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Discussion Starter #1
Here's a clip of 1/2 throttle rolling onto the freeway. Still tuning on the spark advance and ve table. Appears I can continue to pull fuel under light throttle as well to clean up the afrs before the boost comes in.


Any tips for knock prevention/ monitoring? I havent set up knock prevention in the ms3 yet as I dont have the hardware for it. That will likely be the route I take whenever I feel like going that route. Currently I check my plugs and use a camera on my pistons to check for any pinging when I make changes in the timing. Don't know how accurate that is but its the best I was able to come up with lol.
 

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Discussion Starter #2
Here's 6 psi with boost controller shut. My boost gauge, sourced from the throttle body before the blades is showing 8lbs when my map is showing 6 psi. I imagine that's due to a restrictive intake set up and thats why my wastegate is opening prematurely. Do wastegates also open a partial amount to maintain boost or is it more or less when the diagram overcomes spring pressure it simply opens. I can't hardly tell the difference in sound since I don't run anything more than a downpipe. Any input appreciated

 

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Here's 6 psi with boost controller shut. My boost gauge, sourced from the throttle body before the blades is showing 8lbs when my map is showing 6 psi. I imagine that's due to a restrictive intake set up and thats why my wastegate is opening prematurely. Do wastegates also open a partial amount to maintain boost or is it more or less when the diagram overcomes spring pressure it simply opens. I can't hardly tell the difference in sound since I don't run anything more than a downpipe. Any input appreciated

Your boost gauge is sourced from the throttle body before the blades? Do you mean throttle body flaps?
You should be taking boost readings after the throttle body flaps from the intake manifold, I always take mine from the vacuum line going to the fuel pressure regulator so I can monitor the boost that the FPR is reading (mechanically).
Your wastegate boost signal should be taken from the hard pipe before the throttle body and not at the compressor housing, this way the waste gate operates at the same boost pressure as the engine instead of the boost building in the compressor housing. So the waste gate will open in sequence with the actual boost and not open early or at lower intake pressure.

External wastegates open partial amounts to maintain steady boost otherwise it would be impossible to give a pressure rating to the wastegate springs because turbo size and set-up would result in different boost on every car running that same size spring.
For example my 89mx6GT runs a 38mm Tial wastegate with one bar (14.5psi) spring. If the wastegate opened a fixed amount at 14.5psi and say maintained 14.5 psi on a T3 60trim (flow rate of up to 36lb/min) then I put a factory IHI turbo (flow rare up to 21lb/min) on the car and the wastegate opens the same distance at 14.5psi as with the 60trim than boost would drop because too much exhaust would bypass the turbo through the wastegate. Than with a TD04E (flowing up to 55lb/min) at that same distance of wastegate travel boost levels would be at 22psi because of the extra flow of the larger turbo over the 60trim.
And that would be under perfect circumstances at the right rpm in the right gear, because the engine breaths differently through the rpm range and in all the different gears boost pressure would be all over the place throughout the powerband and throughout the gears.

So the wastegate flap, spring and air bladder are constantly moving to maintain spring rate boost.

When using a boost controller, the pressure hose going to the wastegate "T" 'd and the boost controller runs off one port, the other goes to the wastegate lower fitting, the out port of the boost controller goes to the top port of the wastegate with another T in it venting to atmosphere. This allows the amount of boost bled off before the wastegate actuator to act against the air bladder through the upper wastegate port to keep the spring from oppening too far because the boost at the wastegate flap is now higher than the spring rating and actuator boost source pressure. So say you have an 8lb spring and you set the boost controller to run 12psi, you are bleeding 4psi off from the wastegate actuator, the wastegate actuator receives 8 psi but the waste gate flap gets exhaust pressure of 12psi engine boost against it and the 4psi the boost controller bleeds off pressurizes the top of the wastegate bladder and counter acts the added exhaust pressure on the wastegate flap to maintain a perfect 12psi boost.


Does the MS3 not have select-able knock sensor signals? If it does you could probably use the factory knock sensor and set the MS3 to work off it's signal. A knock sensor is just a vibration sensitive sensor that receives a signal (ground or positive or Ohms...) and when vibration/frequency/shock reaches a certain point the needle sensor in it's center vibrates, makes continuity and sends that signal back to the ECU alerting it of pigging or knock.

Aren't you running expensive forged pistons? Your knock detection technique isn't the best solution for tuning a vehicle, pigging can cause pistons to move around causing wear on the piston bellow the rings and also cause pitting on the tops of the pistons, these pits can be hot spots, areas that hold more heat than they should, at high boost these areas can get hot enough to ignite the fuel in the cylinder causing extreme predetonation damage to the engine.

Get and set-up knock control to prevent damage during tuning instead of looking at the tops of the pistons to find out if you ruined the engine.

You should run your boost gauge and Map sensor on the same port just to confirm both are accurate, you shouldn't be seeing 2psi difference before and after the TB at full throttle, but then again I have never and never heard of anyone taking boost readings at the throttle body before the flaps. People have taken them at the compressor housing and the intake manifold to measure intercooler and piping pressure drops.
 

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Discussion Starter #4 (Edited)
Mazda Carnage you the man. Thanks for the input.
The megasquirt sees its MAP source on the intake manifold after the blades off one of the factory ports, i have a simple boost gauge i used to run I installed on the throttle body before the flaps on the charge piping side that T'd off the wastegate source. I thought thats how I would overcome the pressure loss of the system but still feed an even 8lbs through the throttle body. Seems like it's pointless currently and likely showing me a reading thats is not useful. Ill set the boost controller as youre suggesting too! As currently its just removed off the car. Ms3 does have knock sensing capabilities i can do some digging to see if there is info on the stock sensor to see if they are compatible but if not a GM sensor should work too maybe?

Theres a reason I havent turned the boost up. Mainly cause I'm still learning on the tuning aspect and how to make the thing last. Id rather not blow it up so leaving it conservative allows my to learn and grow with the thing. Make more hp as I learn more.

I will verify accuracy on the boost gauge hooked up to the manifold, then put it back before the throttle body, at the same time reinstall the boost controller plumbing in the order you stated. If it indeed is a 2psi drop across that throttle body id say thats fairly restrictive. Nothing a couple more psi can't fix but on a side note, looking at our dual blade throttle body is there any advantages to this or is it more or less an experiment from Mazda and Ford? Are there other cars out there utilizing a dual blade throttle body where one port is smaller than the other? Would there be any benefits to the stock set up compared to running one large Honda throttle body at 70mm or 80mm inlet and one large blade? Ideally you make as much hp per psi you can get

Reason I'm asking is due to my failed iac valve. Thing won't start if its been off for a while. If I hold the throttle at 5-10% it starts right up. Used to work on the ms3 idle output but now it won't open. Maybe just needs cleaned?
 

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Discussion Starter #5 (Edited)
Alright heres all she gots with the stock spec clutch. New clutch on the way. 1/4 mile strip out in Mexico.

Cleaning up the ve table through the rev range gotta get my rpm range moving up. Currently limiter is at 5500 rpm but the head is set up with dual valve springs and the with the cam im going to shoot for 7000 rpm redline to get the most out of the gears.

Need more fuel to support more boost so either water meth or bigger injectors will be the next step for more power.

New clutch on the way, going to throw a new steering rack and struts in it. Weld the pin on the trans and send it at our local drag strip

 

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Discussion Starter #6
Here's the idle currently. Backed fuel off to 12:1 afr roughly. 17 degrees ign advance. 700 rpm idle. Found that it surges when it idles close to stoich. The idle screw is mostly closed. It also surges if I use the idle screw to bring the rpm up past 800. Itll idle at 850 rpms smoothly with afrs in the 11s but that smells terrible. Ill try and back more air and fuel out of the idle together and see what that does for it. Thanks for any input

 

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Discussion Starter #8
Also I didn't realize wot naturally aspirated here at altitude gets me 82 kpa so 140 kpa is around 8 psi here at 6000 ft
 

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Discussion Starter #9
Just tracking my progress. Here's less fuel in the ve table. I've found that my tps enrichment settings were too high and it was overfeeding as the rpms increased. Set the cutoff for tps enrichment at 3500 rpm. These afrs are better under boost.

 

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Discussion Starter #12
Spark cut rev limiter with progressive retard set up right before in the rev range. Progressive retard starts around 5000 pulling 30 degrees total timing , then
spark cut hits at 5500 cutting 4 out of 5 events. Seeing if they can work together

 

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Spark cut rev limiter with progressive retard set up right before in the rev range. Progressive retard starts around 5000 pulling 30 degrees total timing , then
spark cut hits at 5500 cutting 4 out of 5 events. Seeing if they can work together

I'm not sure your RPM cut is working properly, for a fraction of a second your entire RPM bar is lit up and the RPM window reads 7816 RPM.
You mention at 5000rpm your pulling 30* total timing, how many degrees are you pulling at 4500rpm?.

Also I am noticing a speed of 0 MPH, I will assume you are doing this in neutral. From my experience with the F2T running wide opened throttle in neutral can score the oil pump crank seal causing it to leak. This is not a big deal and it's not hard to change on the car (drill a drywall screw into the seal and pull it out, grease the new seal and put it in position, take the old seal and put it backwards against the new seal, pound the new seal in using a piece of pipe or tubing against the old seal.) but it is time consuming.

Have you changed the clutch yet?
 

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Discussion Starter #14 (Edited)
I noticed the rpm spike too im not entirely sure what caused it. That was the first attempt with those rev limiter settings. The progressive retard settings allows a maximum timing retard of 30 degrees when its at a fixed 5000 rpm setting. Its not fast enough to hold the engine at that rpm which then hits the spark cut limiter at 5500. Well its supposed to. It appears it works and the spike is after I lift off. I don't ever really rev it sitting still so thanks for letting me know so I test the limiter while rolling! Tbh dont like drawing too much attention anyways so im not bang popping ever or really even see the limiter much accept when the clutch is slipping. It needs more limiter tuning for sure. The previous spark and fuel cut worked great but not really what im after.

Have not changed the clutch but was testing the fuel system for 12 psi going to turn the base fuel pressure up to 50 to see if the duty cycle can be reduced. I will be doing related maintenance during the clutch swap so waiting for a few parts then going to bang it out one weekend. Opened the wastegate and tested 1/4 mile time and clutch does not spin. Round high 15 seconds low 16. Too slow mainly seeing if the clutch was shot. The clip is of my rolling rev limiter. Launch limiter is at 3500 but thats turned off until i can control my main limiter off the same style as im learning more about rev limiters
 

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Discussion Starter #15
Going to try running just the spark cut limiter by itself. I think i got confused setting up the limiter cause megasquirt allows you to set both up simultaneously which made me think they could be run in conjunction. Maybe they can't? Ill find out
 

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I will verify accuracy on the boost gauge hooked up to the manifold, then put it back before the throttle body, at the same time reinstall the boost controller plumbing in the order you stated. If it indeed is a 2psi drop across that throttle body id say thats fairly restrictive. Nothing a couple more psi can't fix but on a side note, looking at our dual blade throttle body is there any advantages to this or is it more or less an experiment from Mazda and Ford? Are there other cars out there utilizing a dual blade throttle body where one port is smaller than the other? Would there be any benefits to the stock set up compared to running one large Honda throttle body at 70mm or 80mm inlet and one large blade? Ideally you make as much hp per psi you can get

Reason I'm asking is due to my failed iac valve. Thing won't start if its been off for a while. If I hold the throttle at 5-10% it starts right up. Used to work on the ms3 idle output but now it won't open. Maybe just needs cleaned?
The double plates I believe are just to get the surface area with the shape of the manifold inlet. The plates open slightly staggered which helps with low speed driveability. But they changed back to a more normal single plate throttle for the 2gens.
 

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Discussion Starter #17
Cool that makes sense. I was being dumb and didn't realize that up here at 6000 ft we can't get 100 kpa and my kpa to psi conversion was off. Ill end up converting to a large single but for now I'll just start the car with my throttle position at 2% and warm it up with my foot. Works just as good being I don't daily drive it. Can't seem to find these cars in the junkyards out here either.
 
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