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Discussion Starter · #61 ·
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I've uploaded just the photo showing the positioning of the cylinders before I put the head on, hopefully it works and hopefully it's correct.

I understand what you're saying about finding an F2T car to use, the problem with that is that a) they're very rare over here and b) I want to keep the current 626 because it's a station wagon and turbo wagons are cool (and useful) (and we didn't get any factory turbo wagons over here).

Let me ask, if you were in my position, which of options 1, 2 or 3 would you do?

For option 1... you're saying I can use the F2T intake manifold as long as I use the NA injectors?
I don't really understand what you're saying about the injector emulator, extra injector, boost controller etc, but I'm happy to do more research.
Question though. If I understand correctly the extra injector is necessary because the NA injectors can't supply enough fuel with say 7.5psi of boost.
The F2T injectors can, so I can't use them why? Is the plug different? Or the impedance? Surely it's easier and more effective to find a way to use the F2T injectors even if it involves adding a resistor or something?
 

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The block is non interference, you don't need the crank and cam in position before assembling it, just put the head on and turn the crank and head until the marks line up, put on the belt.

I did not say find an F2T car to use I said keep an eye out for a cheap F2T parts car, you get the GT transmission, axles mounts, shifter assembly, coil, igniter, ecu, harnesses, firewall solenoids... for 200-300$ instead of buying the F2T ecu and maybe a coil for the same price. In the mean time you get the car running reliably, efficiently and affordably @ 0.5Bar.

Station wagon are cool? Well they did lead to the MiniVan.

You can use the F2T intake manifold but you want to use the N/A throttle body, vacuum rail, firewall vacuum sensors and injectors, other wise the manifolds are the same, it's just a different sticker on the top. Basically you are adding a turbo with oil and coolant supply, an oil cooler and lower compression pistons to your N/A tuned car. Limit timing, give it enough fuel and enjoy.

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Injectors:
Once on my 88mx6 F2T I was running the highly ported "test head", any time I would slow spool in fourth the factory turbo would explode, I made a block off plate, pulled the turbo out of the turbine housing and bolted on the plate, looped the oil and coolant going to the turbo, ran the n/a accordion and drove the car N/A for a while, it was pig rich above 3000rpm. I through in some n/a injectors but the car wouldn't start or idle because the F2T injectors deliver 55% the ECU duty cycle would be 55% lower to deliver the same amount of fuel at idle and cruise as the N/A.

That means if you put the GT injectors on an N/A ECU they will deliver 55% more fuel than the N/A ecu is calling for. The N/A tune ECU is not mapped out like the GT ECU, at whatever point the N/A ECU would put the N/A injectors at 100% duty cycle the GT injectors will be at 100% duty cycle, pretty sure the N/A ECU won't wait for the airflow required for 15psi manifold pressure to pass through the air flow meter to put the injectors at 100% duty cycle.
If the car ran of a map sensor your could increase it's range say from a 1 bar (0-5V from vac to atmosphere) sensor to a 2bar sensor (0-5V from vac to 1bar above atmosphere) and double the size of the injectors, this would cut the ECU's "resolution" in half (0-2.5V for each 1bar of pressure).
The F2 uses an air flow meter, you can't easily increase it's size and cut it's "resolution" to run bigger injectors but you can tighten the spring in the AFM making it consume more volume of air at less flap travel at higher vacuum to reduce the amount of fuel the injectors deliver and cut the air flow meters resolution. But at idle and up to 3000rpm the ECU is in closed loop and uses the o2 sensor to regulate fuel and 55% more injector is beyond the ECU's map correction capacity.

Lets take my GT's for example I don't throw in 450cc injectors on the factory chipped GT ECU and try to tune idle and cruise A/F's and run rich all the time... I run the factory injectors off the ECU, because I need more fuel than the factory pump can deliver I run a bigger pump and need an adjustable fuel pressure regulator to bring fuel rail pressure back down to factory so the car doesn't idle or run rich. All extra fuel required to go from 15psi to 30psi comes from a simple digital system extra injector controller and two 650cc batch fired injectors (so they can deliver up to 1300cc/min to the engine).
Because I can't control timing I use water/meth injection above 21psi to prevent pre ignition and make more power than it would pulling timing at 30psi.

So what is easier and more effective:
1 using a boost vacuum signal to run a pressure switch or extra injector controller do deliver all fuel needed for boost (pressure above 1 bar atmosphere) and have the same idle and drive-ability and fuel millage it did N/A when off boost.
2 fooling the ECU into running somewhat okay air/fuel ratio's across the map with 55% larger injectors and no way to remap the ECU duty cycle output.

It's funny the fact the F2T exists is what's limiting you.
If there was no F2T and you wanted to turbo your car you would google how to do it and see you need to install a turbo (no shit), pull peak timing and give it more fuel under boost. You would figure out the easiest way of doing each of those things.
Because the F2T exists you are trying to figure out how to make an F2 an F2T : Buy a donor car and use all the F2T harnesses and parts needed under the hood. Or buy a bunch of F2T pieces one at a time and trouble shoot, splice, guess, research, loose sleep... Stand alone would be easier and you can run any size injector in the manifold you want and have more control / are further ahead than splicing the car to GT ECU.

You can make as much power on the N/A set up with an extra injector controller as having the F2T ecu and wiring and a chip, coil, igniter, fire wall sensors, injectors... on both set ups the IHI VJ11 is the limiting factor (amount of boost before the turbo blows up).
For me the engines run GT everything, when I upgrade the turbo and everything else and need more fuel I need an extra injector controller, because it's a GT the ECU and it's injectors cover the first 15psi boost and I control extra fuel above that to 30psi. I work with what I got for factory ECU.
For you on the N/A set up adding boost and extra injectors means you control fuel above 0psi, if you run the same turbo upgrade and other mods I do on your 7.8:1 compression block your extra injector controller would control fuel from 0-30 psi and you would just need bigger injectors in your injector controller bungs.
The only tuning difference is mechanical timing is much easier to limit than electronic timing is to control.
Mechanical differences, the gt transmission and axles are stronger and the rad is bigger.

Hmm, I would want to run the GT transmission more than the GT ecu, what would be the easiest and cheapest way to get all the parts necessary to convert the transmission? net dust shield, starter plate, clutch, flywheel, mounting bolts, clutch slave, all 3 mounts and some of the bolts, the axles and half shaft, the spindles, the gear change rod rod assembly. What would be the easiest and cheapest way to get all those parts? Oh I know a parts car with blown motor that's sold cheap. Hey that would probably have GT wire harnesses, ecu and sensors.

An extra injector controller or pressure switch/injector emulator can still be used if you ever do find a gt ecu and harness and convert it, if you upgrade the turbo, I highly recommend a garrett T3 45trim from a saab 9000 88-89, at the same boost it's no faster that the VJ-11 but the power band is better, much easier on the transmission and breaths better at redline. The T3 will handle the same 30 PSI the 60 trim will (same shaft and exhaust wheel/housing), the garrett's generate a lot less hot air than the VJ-11, which is easier on the engine, oil, cooling system...
All you do is set the injector controller to come on at 15psi instead of 0, add boost and adjust the injector gain until desired A/F is achieved on the wideband gauge. (Tune fuel according to boost).
With a pressure switch/emulator set up move the pressure switch setting from 2 psi to 15psi. Watch the A/F and turn up the boost until the desired A/F is achieved. (Adjust boost according to fuel).

F2T target air fuel ratio at full boost 11.8 A/F (low rpm full boost) getting richer to 11.3 A/F (high rpm full boost).
 

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Discussion Starter · #63 ·
Alright I think I understand what you're saying about why I can't use the F2T injectors.
I think I need to do some more research to make sure I understand how the extra injector will work etc.

Questions.
1. A potential problem I can see is that it sounds to me like when the extra injector kicks in, it'll be supplying the same amount of extra fuel regardless of what load the engine is under, what the boost pressure is, etc - whereas a factory turbo car would of course be constantly adjusting the fuelling as required, so it's possible that the engine will be running lean or rich under various levels of boost...?
2. If I do use this option (or any option retaining the NA ECU and harness) will I have to swap over to use some of the NA sensors (eg coolant sensors etc)?
3. If I decide to use a turbo ECU - you mentioned about adding wires to the harness, and at the distributor etc. I should have mentioned that the F2T I have came with the harness so surely none of that is necessary? i.e. the only splicing I would have to do would be to get the dash/interior wiring to match up correctly to the ECU? While likely to be a long process this would potentially be easier, and would save mucking around with timing, fuel etc. If I was to do this, would it matter if the F2T ECU was from an auto or manual car?
 

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Yes more research.

1 - Extra injector controllers use boost pressure (MAP sensor) and RPM signal do deliver fuel. If boost rises or rpm climbs they deliver more fuel to the engine. An injector emulator copies the duty cycle ground pulse going to a factory injector and replicates it on the extra injector so as the factory duty cycle changes so does the extra injector, the extra injector will copy the factory injector regardless of boost pressure pressure which is why you use a pressure switch.
Various levels of boost? do you plan on turning the boost control while you're driving? You aren't installing a holset hx40 turbo on the car.

Even with the T3 60trim at 30psi I tune for 30psi, the is no point the engine is boosting 25psi. Boost is 0 or 30psi with a few milliseconds between the two. Same on the stock turbo running 15psi, if I'm boosting even at half throttle boost is still 15psi the engine just gets half as much air at the same boost.
I understand your though process here, I do the same thing, my pressure switches for water meth are set at different pressures and stages (CC to boost) so the first solenoid opens at 22psi and the second at 26psi, but they could both be set for 22psi, either way when I floor the car both solenoids are on and boost is 30psi.

If the turbo on your engine spools 10psi at 3500rpm and hits a peak boost of 15psi at 4100 rpm you installed a turbo that is too big for your engine or have a Honda motor that can't generate enough torque (breath) to get the turbo spooling.

So 1. is no across the board.

2 - Yes all the N/A sensors, vacuum system, dissi...

3 - The auto GT and 5 speed GT harness and ECU are the same. The A and B spec connectors, wire count, functions are not.
If you had the right gen harness for your year car you would still have a lot of work to do.
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You can see on the drivers strut tower the GT harness connects to the red harness through several connectors, these aren't on the N/A harness. One of the larger connectors (white) the goes through the fire wall with the ECU connectors all go to the cluster and dash fuse panel/ relays these would need to be sorted and spliced if the N/A has everything the GT needs to run.

This car was an N/A 91 converted to 88 GT, when we got the car they had put an Aspec GT motor and transmission in, hacked up the harness, pulled the turbo and sold the car.
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We tore it down, I ported the exhaust side of the head and powdercoated some engine parts, I installed the both the Aspec engine harnesses (with fuse box).

After changing all the sensors and all the wires and adding everything else needed the engine bay was complete Yay.
Vehicle Car Hood Motor vehicle Automotive exterior


Now all that was left to do was change the inside firewall harnesses, dash harnesses, cluster... because nothing connected. Boo!

Vehicle door Cockpit Vehicle Motor vehicle Automotive exterior


After all that the interior harness (doors, dome light, fuel pump, trunk/tail lights) would not connect at the dash, I did not want to swap the interior harness or splice 60 wires and we traded the car.

I had all the harnesses and parts needed to convert this car from Bspec N/A to Aspec GT and it was still a pain in the ass job, having to figure out how to splice Aspec GT to Bspec N/A would have been insane.


Adding an extra injector controller to a car:
-Weld injector bungs to charge pipe before throttle body and install injectors.
-Cut the fuel line after the fuel filter and install a T, run hose from the T to both injectors.
-Run switched 12V + and ground to the controller, connect the controllers rpm signal to the negative side of the coil.
-Connect the map sensor vacuum hose to a manifold boost/vacuum source (like a boost gauge).
-Run switched 12V+ to the injectors and run the two injector ground signals from the controller to the injectors.

Install complete.

To set the controller, adjust the start point to the desired boost (in your case between 0 and 1 psi) set the "gain" at 50%, run the car at desired boost and turn down the gain until the Air fuel ratios are correct.

On boost fuel control in 2hours or less.


Look this is your choice I am just trying to give you information and my experience so you can make your own choice .

You can find the 89 626/MX6 wiring diagram here:
PMX626.info //US/Mazda 626 & MX-6/Work Shop Manuals/PDF/

Bspec wiring?

Start by finding all the connection points on the Aspec GT harness that wont connect, draw there pinouts, wire color, where each wire goes and what they do.

Then find the Bspec wiring diagram.
 

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Discussion Starter · #65 ·
By "various levels of boost" I meant that the boost isn't on or off, it depends on the load the engine is under, throttle position etc. I know you say it's only a few milliseconds before full boost but that's not my experience. Eg a car I previously owned (Volvo C30 T5) was tuned to about 20psi but I had a boost gauge and sometimes it would boost to say 10psi and stay there if I was just accelerating moderately in 4th rather than giving it full throttle. The point being if the Mazda is making 8psi I'd assume that sometimes it may only be making 2 or 4 or 6 psi and at each of those points it would need a different amount of fuel.
The problem here is that you say part of the trigger for the extra injector is an RPM signal - correct me if I'm wrong but this would mean that as RPMs increase, so does fuel delivery. But this only makes sense if the amount of fuel required increased at exactly the same rate as RPMs which I can't see being the case.

My other (potentially unfounded) concern is that by adding a single extra injector you have no control over where that extra fuel goes - even if you give the engine the exact right amount of fuel you can't stop (for example) 2 cylinders running very slightly rich and the other 2 being slightly lean if the fuel isn't distributed correctly.

No doubt you have answers to all this as I don't really know what I'm talking about, I'm just trying to think through it all.

I see your point about the wiring though, even if I had a complete parts car with everything I needed it would be a lot of work to swap over.

Questions
1. If I do go down the extra injector route, is there any reason I can't just run the engine "standard" without that extra injector at first to make sure it's all running correctly (potentially go for a brief drive without getting on boost) and then sort out the extra injector? Just because if there is some problem somewhere I feel like it'll be easier to resolve it before the extra complication of the extra injector is a factor.

2. You said in a previous post
"You can run different rate or adjustable rate FMU in place or the fuel pressure regulator and dial in 7psi boost on the factory N/A injectors with higher fuel pressure and a wideband."
Is there any reason this by itself can't be the solution? Runing an adjustable fuel pressure regulator could effectively increase the fuel delivered through the NA injectors, solving the whole problem?

3. I was doing some research into options and came across this one - not sure if you're familiar with this approach but would be interested in hearing thoughts.
AutoSpeed - Electronic Fuel Pressure Increase
It may not be any less work but I feel like it's at least worth considering.
 

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Seems to me there is no solution you can find a problem for.
I am making suggestions and am sharing what I know, it's your job to look into these things and make your own decisions.

By "various levels of boost" I meant that the boost isn't on or off, it depends on the load the engine is under, throttle position etc. I know you say it's only a few milliseconds before full boost but that's not my experience. Eg a car I previously owned (Volvo C30 T5) was tuned to about 20psi but I had a boost gauge and sometimes it would boost to say 10psi and stay there if I was just accelerating moderately in 4th rather than giving it full throttle. The point being if the Mazda is making 8psi I'd assume that sometimes it may only be making 2 or 4 or 6 psi and at each of those points it would need a different amount of fuel.
The lower levels of boost you are talking about is partial throttle, the air flow meter will measure the amount of air the engine is consuming and match it with fuel, it will be less air than an N/A tuned at full throttle. The F2 motor breaths and is real efficient at low RPM's (early torque band) and the vj-11 is a small turbo, you would have to be holding the breaks and giving the car gas or really nursing the pedal in 4th gear (actually looking for that spot in the throttle) for no reason to get the turbo just at the edge of boost.
If you drove the F2T in factory form with a wideband you would see the air fuel ratio's go pig rich in the mid to low 10's when you try tricking the gas pedal into boost, you would also notice the a/r fuel ratio's under boost are really rich all the time from factory, if you didn't have a wideband you would notice gas millage at full throttle and when "tricking the gas pedal" into boost are pretty much the same, you have less fun for the same money.

But none of this matter because it's not about boost, it's about air and the engine gets the most air at wide opened throttle.
The most important A/F ratio's are those at wide opened throttle * the higher the engine rpm the more crucial proper air fuel ratio's become, that is when you don't want the engine to lean out, ever.
At partial throttle the explosions aren't nearly as volatile, A/F's can wander up and down with minimal risk.
So when I mentioned you won't see lower boost level, I was talking about when fueling is most important and the throttles are almost completely or completely opened, tuning is most sensitive and running lean is most dangerous.
You will not see less than set boost with the throttle opened when the engine is getting the most air.

Your other potentially unfounded concern, there are all kinds of ways to set up signal emulators. Life is money or time, want to save a dollar then you spend the time learning and doing, want someone else to do it, spend the money. Because you drive an F2/F2t we can assume you work for your money and aren't wealthy. Do you prefer spending the money you earn or learning and doing it yourself.

RPM: If I simply correct you if your wrong you won't understand and probably wont believe me, If I explain how it works you will understand and you can believe yourself.

F2T target air fuel ratio at full boost 11.8 A/F (low rpm full boost) getting richer to 11.3 A/F (high rpm full boost).
Point 1:
The F2T does run richer as rpm's increase because the time the fuel has to mix with the air gets shorter and shorter, Mazda mapped the car out rich so fuel can cool charge air and has a better chance of mixing with air. I don't know if the amount of fuel delivered remains the same and the amount of air getting in the valves at rpm is smaller (because they are opened for much shorter time) but these motors are happiest (pull hardest) around 11.3a/f at high rpm under full boost, some engines will pull harder leaner than rich but not the F2T, it likes the extra cooling.

So as RPM climb A/F's should get lower in a linear path.

Point 2:
Would you agree that 1 RPM is one full crank rotation and it takes 2 RPM to revolve the cam 360 degrees.
Would you agree that for every 360 degree cam rotation the engine fires each cylinder once. And every 1rpm = 2 spark events on a 4cyl 4stroke.
Would you agree that at 3000rpm the engine is firing 6000 times per minute, at 4500 rpm 9000times and at 6000rpm, 12000times per minute. And that with just those 6 numbers you could easily map out a graft from 100 - 10 000RPM and 200 - 20 000ignitions per minute.
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Would you agree that the number of firing events in an engine is a direct representation of how many times each cylinder opens the intake valves and lets in air per minute based on rpm.
And that this graft also represents the number of breaths the engine take per engine.
And that when you double the RPM's you cut the time the valves are opened for in half.

Injectors are rated in CC/ML per minute (lb/hr) and duty cycle represents how much time they spend opened during that minute, so a 200cc per minute injector firing at 50% duty cycle would deliver 100cc per minute, 25cc/15seconds...
The faster the valve cycles are the less time the injectors have to deliver fuel and the higher the duty cycle must be to deliver the same amount of fuel for each breath of air.

Wait! does this mean the injectors try to deliver the same amount of fuel to each cylinder for every time it fires regardless of RPM and that if you double the rpm you double the engines fuel requirements?

Armed with this simple bit of knowledge, designers of extra injector controllers know exactly how to map out the extra injector controllers fuel deliver, the map curve always stays the same, you just set the boost/vacuum start point based on when you need extra fuel and you set the gain (starting duty cycle). Replace "Firing events per minute" Fuel requirement per minute. Now the three red dot's represent same "Gain" setting at 3 different RPM, you could dial the gain in at 4500 and the injectors will meet the dot at 6000rpm or vice versa.

Because * always make sure the near red line A/F's are right or adjust the gain accordingly.

The Extra injector controller delivers fuel to all four cylinders before the throttle body making it much easier to make a universal map for any size injector because they deliver over 360*.
Individual port injectors are set up the same way (follow the same map) but in batch fired 2X2 injectors each fire every 180*, single fire injectors fire once every 360*. When they start opening, how long they inject for (# of degrees) and how much fuel they deliver all need to be dialed in.

But this only makes sense if the amount of fuel required increased at exactly the same rate as RPMs which I can't see being the case.
Can you see it now?
(no offense but this is a question you could have answered with a bit of searching, thinking and common sense).

The extra injector controller also follows the map sensor voltage 0-5V signal it receives and increases the fuel as voltage increases. So if my controller is set to come on at 15psi and I set my manual boost controller to 21 psi and set the gain to say 25% and A/F's are perfect from spool up to redline then I turn the boost down to 17psi or up to 22psi the A/F's will stay the same.
If the black line on the graft represents fuel delivery at 17psi the red line would be fuel delivery at the same gain but higher boost, say 20psi:
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2. You said in a previous post
"You can run different rate or adjustable rate FMU in place or the fuel pressure regulator and dial in 7psi boost on the factory N/A injectors with higher fuel pressure and a wideband."
Is there any reason this by itself can't be the solution? Runing an adjustable fuel pressure regulator could effectively increase the fuel delivered through the NA injectors, solving the whole problem?
Yes but this would ignore rpm and you would have to set A/F's for 11.3 at high rpm, they would likely be 11.3 or richer at lower rpm .
Running higher fuel rail pressure whenever your on boost would tax the factory fuel pump, a high volume, high pressure pump would be required.

There is a 2nd dilemma, say you get a 6:1 or 12:1 or whatever FMU and 6:1 or 12:1 fuel rail pressure to psi signal isn't enough with base fuel rail pressure set factory (34-40psi) your only option is to increase base fuel pressure and be rich all the time to get the right peak boost, peak rpm air fuel ratios.


3. I was doing some research into options and came across this one - not sure if you're familiar with this approach but would be interested in hearing thoughts.
AutoSpeed - Electronic Fuel Pressure Increase
It may not be any less work but I feel like it's at least worth considering.
That is pretty sketchy and if I read this correctly :
"When the electronic switch is activating at the right time, wire the solenoid to the on-board relay so that as the switch clicks over, the solenoid closes. (Full wiring instructions for switching things is covered in the kit instructions.) "

The kit uses a normally opened solenoid valve, so if the relay, control board switch, solenoid valve or connections fail, the solenoid valve stays opened, fuel pressure stays factory and you need a new motor.
That is a lot of faith to put into cheap controller with flimsy screw down wire connectors that often loose grip of the wire.

I also don't think this kits for forced induction vehicles, the N/A and GT have a 1:1 rising rate regulator, for every one PSI of boost pressure from the vacuum port the regulator gets fuel rail pressure is increased by 1psi.
This is to make up for the pressure inside the intake manifold, if fuel pressure is 40ps and boost is10psi the injectors will deliver fuel at a 30psi fuel rail pressure.
Because his kit uses a ball valve to regulate high fuel pressure, it's a fixed fuel pressure rate from the time the solenoid valve closes and the factory 1:1 FPR wont change fuel pressure because the pressure is higher after the FPR.

Years ago I came up with an Idea for something similar for the F2T to go above 15psi on factory injectors.

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This set up has failsafes, the solenoid valves is normally closed so if the pressure switch, relay, solenoid or wiring fails fuel pressure stays higher and the engine will run richer at cruise and idle but doesn't blow up.

This would be the best way to run a FMU without ending up rich at idle and cruise.
The FMU would vary fuel pressure based on boost to fuel pressure ratio and because of the pressure switch/solenoid valve never effect boost a/f's below a certain boost allowing to dial in initial fuel rail pressure and the effects boost pressure has on increasing the fuel delivery when extra fuel is needed.
Doing this on factory injectors will only get you so far, even with a high pressure high volume pump there is a limit to how much pressure the injectors can close under and the fuel system can handle.

You could run slightly larger than factory injectors and lower idle fuel pressure to correct idle and cruise a/f's, I wouldn't run a fuel rail pressure below 25psi at idle, the adjustable 1:1 FPR's I run default to 40psi at atmosphere (vacuum hose off) no matter where they are set bellow that at idle vacuum, or you can adjust the screw with the vacuum port off and eventually raise pressure above 40psi at atmosphere and it will stay high at idle.

All that is needed is a performance fuel pump, 4 high impedance injectors that fit in the fuel rail that are close enough in size to factory to deliver factory fuel amount at 25psi (minimum) fuel rail pressure (injector calculators online will calculate this) and fit the F2 fuel rail, an adjustable fuel 1:1 fuel pressure regulator, a fuel management unit, solenoid valve, relay, pressure switch, hose, some T's, hose clamps, a wideband, some math, trial and error and luck to dial in how many psi rail pressure is required per extra psi boost.

All that and you might get an okay fuel A/F curve with spots (like atmosphere pressure) the engine is to rich.
You can't increase injector size beyond this point without idle cruise issues and are limited to maximum safe fuel rail pressure on slightly larger injectors as your peak fuel delivery.

An extra injector controller cost less, delivers better fuel maps, cools charge air and completely vaporizes with the fuel in the intake manifold and when you run out of injectors adding mods and running more boost, just install larger ones and turn down the gain.

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I say:
-Speeduino is your most versatile option, one of the most affordable and a lot of work.

-An extra injector controller is the second best way to regulate fuel in boost, the other of the most affordable solution and the least work.

-An injector emulator and extra injector set up properly with a bit of AFM tweaking can offer a good A/F curve because it will follow the ECU's injector duty cycle.

-An FMU would be the second most work, most expensive and yield the worst A/F curve.

-The "autospeed electric fuel pressure increase" will blow up your motor.
 

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Are you saying the Volvo didn't have enough off boost power to maintain speed up a hill or when on flat pavement without engaging boost? Is this because of the all wheel drive?

If you want to get to the speed limit and drive a steady speed with a turbo car you do if off boost, if you want to accelerate fast you floor it.
If you want to dink around with the pedal and think partial throttle and partial boost are fun, get out of the fast lane.
 

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Discussion Starter · #68 ·
Seems to me there is no solution you can find a problem for.
I am making suggestions and am sharing what I know, it's your job to look into these things and make your own decisions.
Yes I appreciate that, hope I don't come across as being argumentative, I just want to identify potential problems before I actually do the work so I'm prepared for having to solve them.
Don't expect you to be able to tell me what to do at every step of course.
As you noted there's probably also things I've asked that I could have worked out myself, the problem is that I'm very new to all this and while I'm happy to learn I'm not going to be able to grasp everything overnight. I'd prefer to look stupid asking a dumb question than blow up the engine!

Yes but this would ignore rpm and you would have to set A/F's for 11.3 at high rpm, they would likely be 11.3 or richer at lower rpm .
Running higher fuel rail pressure whenever your on boost would tax the factory fuel pump, a high volume, high pressure pump would be required.

There is a 2nd dilemma, say you get a 6:1 or 12:1 or whatever FMU and 6:1 or 12:1 fuel rail pressure to psi signal isn't enough with base fuel rail pressure set factory (34-40psi) your only option is to increase base fuel pressure and be rich all the time to get the right peak boost, peak rpm air fuel ratios.
So if I understand correctly you're saying that there would be a similar problem to what I'd have if I ran the F2T injectors off the NA ECU, i.e. to set the pressure to deliver the correct fuel under boost it'll be too rich at cruise or idle?

the N/A and GT have a 1:1 rising rate regulator, for every one PSI of boost pressure from the vacuum port the regulator gets fuel rail pressure is increased by 1psi.
This reminds me of this video I watched:
🛠 Under Pressure - Why You Need A Fuel Pressure Regulator | TECH TUESDAY | - YouTube

It sounds like you're saying the Mazda has what he's talking about from the factory?
I was going to ask whether I could simply get a bigger fuel pump, get a FPR like he talks about in the video, and adjust it so that it delivers the correct amount of fuel at idle but then increases fuel as boost increases?
Bearing in mind that at this stage I only plan to run stock boost levels.
Maybe I need to re-read what you wrote a few times to understand if there's issues with doing it that way. I'm just not sure what advantage your solution (with the diagram you made) would give me in my case, you say it's suitable for going above 15psi but I'm only going to have say 8psi of boost.

Are you saying the Volvo didn't have enough off boost power to maintain speed up a hill or when on flat pavement without engaging boost?
Certainly wasn't a case of not having enough power off boost, I drove an NA version of the same car/engine and it had more than enough power for going up hill/overtaking etc, I assumed it was how the tune was set up eg to get better fuel economy or something.
But really it was a much more modern car than the Mazda and a bigger turbo so probably not a good comparison.

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I think my approach is going to be to get the engine in the car, get it all wired up with the NA ECU and injectors and sensors etc, and make sure it's running ok off boost and can drive around the block etc - and then implement whatever fuel system I decide on afterwards.
 

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Are we in agreement about engine fuel requirements and rpm?

Remove the clip holding the wastegate actuator/flap and pull the wastegate shaft out of the swing valve and let the wastegate sit opened, this will cause insane boost lag and give you maybe 3psi at wide open throttle at red line.
Run premium gas.

The advantage to my design in the diagram was written but you would have to understand (visualize, modify and design in your mind) a fuel system to catch it.
The Autospeed is a similar "Ghetto" version of my design.

The set up in the diagram allows you to run 2 base fuel rail pressures, one off boost and one on boost (or ), this allows fuel rail pressure to change as soon as boost starts, the diagram starts at 15psi () because that's when F2T injectors run out.
The design allows you to run factory air fuel ratio's, fuel pressure and injectors and keeps everything running factory until more than factory fuel is required.

The difference between my and autospeed design is that it uses a FMU instead of a ball valve to control the second stage fuel rail pressure, while both allow you to set stage 2 fuel rail pressure my system runs a rising rate FMU that changes fuel rail pressure with boost pressure at adjustable rates 1:1 to 12:1.

The Mazda and many F2 cars run 1:1 fuel pressure regulators even though the engine isn't ever going to see boost.
How they work is there is a spring and plunger and diaphragm inside the fuel pressure regulator (like a wastegate or a blow off valve), under engine vacuum suction pull tension from the spring and makes it easier for the fuel to push the plunger opened, at atmosphere the spring tension (about 40spi) has to be moved by the fuel, under boost the diaphragm adds boost pressure to the springs pressure increasing spring tension bay the exact amount of boost.
The factory fuel pressure regulator is in a bad spot, it sits before cylinder 1's injector, it can allow fuel that should have gone to cylinder 1 out and cause un-even fueling at that injector, the higher fuel rail pressure gets the higher the risk, so running a fuel pressure regulatro ar the end of the fuel rail is better than the factory location. Higher pressure does not mean higher volume, pressure increases because of the resistance in front of the fuel so as pressure increases the fuel pump is moving less.

The problem is a quality FMU costs as much as an extra injector controller, everything required cost more than stand alone would.

Very few FMU's where variable rate back when I came up with the idea, I got it from reading about the synapses synchronic fuel pressure regulator, the first one I found with variable rate selection.
Back then it was 500$ us, I though the company disappeared but:
Synapse Synchronic Fuel Pressure Regulator FMU (FPR)

Sounds like the volvo had ECU controlled boost and all kinds of other fancy unnecessary fuel saving programming.

The stroke of the F2 motor makes it act differently than modern motors and most other imports of the era. Most cars have a progressive power band but the f2/f2t has a sudden power band (power means torque).
Here is a factory bone stock F2T dyno with the factory boost solenoid at the turbo.


Rectangle Slope Font Plot Parallel


The big hump is torque and the little one HP, notice the powerband fluctuate at about 3000rpm and drop at 4000rpm, that is the factory turbo solenoid valve opening and closing, opened it delivers over 8psi, closed the wastegate makes 6.7psi.
When it closes the extra exhaust manifold pressure in the comp housing push the wastegate flap opened and boost falls on it's ass.
The torque curve peak shows how much air the engine is sucking in and burning at it's most efficient point, if the engine was 100% efficient it would be a straight torque line above 170 or 180.

Anyway this shows why it's harder to run partial boost on the F2T than other small displacement imports.

Outlaw engineering performed this dyno running a set of it's thermo gasgets (blue lines) and claim that the HP gains are from cooler intake charge air temps, the manifold still runs coolant and EGR through it, the gaskets make the manifold even longer than it is factory which increases low end torque and decreases high en torque which is why the blue lines drop after 5252rpm. Cooler air would be even gains across the board, cooler air has more oxigene and generates more power always. Engineering but don't know how to read a dyno chart. Unlike some mods they acturallu made more useable power but just to dumb to know why. Some mods cost power across 90% of the powerband and for a couple hundred rpm show 10hp gains and the company pitches 10hp gains when the car is slower.

Torque is measurable power, HorsePower is bullshit, 1 horse power is equal to the strength of a horses leg, blah blah blah, put a 4hp motor (100% efficient, electric) in something the same weight as a horse and race the horse with it.
 

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Discussion Starter · #70 ·
Yes I think I understand what you mean about the RPMs etc.
I'm not actually opposed to running the extra injector etc, I can see how now it should work effectively, but this is a project car so I might as well explore different options that are available.

I would definitely agree that your design (running the FMU instead of a ball valve etc) is superior to the Autospeed one with the ball valve.

So compared to my proposal of simply upgrading the fuel pump and running a boost reference FPR - the main advantage of yours is that it gives 2 different base fuel rail pressures for on and off boost... I guess the question is whether this is really necessary when running only say 8psi of boost?

That power band graph is quite interesting, not sure I've seen that shape of band for any other car and seeing that I understand what you mean about it being unlikely to be running at partial boost.
Probably a bit of a tangent but I'm not sure I understand the part about "power means torque", I assume you mean that power and torque are related?
(As an aside I agree about horsepower, at least in Australia we use kW which is an actual measurement of energy)
 

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You should explore the most efficient, affordable option for fuel supply.

Let me rephrase, power means Newton Meters. KW is the same as HP it is not a measure of force but a mathematical equation based on torsion (be it FT/B or NM), energy is not force when it comes to combustion engines, it's a calculation.

Only torque or NM or what ever measure of torsion can be measured at the wheels or crank. The other number is math.
If your car shifts at 6000 rpm and you lie to the dynomometer and say it's running 12000 rpm in the last gear, the HP or Kw will almost double at the same force/torsion/acceleration, the wheel dyno doesn't measure engine rpm it reacts to wheel acceleration/force, rpm must be entered after or monitored during the dyno run.

The reason I like the F2T is because it can get a turbo spinning fast (torque/nm/breath...) with proper boost contorl, set up and turbo the turbo will keep the engine breathing to redline, it makes power quick and keeps making it. This equals wheel spin on the track and a killer on the street, what i mean is it wins on a role, I am not saying street racing kills people. In fact I recommend to everyone I meet to brake every rule and law they have heard of or don't like, otherwise we are governed like an ECU.

If you can run an FMU at factory fuel pressure and supply proper A/F's under boost than my design is not necessary, you need to look at and use an injector to fuel pressure calculator to find out if that is possible. From what I calculated you would need to run 100psi fuel rail to match GT injectors peak flow.
 

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Discussion Starter · #72 ·
If you can run an FMU at factory fuel pressure and supply proper A/F's under boost than my design is not necessary, you need to look at and use an injector to fuel pressure calculator to find out if that is possible. From what I calculated you would need to run 100psi fuel rail to match GT injectors peak flow.
Ah yes ok.
So my assumption was that if the fuel pressure is meant to be 40psi (workshop manual says 34-40) and you add say 10psi of boost then your FMU or FPR needs to increase fuel pressure by 10psi (to 50psi total).
I had a look at an injector to fuel pressure calculator and it seemed to back this up.
However I wasn't 100% sure what the F2 rated duty cycle and flow cc/min specs are so that could be why my maths don't add up to anywhere near the 100psi you calculated...
 

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A 210cc injector at 40psi will deliver 332cc at 100psi, engine boost pressure must be subtracted from fuel rail pressure.

Not my math just an online calculator:
Fuel Injector Calculators
 

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The factory work shop injector ratings (in the 88wsm and 92wsm) are the same.
And with other basic info on the 2 cars it could all be calculated but...
. . . . . . . . . . . .N/a . . . . . . . . . . . . . . . GT
HP . . . . . . . . . 110 . . . . . . . . . . . . . . . 145
TORQUE . . . .130 . . . . . . . . . . . . . . . 190
Ohms . . . . . 12 - 16 . . . . . . . . . . . . 11 - 15
CC/15 sec . .44 - 61 . . . . . . . . . . . . .73 - 90
CC/min . . . 176 - 244. . . . . . . . . . . 292 - 360
Variation . . . 38.63% . . . . . . . . . . . . .23.28%

The variation on N/A injectors CC (39%) make it very hard to come up with the N/A injector CC delivery at an 85% duty cycle.

So a different approach would be: The N/A tune running wide opened throttle requires X cc of fuel.
If you add a turbo and run 15 psi (or 1 bar) you need 110% more fuel than X cc.
If you run 7.5 psi (or 0.5 bar) you need 55% more fuel than X cc.
55% Divided by 7.5 psi = 7.3333333... % cc delivery increase per PSI boost.

Using the injector to fuel pressure calculator and an injector size of 100cc at 40 psi fuel rail pressure
@ 46.2 psi the injectors would deliver about 107.33 cc of fuel or 7.3333% more fuel. (Because the calculator doesn't use decimal for CC flow rate 1000CC at 46.2psi = 1074cc / 7.4% more fuel)
Because fuel rail pressure must increase to match boost pressure we add 1 PSI to 46.2psi to get the same delivery =
47.2 psi, subtract the base rail pressure (40psi) and you get 7.2psi fuel rail increase per PSI of boost.
Boost-- Fuel Rail pressure
0 . . . . . .40psi
1psi . . . 47.2psi
2psi . . . 54.4psi
3psi. . . .61.6psi
4psi . . . 68.8psi
5psi . . . 76psi
6psi . . . 83.2psi
7psi . . . 90.4psi
7.5psi . .94psi
8psi . . . 97.6psi
9psi . . . 104.8psi

So on paper a 7.2:1 fuel pressure regulator/FMU is what is required.
To run 90+ psi fuel rail pressure?
How fast does a FMU change fuel rail pressure? Is it fast enough to keep up with the speed of spool? (Raise fuel pressure from 40psi to 94psi as fast as boost comes on?
That sure doesn't leave much of a window for boost spikes and cool nights with damp cold dense air without passing 100psi fuel rail pressure.
Can the 30 year old injectors close under this fuel rail pressure?

I decided years ago that more fuel pressure was not the right way to supply more fuel to the motor.
I don't even like the fact that at 30spi boost my fuel rail pressure has to be 70psi 50% of the time.

You should start by searching and looking into extra injector controllers, some of the new ones can even pull ignition timing.
HKS, Blitz, SDS, AEM, Split Second, Unichip I driver (low price), ReFlex Lite, URD, 034 motorsports... all make additional/extra/supplemental injector controllers.

Or look into making your own emulator or controller
Build your own Additional Injector Drive

Extra fuel injector controller
 

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Discussion Starter · #75 ·
Alright so I think I must have been getting confused about pressure vs flow.
i.e. my original thinking was that if there is say 8psi boost, I would need 8psi of extra fuel, so total 48psi.
But actually what I need is not 8psi of fuel, but enough psi of extra fuel to raise the flow rate from 176-244 CC/min (NA spec) to 292-360 (F2T spec).
If this is correct then the results of the injector calculator make sense... if I put in an actual fuel pressure of 97.6psi (which is what your maths calculated the required pressure at 8psi of boost to be) then it gives an "actual" flow rate of 340 cc/min which seems to be correct.
Rectangle Font Parallel Number Screenshot


sorry a bit slow but I understand it now.

I am still definitely going to look into the extra injector controller option, as I understand your concerns with this option. I guess the reason I wanted to explore this option is that based on preliminary research it will cost around the same, and to me it seems simpler - all it really requires is two parts, a higher rated fuel pump (easy) and an FMU (relatively easy as I can borrow a fuel pressure gauge from my mechanic).
So even if it's an inferior option, the fact that it's simpler is better for someone like me (who doesn't really know what he's doing) because it will be easier to get right, even if it's not possible for it to work as effectively as another option.
(This is the same reason you suggested the extra injector over an aftermarket ECU right - an aftermarket ECU is "better" but is much more complicated to implement.)

-----------

Completely different subject - to install an AFR/wideband gauge - is it possible to take the signal from the factory O2 sensor for this?
 

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You're almost there.
Flow: If two people blow into each end of a straw at the same pressure air goes nowhere.
Think of fuel in the fuel rail as one person, boost in the intake as the other and the straw as the injector.
Fuel pressure. Boost Pressure. Result
. 20 . . . . . . . . . . . .20. . . . . . . . . 0 fuel injected
. 20 . . . . . . . . . . . .10. . . . . . . . . 10psi fuel injected
. 10 . . . . . . . . . . . .20. . . . . . . . . 10psi air pushed through the injector and into the fuel rail when the injectors opened.

To flow the same amount of fuel as the injector would at atmosphere (no boost) with a 40psi fuel rail pressure when the engine is under boost, fuel rail pressure must be increased by the amount of boost that's in the intake manifold.

Fuel, Boost, fuel pressure out the injector.
.40 . . .0. . . . 40
.50 . . 10. . . .40
.70 . . 30. . . .40

That is why when the simple equation based on a basic/general 110% more fuel for an equal amount of extra air under boost came to +6.2psi fuel per pound boost I added 1 psi to 6.2 to cover the manifold boost. So when you use the injector calculator to estimate fuel delivery based on pressure you must subtract engine boost psi from "Actual Fuel Pressure"
So the 97.6 you entered for 8psi boost should be 89.6 psi because that will be the actual fuel pressure.

I see you used the upper calculator.
Lets use this opportunity to understand HP and Torque (Kw and Nm).
The F2T puts out 145hp at the wheels not the crank, so a 15+% increase should be used to estimate HP at the crank.
But go back to the dyno graph of torque and HP for the F2T and look at the gap between torque and HP. If we fuel the F2T based on the tiny HP map (that is a calculation based on torque and RPM) we would not have enough fuel for the air the engine is actually breathing in and burning across the torque band.
The small boost solenoid bolted to the turbo is what causes the drop in torque above 4000rpm, most remove it, your harness and ECU can't operate it.

Without the solenoid valve causing the wastegate to open more at 4000 the power band would look more like the lines I added to the dyno chart:
Rectangle Product Slope Font Plot


So now the engine would be making over 170hp above 6000rpm.
The new torque drop at 5000 rpm is the small factory turbo and weak wastegate, with proper boost control the torque band would drop less and HP numbers would be higher, also I did not add to the early torque band where the solenoid is closed below 3000 rpm and when it opens at 3000 rpm, without the solenoid the torque band will climb faster and be at the same peak (4000rpm) by 3000rpm, This will make the HP band larger from 2600 - 4000rpm.

For the injector calculator, you should replace HP with torque, I would use 190 (we don't know what weather, what type of dyno this probe ran on or the condition of the engine) wheel torque + 15% = 218
So enter 218 for crank HP, that is a safe guess at what you are fueling for (better rich/safe than lean/sorry).

Rectangle Parallel Font Number Logo


Hp and Torque.
Torque is what gets the car moving and the rpm's climbing, Horse Power is a measure of momentum, the more inertia something spinning has the easier it is to get it spinning faster. But torque will make RPM climb faster than HP.
In both the original and edited Ford probe 2.2L dyno chart the car will be accelerating fastest at 4000rpm. By holding the torque line as steady as possible to redline the engine will pull harder to redline. (Torque generates hp through math).

However there are times when engine inertia accelerates the car faster than torque because the engine doesn't make enough torque to get the car moving but thanks to inertia the small amount of torque can accelerate the car faster above 5252rpm. Like in this dyno:
Rectangle Organism Font Slope Parallel


A vehicles acceleration line is the torque band below 5252rpm and above 5252rpm it's the HP line ,which is a mathematical equation representing the effect inertia has on torque over 1minute.
The bottom line is it's all about the torque, the faster the engine makes it and the longer the engine holds it the faster the car will be and the higher the calculated HP will be.

In the 2 dyno's and engines Mazda and Honda took two very different paths, Mazda added stroke to generate toque early and make the engine pull right away, Honda reduced stroke and lightened rotating mass and there only goal was to take advantage of inertia and the honda engine pulls hardest above 5252rpm.
The difference is that it's fairly easy to get the mazda F2T hold torque to redline and redline can be raised.
It is very difficult to get the Honda to lots of torque below 5252 this means the honda will need at or above 5252rpm when flooring it and to rev high so it doesn't fall below 5252rpm in the next gear, If your caught in the wrong gear or shift to early you loose, as you shift to larger gears resistance against inertia gets larger and the car gets slower.
The mazda you can shift at 5000rpm or redline or anywhere between and still be in the powerband in the next gear, the higher the gear the more the resistance which makes the engine breath harder and the car gets faster.
So with the F2T every car I have raced that is the same speed in 3rd is slower in 4th and 5th.
You will be running a transmission with shorter gears this will slow the engine a bit, Load makes the engine and turbo breath more and shorter gears reduce the load. The F2T will climb in rpm at the same speed but the shorter gears means the wheels turned less times on the pavement. With mods and more boost... this would have far less effect at which point the shorter gears will piss you off because your always at redline having to shift (the same way the F2T transmission pisses me off).

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I get that you are looking for the easiest option, I wrote instruction for installing and operating an extra injector controller.
Have two universal injector bungs welded to the metal charge pipe.
Connect some wires, a vacuum line, run fuel to the injectors.
Set start point boost (0-1) drive car and turn down gain until A/F's are correct.

The FMU goes under the hood so to make adjustments you must pull over, open the hood, guess, try, pull over again...
Installation requires making sure everything you install and everything factory can handle more than twice the factory fuel rail pressure...

I could install and tune an extra injector controller faster than simply custom installing a performance fuel pump in an F2 gas tank.

Right now to you the idea of extra injector control seems more complicated because you haven't looked into it.

The trick to learning is: Do not try to relate what your learning to what you already know because this usually leads to misunderstanding, try to learn and understand the new thing on it's own, once you understand it forwards, backwards and upside down then incorporate it with the rest of what you know. This way you are working with something you understand instead of something you get the idea of and won't end up designing something like the "autospeed electronic fuel pressure increase" or claiming thermo gaskets add power from cooler air when clearly it's from longer intake runners (2 examples of design without knowledge).

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Asking if it's possible to install the wideband sensor in the o2 sensor bung would be bad enough.
Are you asking me if the single wire 0-1V factory narrow band signal can replace a highly accurate 5wire Lambda wideband sensor. The answer is no.
But with some widebands (like the innovate motorsports LC1 or LC2 wideband controller and gauge) one of the auxiliary outputs can be used to deliver a more accurate (and programmable) narrow band signal to the factory ECU instead of the less accurate factory o2 sensor.
The wideband sensor must be installed 12-18inches (or what the directions specify) after the turbo, a bung must be welded to the exhaust pipe for the sensor to screw into.

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On a side note I mentioned that automatic and 5speed ECU's are the same, and they are but there have been 2 instances, 1 an auto N/A 626 and my shop partners 626GT auto converted to 5speed transmission, tricked auto gear selector signal and safety switch lock out. Neither car would start without the cluster connected to the harness, 5Speeds will start without the dash and cluster. I don't know if what part of the system on the automatic needs signals from the cluster or how it's gets the ECU to refuse to start the car but there is a tiny possibility that a cluster signal could be required for an auto ECU, this could also be a signal from the cluster to the transmission controller thats sent to the ECU and without the transmission controller connected the car starts? But I though I should mention it since the A and B specs have different clusters.

Oh and also a guy in Australia bough a digital A spec cluster from me, I made an adapter using a 91 N/A cluster connector and 88 dash harness connectors to connect between the A cluster and B harness, he couldn't get the car to start and never mentioned he had an automatic or thought he needed an automatic digital cluster, He asked to buy one, I reset the mileage too zero and waited for him to pay the shipping and cost of the first cluster I shipped to OZ. He never did, The auto cluster sat in a box for 18years, I put a 5speed face on the cluster and it is going in my 666GT. 0KM.
 

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Something you can do with the factory turbo solenoid valve is use it as a boost controller exactly the way it is.
According to the workshop manual the max boost from the wastegate alone is 6.5psi and when the solenoid is powered and opened boost is 8.7psi max. The solenoid is adjustable, using a toggle switch and possibly a relay, you can adjust the solenoid to deliver 7.5psi (if that's what you want to run) and be able to toggle between 6.5psi and 7.5 psi.

Another way to run actual wastegate pressure that matches the manifold pressure on a gauge is to have a nipple welded to the charge pipe (before any extra injectors) and run a hose from the nipple to the wastegate (no solenoid, block the turbo port), instead of the wastegate being controlled by boost at the compressor outlet it's controlled by the same pressure the manifold is seeing, so if the wastegate actually opens at 7.5psi you will see 7.5 psi on you gauge, but 7.5psi at the comp housing would be 6.5psi or less manifold pressure.

Having two stages of boost control is cool but taking a wastegate signal from the intake pipe will stabilize boost a lot and hold it better, if you port the wastegate hole in the turbine housing this also helps deliver consistent boost.
Running the wastegate off the charge pipe and porting it won't increase peak boost they will just deliver it far more efficiently across the power band and make the car faster.
 

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Discussion Starter · #78 ·
Thanks for the info about the solenoid etc, I think I'll look at that sort of stuff once the engine is actually in the car and running.

I must admit I don't understand what you mean by replace HP with torque for the injector calculator but I will re-read your post with fresh eyes tomorrow.

You mention the ECU, I just wanted to revisit the wiring option one more time.
You previously discussed getting an F2T ECU would be a lot of work because of all the wiring you'd have to hack together, and you had an example of a 626 you bought, etc.
But this is only the case if I was to run an A spec ECU, right?

So if I ran a B Spec F2T ECU, and swapped over the necessary sensors etc on the engine, the existing dash harness should plug in fine, and there might just be a little bit of extra wiring to do around the engine bay?

There is another option I will try and pursue, I have come across someone who has a turbo Ford Telstar (same car/engine etc as 626) that he plans to part out and get rid of eventually. He's not sure what year it is so no idea if A or B spec.
Ideal scenario would be that it's B spec, I can get the ECU and all wiring from him, the dash wiring will plug in fine, and everything can run as factory.
If it's A spec, it would still leave me with the same issue you had with that 626 you mentioned that you sold because it was too hard. Sadly I suspect this is the case as most turbo models I've seen over here are 1988-89 models.
 

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I must admit I don't understand what you mean by replace HP with torque for the injector calculator but I will re-read your post with fresh eyes tomorrow.
Calculate fuel requirements based on peak numbers, torque or HP which ever is higher, if you have a Mazda F2T use torque if you have a Honda civic use HP.
Always over estimate fuel requirements then turn fuel delivery down to correct levels (safe tuning) .

If you get a Bspec donor than all the connectors will match, you will need the Bspec wiring diagram to know which wires are different. You need to run the GT headlight and engine harness and connect them and change pinouts/add wires for the GT harness or swap the necessary dash and firewall harnesses. The floor/door/trunk harness should plug to the GT harnesses fuse/ecm... boxes/harnesses.
 

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Discussion Starter · #80 ·
Calculate fuel requirements based on peak numbers, torque or HP which ever is higher, if you have a Mazda F2T use torque if you have a Honda civic use HP.
Always over estimate fuel requirements then turn fuel delivery down to correct levels (safe tuning) .
Over estimating is fine but I still don't understand why you just select the higher out of torque and HP, the calculator is programmed to use HP so if you use torque it will give a different result? If you do that to over estimate and be on the safe side then that's fair enough but it seems a bit arbitrary because I could choose to use pound-feet or Nm and they're both torque but will give different results.
 
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