Fidanza flywheel question

[Rocketst]

So I've been on the hunt for the answer to my misfires for about 4 months now and it's leading me to the tranny. Does anyone have a fidanza flywheel and can verify whether or not on decel you guys are getting massive misfires? This seems to be a problem in the sti community and I was wondering if it could hint to my misfire problem as well. Misfires usually happen upon letting off gas then easing back on, high revs around 4k and sustaining them and decelerating via downshifting or decel then easing on gas. I'm also wondering what parameter in the tune has to be edited. I am thinking that the stock ecu is seeing the decel happen differently then the stock car so it shows it misfiring when it actually isnt.

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[Fusion Works]

No issues on my car. I get no misfires, (although I am not monitoring those, but have no CELs).

 

[Rocketst]

Thanks for the response.

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[Fusion Works]

Do you want me to monitor misfires and see if I can replicate your issue?

From what I understand the Subaru issue comes from the rate of change for rpm. Something about the ECU expecting to see a certain RPM rate of return. The steel flywheel of course meets what Suby programmed for at the OE calibration. The aluminum flywheel obviously allows that to return to zero faster. Then the ECU has an overshoot situation. Maybe I am wrong, I'm not a Suby Tuner.

 

[Rocketst]

Could you please? That would be really helpful. I've stated in other posts I usually notice it when I let off the throttle and then ease back on it.

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[Rocketst]

I doubt your gonna have the same problem as me but I get rapid misfires at 4k when I let off the throttle down to maybe 5%? But I think that's an issue me and Alex are gonna have to work through and a characteristic of the motor not the flywheel

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[Rocketst]

The misfires that I'm getting when I ease back on throttle seems like it misses on all 4 cyl then corrects itself but this is different then the high rev misses and I can't actually feel them

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[Fusion Works]

I'll switch that on to log in the morning and see how she does for a couple of days.

 

[Fusion Works]

Some initial testing, I am showing about 10 misfires in 30 minutes of driving. 1/3 appear to occur at cold startup/warmup. Can't recreate a situation like you are seeing. I can chip throttle at 4K and see no real change in misfires. How many misfires are you seeing.

Looks like I am getting almost -2/+6deg of igntion correction and one or two knock counts in the same drive.

 

[Rocketst]

Yeah yours I would consider normal. The worst I've gotten is 1634 over a 30 min drive to work lol

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[Rocketst]

Lately though it's gotten a lot better. Alex has been working really hard to figure out why it's missing and I think he's close to figuring it out. With tuning he's gotten it down to 500 in the morning drive to work (I think it's due to it being colder out) and 900 on the way home in 90-100 degree weather.

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[Rocketst]

Based off your test run and the number I dont think my flywheel is causing them. Thank you for your help.

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[Fusion Works]

You are welcome. Good luck solving it.