the factory turbo.

But the real difference between the Garretts and the IHIs or Toyotas or Mitsus, They will continue to operate at much higher boost pressure than they are rated for, until they fall off the map and stop making power at witch point you turn the boost down a bit, continue enjoying the car while contemplating near limitless bolt on turbo upgrade combinations. With the ihi/toyota/mitsu turbo's finding the boost limit means you need to replace the turbo, ihi and toyota users have to source a cheap replacement just to drive the car while contemplating a custom upgrade, mistu user have upgrades available but still need a new turbo.
 

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As for the T-Bird I will have to check the compressor wheel and make sure it never contacted the comp housing, haven't looked at it in over 16years, If everything is good I would sell the turbo for 100$ + shipping, I also have 15+ good VJ11's to sell, F2t manifolds and O2 housings, need VJ11 parts I got 25 to 30 blown VJ11 some of which the compressor housing did not explode.
 

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I am tired of the rear seals of IHI vj11. I'm using a vj11 on a much smaller engine a 1.3 DOHC G13B Suzuki engine. Even with that engine I'm upgrading to a Turbonetics T3 50 F1-49 turbine that has an inducer size is 59 mm. Right now it has a lot of lag, but jumps like a rocket from 5000 rpms past the end of the speedometer at 130mph (it is only a 1850 lbs car, with a high revving engine). I simply am going to use a .48 A/R or a .63 A/R turbine housing to reduce the boost lag. Since the vj11 is actually something like a .76 A/R despite the larger turbine and slightly larger compressor it should work well. Just having different turbine housing to select from will make it worth it. I think the killer of the vj11 for the Mx6/Probe is no real oil cooler, and the crappy stock blow off valve ( the small shaft doesn't help). When I built the manifold below I used a T3 merge collector because I knew I wasn't going to stay with the vj11. Bringing a vj11 or t-bird hybrid above 18.5 psi is a waste of time and is going grenade the turbo. The air flow of a t-bird is higher than a vj-11 and I think if I put it on a dyno I could get 225 at the wheels, but that is with upgraded intercooler (evo 8), piping, complete 2.5" exhaust, short real cold air ram, aftermarket chip, custom o2 housing, port matching for vj11 with o2 housing, 17 lbs of boost. If I throw the same turbonetics t3 50 (I would use the 60 for the Mx6/Probe) I could easily make 300 horsepower with same support mods + if I was doing it cheap an aftermarket rising rate fuel regulator something higher than 1:1.




 

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Nice work.
Remember A/R is just a fraction like trim. Area / Radius does of course play a role in spool up but the larger the exhaust wheel is the smaller the A/R needs to be to maintain RPM. And just like trim between tip and base of thurbine wheel you can get the same trim number representing diferent non linear sizes, Turbine A/R can be the same, but all the geometry can be different based on the shape of the snail housing (how close or far the area is from the radius center point. With T-series turbos the A/R will absolutely designate an RPM range (that varies with each engine) with the VJ11 it's a WTF number, most other turbo's with the same flow rating with a .48 A/R turbine housing will spool slower on the F2T. So if your only getting boost at 5000rpm on the VJ11 you might want to go smaller than .48 a/r on the stage 1 t3 turbine.
 

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Nice work.
Remember A/R is just a fraction like trim. Area / Radius does of course play a role in spool up but the larger the exhaust wheel is the smaller the A/R needs to be to maintain RPM. And just like trim between tip and base of thurbine wheel you can get the same trim number representing diferent non linear sizes, Turbine A/R can be the same, but all the geometry can be different based on the shape of the snail housing (how close or far the area is from the radius center point. With T-series turbos the A/R will absolutely designate an RPM range (that varies with each engine) with the VJ11 it's a WTF number, most other turbo's with the same flow rating with a .48 A/R turbine housing will spool slower on the F2T. So if your only getting boost at 5000rpm on the VJ11 you might want to go smaller than .48 a/r on the stage 1 t3 turbine.
I'm not just boosting at 5000 rpms. I have initial boost start to kick in about 2000 rpms. 1st gear it only is about six psi by the time I normally shift, but does hit full boost at about 7000 rpms (15 lbs) which is super quick to red line where I had to get use to immediately shifting to 2nd. 2nd gear it is about 8 psi by the time I normally shift it does hit full boost by about 6500 rpms. 3rd gear it is about 10 psi I normally shift but does hit full boost by about 6000 rpms. It is hard to say if it is boost lag or if it is hitting the surge line or something else. The compressor map for the vj11 when I plot my numbers with the engines cfm out put and rpm band looks great. However first through 3rd I hit fast and it doesn't like the high rpms in those gears. 4th feels just about right with a little bit of the same things when Im high up. 5th feels great from where ever I drop it in all the way to red line. I almost thinking it is the chipped ECU. It is not knock. I'm in the middle of soldering up MS2. I'll switch to MS2 before I switch turbos. I'll rule out the ECU. I'll make sure the compressor map matches before buying the turbo. A Garett T3 50 fits just fine (a little bit on the large side), but I'm never seen the actual map for the Turbonetics. With the improvements to the turbine and compressor wheel over the last twenty years with the ceramic ball bearings I'm not worried. Their 54 mm turbine they have it paired all the way down to a one litre engine with a similar compressor wheel.
 

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Right now it has a lot of lag, but jumps like a rocket from 5000 rpms...
Choose a set-up that makes it jumps like a rocket 1500 to 2000 rpm earlier and hold it to redline.
Full boost at 7000rpm wtf is redline.
What does it matter when you hit full boost if your shifting before that. If you can double the duration peak torque in the usable rpm band it has the same results as doubling peak torque on the same torque curve.

I have not experienced this issue, once I started porting the heads on the f2t and running proper boost control I made the same boost in every gear with 0 lag creep on any turbo, instant full boost wherever I floor it to redline in any gear. Turbine housing back pressure can cause these symptoms but in reverse, back pressure choke and lower boost in higher gears.

You should consult turbo manufactures with your rpm to boost and gear results and see what their opinion is.
Are you running a VJ11 wastegate actuator, is boost control set up as I pictured above, did you port the wastegate hole larger? More exhaust bypass at less travel makes the waste gate more accurate and controllable.
 

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Sorry OP about littering the thread. I figured out my problem. I tried turning the boost controller up a little bit. I was having such a boost lag down low, but it wasn’t really making sense because what it was doing was just weird. I had the boost controller all the way off because I could not get it to hold at 9 psi which is what the spring should be. What I wasn’t realizing is that with the boost controller all the way off it must have been causing havoc on the function of the wastegate actually staying closed (it makes sense that all the pressure being built in the system was probably slamming the wastegate open and it took the high cfms of high rpms to spin the turbo). Before I had minimal boost 1st through 3rd until high rpms and 4th & 5th felt about normal. A few clicks of the boost controller stabilized the wastegate and now I have boost way earlier in every gear. Holy cow I was happy. It wasn’t boost lag it was the crappy wastegate that is thirty years old. Another reason to switch to something newer. The boost creep now that I’m thinking about it from a different angle is caused by the wastegate itself being in the way of the divorced wastegate tube; it has to go around it to make it into the divorced wastegate tube. Last time I had it apart I shaved the dividing wall down a little and it lowered the boost creep. Now that I turned the boost controller up (on) it didn’t just spike the boost and was holding about 10 psi. I will have to play around with where I want it set. I’m sure if I lay into the higher rpms which what I had to do get boost in 1st through 3rd before it will creep, but I don’t have to lay into to get boost in those gears anymore. It was like a hot knife slicing through butter. Very satisfying after all the work for it to work like it should.
 

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Discussion Starter · #17 ·
no worries, good stuff here. still trying to absorb everything MC had posted above. dropped the car off at the tuner last Monday and hoping to have her back some time next week. will post new dyno grahs with the t-bird turbo.
i've actually never had any boost spikes on the vj-11 with my ball/spring mbc.
 

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Sorry OP about littering the thread. I figured out my problem. I tried turning the boost controller up a little bit. I was having such a boost lag down low, but it wasn’t really making sense because what it was doing was just weird. I had the boost controller all the way off because I could not get it to hold at 9 psi which is what the spring should be. What I wasn’t realizing is that with the boost controller all the way off it must have been causing havoc on the function of the wastegate actually staying closed (it makes sense that all the pressure being built in the system was probably slamming the wastegate open and it took the high cfms of high rpms to spin the turbo). Before I had minimal boost 1st through 3rd until high rpms and 4th & 5th felt about normal. A few clicks of the boost controller stabilized the wastegate and now I have boost way earlier in every gear. Holy cow I was happy. It wasn’t boost lag it was the crappy wastegate that is thirty years old. Another reason to switch to something newer. The boost creep now that I’m thinking about it from a different angle is caused by the wastegate itself being in the way of the divorced wastegate tube; it has to go around it to make it into the divorced wastegate tube. Last time I had it apart I shaved the dividing wall down a little and it lowered the boost creep. Now that I turned the boost controller up (on) it didn’t just spike the boost and was holding about 10 psi. I will have to play around with where I want it set. I’m sure if I lay into the higher rpms which what I had to do get boost in 1st through 3rd before it will creep, but I don’t have to lay into to get boost in those gears anymore. It was like a hot knife slicing through butter. Very satisfying after all the work for it to work like it should.
I don't think your littering the tread, this post shows the importance of proper or better functioning set up.

Your original Boost/gear/RPM results didn't sound right, this sounds better but I am not sure you have rationalized this properly. The VJ-11 actuator is rated 7 -7.5 psi.
Having the wastegate flap shut is the fastest way to build boost, all the exhaust pressure goes through the turbo making it spool faster.
If the wastegate flap was blocking exhaust flow through the divorced tube it would result in boost spikes not boost lag.
If the wastegate isn't flowing exhaust the only thing limiting boost is the flow of the exhaust system.

All the facts where adding up to the VJ-11 being to big for the 1.3L but that didn't make sense.
Did you have any issues running the same size divorce wastegate pipe on the F2T as the 1.3L?
If not than it's not the flap blocking waste gate flow.

Now that I think about it I experience the exact same boost characteristics you where.

The first T3 I installed (saab 9000) had a 2.5" diameter wastegate and there was no way to fit it between the compressor and block, I cut the bracket bracket up and lightly tack welded a Vj-11 actuator and piece of its bracket, I didn't want to damage the actuator. Because the Mazda actuator operates at such low boost I added throttle body springs between the actuator body and swing arm to increase the wastegate actuator spring resistance. A few months later while starting to race my friends audi a4 right after I told him my car is much faster than his, the tack welds snapped, the wastegate flap stayed opened and my car boosted exactly like yours. He said my cars isn't much faster, we drove to my shop, I saw the problem right away, pried the actuator into place, welded it properly and left his audi in the dust.

It almost sounds like your actuator is shot, does it still have resistance? Can you move it by hand?

It's fairly easy to change actuators even on the VJ-11 setup.
Get an adjustable wastegate similar to this:

13522


Cut the VJ-11 actuator off its bracket, modify, weld to, cut up and rebuild the factory bracket to fit and drill the 3 holes for the new wastegate. Cut the end loop off the new wastegate and weld the end of the VJ11 actuator to it, shorten the threaded rod if necessary. I recommend using one you can spin the actuator rod on, this war you can adjust the actuator tension by loosening the lock nut and spinning the rod instead of having to undo the swing valve and spin the end.


no worries, good stuff here. still trying to absorb everything MC had posted above. dropped the car off at the tuner last Monday and hoping to have her back some time next week. will post new dyno grahs with the t-bird turbo.
i've actually never had any boost spikes on the vj-11 with my ball/spring mbc.
I must apologize. My statement should say, ball and spring boost controllers do cause boost spikes on the F2T because:
The sudden torque band of the long stroke low revving F2 engine and relatively small size of the VJ-11 results in instant boost.
Ball and spring boost controllers hold off boost pressure going to the wastegate until it overcomes the spring, by the time it overcomes the spring and makes the wastegate actuator move the turbo already boosted higher (spike).
Now my reasoning is this if :Forge sport bypass/bov works on eagle talons, toyota mr2's and other turbo cars, but the high engine vacuum of the F2T holds these valves open at idle, causing the car to stall or spool slow. Many brands of BOV's also leak at idle and under boost with the spring fully tightened on the F2T and require shims to stiffen the spring to stop this leaking.
Although these may work on many vehicles the ones that actually work on the F2T are better designed and work better on the other vehicles as well. And I advise everyone to steer away from them.

Example:
A Blow off valve that's vent port flap is held shut by boost pressure like an HKS (Type B) works the exact opposite of a cup and spring BOV (Type A). The cup on type A bov's has boost pressure trying to push it opened while the spring and boost pressure from the vacuum line try to hold it shut, the more boost the engine makes the more boost pressure on the large surface of the cup overcomes the resistance of the spring and small vacuum line and the BOV leaks under boost. HKS type bov open against boost, the higher the engine boost is, the harder the valve is pushed shut.
Type A - The more you boost the more it wants to leak.
Type B- The more you boost the tighter it seals.

Based on these facts to anyone looking for a BOV for any forced induction application I recommend type B blow off valves.

When I started writing this I though maybe I am wrong because you aren't getting boost pikes with your Turbosmart style boost controller, but really I just mentioned one problem with this type of boost controller and moved on to explaining a set-up that works better on all turbo cars.
Ball and spring style boost controllers like this :
13523


Suck at properly activating the wastegate, bleeding off the correct amount of air, maintaining steady boost through the power band and delivering consistent boost through the gears.

The bleed off style boost control set up I made a diagram of simply and consistently bleeds off an amount of the pressure going to the wastegate. The wastegate will always operate at it's pressure rating say 7.5psi, simply bleed of the extra boost you want to see. Want 15psi, bleed off 7.5psi, why this works better is because instead of resisting the flow of pressure you allow it to take the path of least resistance, so because the bleed valve is set to allow 7.5psi of air passed it with the resistance the waste gate actuator only has pressure applied to it above 7.5psi.
On a 7.5psi wastegate when boosting 9psi with this boost control set up set at 15psi. The waste gate actuator is only getting 1.5psi applied to it. This set up will be consistent in every gear because both hose sizes (waste gate actuator and boost controller) the boost controller will always bleed off 7.5 psi no matter the pressure behind it and the wastegate will always open at 7.5 psi controlling the pressure on it.
The only thing left to effect wastegate travel is exhaust pressure on the waste gate flap at higher boost than the wastegate actuator rating tends to push it opened more alowing boost to fall at higher rpm. The actuator has 7.5psi pushing on it but the flap has 15psi worth of exhaust pushing against it. Porting the wastegate hole is the only way to reduce the effect off exhaust pressure on the flap.

Once the boost control set-up I recommend and the wastegate hole ported, With whatever it is your working with you have given your set-up the best chance of performing the way you expect. The rest is bassed on the wastegate actuator design, flap size, exhaust flow, turbo choice and engine flow. An adjustable wastegate actuator allows you to move the wastegate diaphragm tension closer to the exhaust pressure on the flap.
The VJ-11 actuator or flap design sucks at handling 2time the exhaust pressure the actuator sees. The Saab T3 flap and whatever adjustable wastegates I have been running do a great job keeping the wastegate flap steady, I started with the actuator adjusted to 8 psi and ran 22psi with the manual boost controller, than adjusted the actuator to 15psi and ran 30psi with boost control.

So like I said the first step in making the most/steady power from the set-up you have is proper boost control.

If you open your boost controller more do you get more than 10+ psi in 2nd gear? If so it's boost control related, if not it could be restrictive exhaust flow, maybe the VJ-11 is big enough for Solerpwr's 1.3L to have gear related beak boost limits (probably not) but even a 1.6L 323 can manage 18psi on a VJ-11 in all 5 gears. There is no reason you shouldn't be seeing 15 psi in 1st and 2nd gear on a 2.0L 16valve engine with a VJ-11.

Disconnect the wastegate hose, cap the compressor fitting and slowly accelerate in second while watching the boost gauge If you see 15psi that ball and spring boost controller is the cause of different boost in every gear, if you can't boost more than 10+ psi your exhaust could be too restrictive but that should limit boost to the same psi in every gear.

Both your and Solerpwr's builds boost psi to gear changes on a VJ-11 have me puzzled but more so your 2.0L build.
 

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I don't think your littering the tread, this post shows the importance of proper or better functioning set up.

Your original Boost/gear/RPM results didn't sound right, this sounds better but I am not sure you have rationalized this properly. The VJ-11 actuator is rated 7 -7.5 psi.
Having the wastegate flap shut is the fastest way to build boost, all the exhaust pressure goes through the turbo making it spool faster.
If the wastegate flap was blocking exhaust flow through the divorced tube it would result in boost spikes not boost lag.
If the wastegate isn't flowing exhaust the only thing limiting boost is the flow of the exhaust system.

All the facts where adding up to the VJ-11 being to big for the 1.3L but that didn't make sense.
Did you have any issues running the same size divorce wastegate pipe on the F2T as the 1.3L?
If not than it's not the flap blocking waste gate flow.

Now that I think about it I experience the exact same boost characteristics you where.

The first T3 I installed (saab 9000) had a 2.5" diameter wastegate and there was no way to fit it between the compressor and block, I cut the bracket bracket up and lightly tack welded a Vj-11 actuator and piece of its bracket, I didn't want to damage the actuator. Because the Mazda actuator operates at such low boost I added throttle body springs between the actuator body and swing arm to increase the wastegate actuator spring resistance. A few months later while starting to race my friends audi a4 right after I told him my car is much faster than his, the tack welds snapped, the wastegate flap stayed opened and my car boosted exactly like yours. He said my cars isn't much faster, we drove to my shop, I saw the problem right away, pried the actuator into place, welded it properly and left his audi in the dust.

It almost sounds like your actuator is shot, does it still have resistance? Can you move it by hand?

It's fairly easy to change actuators even on the VJ-11 setup.
Get an adjustable wastegate similar to this:

View attachment 13522

Cut the VJ-11 actuator off its bracket, modify, weld to, cut up and rebuild the factory bracket to fit and drill the 3 holes for the new wastegate. Cut the end loop off the new wastegate and weld the end of the VJ11 actuator to it, shorten the threaded rod if necessary. I recommend using one you can spin the actuator rod on, this war you can adjust the actuator tension by loosening the lock nut and spinning the rod instead of having to undo the swing valve and spin the end.




I must apologize. My statement should say, ball and spring boost controllers do cause boost spikes on the F2T because:
The sudden torque band of the long stroke low revving F2 engine and relatively small size of the VJ-11 results in instant boost.
Ball and spring boost controllers hold off boost pressure going to the wastegate until it overcomes the spring, by the time it overcomes the spring and makes the wastegate actuator move the turbo already boosted higher (spike).
Now my reasoning is this if :Forge sport bypass/bov works on eagle talons, toyota mr2's and other turbo cars, but the high engine vacuum of the F2T holds these valves open at idle, causing the car to stall or spool slow. Many brands of BOV's also leak at idle and under boost with the spring fully tightened on the F2T and require shims to stiffen the spring to stop this leaking.
Although these may work on many vehicles the ones that actually work on the F2T are better designed and work better on the other vehicles as well. And I advise everyone to steer away from them.

Example:
A Blow off valve that's vent port flap is held shut by boost pressure like an HKS (Type B) works the exact opposite of a cup and spring BOV (Type A). The cup on type A bov's has boost pressure trying to push it opened while the spring and boost pressure from the vacuum line try to hold it shut, the more boost the engine makes the more boost pressure on the large surface of the cup overcomes the resistance of the spring and small vacuum line and the BOV leaks under boost. HKS type bov open against boost, the higher the engine boost is, the harder the valve is pushed shut.
Type A - The more you boost the more it wants to leak.
Type B- The more you boost the tighter it seals.

Based on these facts to anyone looking for a BOV for any forced induction application I recommend type B blow off valves.

When I started writing this I though maybe I am wrong because you aren't getting boost pikes with your Turbosmart style boost controller, but really I just mentioned one problem with this type of boost controller and moved on to explaining a set-up that works better on all turbo cars.
Ball and spring style boost controllers like this :
View attachment 13523

Suck at properly activating the wastegate, bleeding off the correct amount of air, maintaining steady boost through the power band and delivering consistent boost through the gears.

The bleed off style boost control set up I made a diagram of simply and consistently bleeds off an amount of the pressure going to the wastegate. The wastegate will always operate at it's pressure rating say 7.5psi, simply bleed of the extra boost you want to see. Want 15psi, bleed off 7.5psi, why this works better is because instead of resisting the flow of pressure you allow it to take the path of least resistance, so because the bleed valve is set to allow 7.5psi of air passed it with the resistance the waste gate actuator only has pressure applied to it above 7.5psi.
On a 7.5psi wastegate when boosting 9psi with this boost control set up set at 15psi. The waste gate actuator is only getting 1.5psi applied to it. This set up will be consistent in every gear because both hose sizes (waste gate actuator and boost controller) the boost controller will always bleed off 7.5 psi no matter the pressure behind it and the wastegate will always open at 7.5 psi controlling the pressure on it.
The only thing left to effect wastegate travel is exhaust pressure on the waste gate flap at higher boost than the wastegate actuator rating tends to push it opened more alowing boost to fall at higher rpm. The actuator has 7.5psi pushing on it but the flap has 15psi worth of exhaust pushing against it. Porting the wastegate hole is the only way to reduce the effect off exhaust pressure on the flap.

Once the boost control set-up I recommend and the wastegate hole ported, With whatever it is your working with you have given your set-up the best chance of performing the way you expect. The rest is bassed on the wastegate actuator design, flap size, exhaust flow, turbo choice and engine flow. An adjustable wastegate actuator allows you to move the wastegate diaphragm tension closer to the exhaust pressure on the flap.
The VJ-11 actuator or flap design sucks at handling 2time the exhaust pressure the actuator sees. The Saab T3 flap and whatever adjustable wastegates I have been running do a great job keeping the wastegate flap steady, I started with the actuator adjusted to 8 psi and ran 22psi with the manual boost controller, than adjusted the actuator to 15psi and ran 30psi with boost control.

So like I said the first step in making the most/steady power from the set-up you have is proper boost control.

If you open your boost controller more do you get more than 10+ psi in 2nd gear? If so it's boost control related, if not it could be restrictive exhaust flow, maybe the VJ-11 is big enough for Solerpwr's 1.3L to have gear related beak boost limits (probably not) but even a 1.6L 323 can manage 18psi on a VJ-11 in all 5 gears. There is no reason you shouldn't be seeing 15 psi in 1st and 2nd gear on a 2.0L 16valve engine with a VJ-11.

Disconnect the wastegate hose, cap the compressor fitting and slowly accelerate in second while watching the boost gauge If you see 15psi that ball and spring boost controller is the cause of different boost in every gear, if you can't boost more than 10+ psi your exhaust could be too restrictive but that should limit boost to the same psi in every gear.

Both your and Solerpwr's builds boost psi to gear changes on a VJ-11 have me puzzled but more so your 2.0L build.
The o2 housing is not stock. It does indeed put the wastegate in between the divorced wastegate tube and the wastegate hole. If the main chamber is blocked off then regardless of widening the wastegate hole boost will creep up (not spike). The solution is shortening the dividing wall to the main chamber letting some of the wastegate exhaust out there and some will still flow out the divorced wastegate tube. When I said wastegate earlier I was also including the actuator. However, it is not frozen and does open and close by hand. The actuator with the boost controller off which means it is letting all the pressure through (no blead off) has to be opening the wastegate early. Now that I turned the Turbosmart boost controller a few clicks + the actuator is not just slamming open the wastegate. The actuator is either not holding because it is weakened (it felt like it was at least 7.5lbs spring), or the pressure coming off the turbo nipple is higher then the intended pressure of the actuator, or the engine exhaust pressure is higher or adding to the wastegate opening early. The picture below is before I welded the dividing wall between the main exhaust chamber and the divorced chamber. Either way letting some of the pressure bleed off from turning on the Turbosmart boost controller moved it beyond the pressure threshold and now it is staying closed.






This is even a brand new CHRA for the VJ11. It was dirt cheap.


When the wastegate is open the exhaust pressure through the wastegate hole has to move around the wastegate itself and then flow into the divorced tube if the wall in between the two is fully sealed or even mostly sealed.
 

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Did you have any issues running the same size divorce wastegate pipe on the F2T as the 1.3L?
If not than it's not the flap blocking waste gate flow.
Your probe GT set-up:
Your 1.3L set-up
The o2 housing is not stock. It does indeed put the wastegate in between the divorced wastegate tube and the wastegate hole. If the main chamber is blocked off then regardless of widening the wastegate hole boost will creep up (not spike). The solution is shortening the dividing wall to the main chamber letting some of the wastegate exhaust out there and some will still flow out the divorced wastegate tube. When I said wastegate earlier I was also including the actuator. However, it is not frozen and does open and close by hand. The actuator with the boost controller off which means it is letting all the pressure through (no blead off) has to be opening the wastegate early. Now that I turned the Turbosmart boost controller a few clicks + the actuator is not just slamming open the wastegate. The actuator is either not holding because it is weakened (it felt like it was at least 7.5lbs spring), or the pressure coming off the turbo nipple is higher then the intended pressure of the actuator, or the engine exhaust pressure is higher or adding to the wastegate opening early. The picture below is before I welded the dividing wall between the main exhaust chamber and the divorced chamber. Either way letting some of the pressure bleed off from turning on the Turbosmart boost controller moved it beyond the pressure threshold and now it is staying closed.
Of course the actuator is not frozen but the fact you can "move it opened and closed by hand" is concerning, I recall having to grip the wastegate rod and pull really hard to get even the VJ11 wastegates to open and they snap shut like a snapping turtle. I recall being surprised at how much resistance the VJ11 waste gate has, pulled the turbo/manifold/o2 housing off in one piece, picket the hole assembly up by the actuator rod (actuator toward the floor) expecting the assembly's weight to open the waste gate but I had to shake it to get it to opened, this wastegate wasn't seized or stiff and would hold 7-8psi with boost control off.
I always put a 12 or 13mm box wrench on the wastegate flap tab to test them, I move the wrench until the wastegate flap is opened, should feel like 15 to 20 lb torque is required to move the wrench completely to opened.
Remember the waste gate actuator should start to move at 7.5 psi and it takes a lot more pressure for it to be fully opened.

Sounds like your wastegate actuator is shot, it should build 7.5psi just as fast with or without the boost controller.


Turbosmart style boost controllers suck at properly activating the wastegate, bleeding off the correct amount of air, maintaining steady boost through the power band and delivering consistent boost through the gears.

So like I said the first step in making the most/steady power from the set-up you have is proper boost control.


With very little knoledge and experience the first boost controller I bought for my first F2T was a turbosmart. I followed the instruction, installed it close to the wastegate under the hood, secured it as away from heat as I could get it. Drove the car and spooled in 3rd or 4th, pulled over and raised the boost over and over until I saw 15psi peak boost on the boost gauge. Drove It for a few days without issues. Took it to the track and when flooring it from first gear on was getting 13psi, so I turned it up between runs until I got 15psi, ran 25 or 30 runs down the track without issues. On the way home I spooled in 4th gear on the highway. Instant boost spike and BOOM:

13524


In my ignorance I thought this was just the way the F2T behaves with boost control and I kept running the turbosmart boost controller, every time I went to the track I would have to turn the boost up. On the way home I would have to play with the gas pedal to limit boost to 15psi (it was always late and no good places to pull over), The next day I would have to go and readjust the boost on the highway until 15psi was the maximum. Over the two years I stubbornly ran that turbosmart boost controller I probably pulled over, popped the hood and adjusted that stupid boost controller 3000 or 4000 times, cold nights boost was to high, warm days boost was too low...

Then one day I saw a small orange box sitting on my shop partners tool box, it was labelled forge motorsports I opened it to find one of these:


I played with it for a minute blowing in the spouts to figure out how it works. Decided if I blocked off the bottom port I could use it as a bleed off valve boost controller and install it in the dash, I told my shop partner he should by himself one and I installed it in my car and threw the Turbosmart in a drawer. Now I could adjust the boost from the drivers seat and didn't have to pull over 4 times a day looking like I was having car troubles.
I set it to 15psi. I noticed the care came on boost smoother, I wasn't getting boost spikes when flooring the car in low rpm 4th gear like before, it was holding higher boost to redline.
That night as it started to cool down I was so happy I wouldn't have to pull over to lower boost and could do it from the drivers seat but I didn't have to the car was still boosting 15psi. It was very ironic now that I had boost control at my finger tips I never had to touch it. No longer gad to adjust boost ate the track either.

My boost control set up was still flawed I was taking pressure from the compressor housing to activate the waste gate, I Teed the boost controller at the wastegate and didn't run any inline reducers, I tried the set up with and without the factory reducer after the T before the wastegate and saw no changes so I ran without it. I never tried it before the T.

Installed a TIAL external waste gate on my 89GT, followed the directions for boost control set-up, due to the work I had been doing on industrial building pneumatic systems I understood why TIAL takes waste gate signals from the charge pipe instead of the Turbo, reducing the variables increases consistency, I also understand why manufacturers use the compressor housing signal to control the wastegate If there is a boost leak the wastegate could still get some boost signal from the compressor housing. I also knew that putting a reducer before the wastegate hose T would increase the sensitivity of the boost controller and wastegate.
I implemented this boost control set-up an all the internal wastegate set-up, boost was holding to redline on VJ-11 turbos.
Had a box of HVAC pressure control valves I pulled out of buildings when converting them to electric systems. They look and operate like the forge motorsport but has two spouts not 3. I installed these on all customers and friends cars. In many cases I would disconnect their boost control set-up and temporarily install one of this set-ups and sent them to drive their cars, they would come back and have me permanently install the new set-up and remove the old boost control.
I would ask them if they wanted to keep the old system, they said no.

Over the years many types of ball and spring boost controllers have joined the Turbosmart, a few are turbosmarts some are knock offs, some a designed differently but function the same, the worst was an expensive plastic kit, the boost controller looks like a compressor regulator valve, it's huge, It comes with pale blue vacuum hose, if you fold the hose over itself it breaks. The instruction are to run one hose from the compressor fitting to the in dash boost control in port and run the out port back to the wastegate using the supplied crappy blue hose. The giant valve has a ball and spring and bleed off set up just like the Turbosmart, and seeps turbo boost into the cabin, it seeps from under the giant black control knob. The first time I saw this kit on a kids car I though he made it, he was spiking 16psi at spool up and holding 12psi, so in the time it took for the ball to move and pressure to get back to the wastegate the turbo would build 4 psi over set boost, even better was that all the pressure in the wastegate line vented back through the control knob every time the wastegate closes.
If the cheap blue hose breaks the wastegate stays closed, with a little turbo it blows the turbo with a big turbo it blows the engine. This kit is also in the drawer.

I use high pressure 1/4 inch fuel line and stainless steel fuel line clamps, the kind with the solid metal sleeve and nut and bolt, as wastegate system hose, it's high pressure rated, durable and holds up to oil. Always use strong hose over pretty hose.

What can't be bought but often comes at great cost: Experience.
What is free to acquire but priceless when you need it: Knowledge.

This is all from experience many years of it, much trial, some error.

Your build is yours. But if you came to the my shop to visit one of the other shop owners and I saw that turbosmart boost controller you would be leaving with a different boost control system on the car.

Do yourself a favor pressure test the wastegate and get rid of the turbosmart boost controller.

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What to do with the compressor housing fitting?

FAILSAFE.

A boost leak in the system with any type of boost control will tax the turbo or kill it. The same with running too much boost through the engine.
A gauge overboost warning light helps protect the engine.
The Overboost warning system I just came up with thanks to 99BLKZX2 and Solerpwr is better.


This requires a Normally Opened adjustable pressure switch, some good hose, two clamps, some wire, 1LED bulb and resistor. And most importantly a car with no boost leaks.
Connect and clamp one end of the hose to the compressor housing wastegate port and the other to the pressure switch.
run a wire from a body ground to one side of the switch and from the other side of the switch to the ground side of the LED bulb, connect the positive side of the led bulb to a switched 12V source.
If you have an air compressor and pressure regulator you can find the adjustment point on the pressure switch for 12psi, take the adjuster lock nut off pressure switch, take a permanent marker and put a mark on the threads of the adjuster and on the pressure which now find 14psi on the switch and make are 2nd mark on the threads at the first mark you made on the switch. That is the adjustment degree for "2 PSI", (without a compressor you can do this by boosting 12psi than 14psi with the pressure switch connected to the turbo housing).
With the pressure switch connected to the turbo housing find the adjustment point on the switch where the light just comes on at the maximum boost you want to run and add "2 PSI"

Now you have an overboost warning light. Yes you can get them built into boost gauges but that doesn't protect the turbo or identify boost system leaks.

-But what about the engine? An overboost gauge warning light protects the engine by monitoring maximum manifold pressure and warning the driver when it gets to high. How would an overboost warning light at the compressor housing do that?
You can't have more manifold pressure unless the turbo compressor makes more pressure, by having the warning light run off the compressor boost you get a warning that extra boost is coming, a gauge overboost light only lets you know that it's here. Also the compressor overboost warning light will alert the driver of any boost system leaks or other issues that would cause the turbo to have to generated more boost to maintain set manifold boost.

Overboost warning system 2.0. with boost cut:
Add a Normally opened solenoid valve to the hose going to the boost controller, connect the positive side of the solenoid valve to a switched 12V source connect the ground side to the pressure switch out signal.
Anytime the pressure switch detects overboost the solenoid valve will shut off the boost controller hose and boost will drop to wastegate actuator only. Faster than one could react to the warning light.
This normally opened solenoid could also be operated using a toggle switch giving the set up 2 stages of boost, stage 1 wastegate, stage 2 boost controller.

More stages of boost can be added to the boost control system by adding a T between the normaly opened solenoid valve and manual boost controller, run a normally closed solenoid valve of the T and another bleed adjuster set to X psi. So when a toggle is activated the closed solenoid opens and you run X PSI more than stage 2.
 
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