[1FastSTi]

Anyone who has any tuning experience will be able to see in my log that my ECU is pulling timing hurting my HP output. You can see from 5075 rpms to 5714 rpms the ECU has the advanced timing knocked down to 1.5 when full advance would be around 5 degrees on top of a primary ignition of approx 15 degrees. You can also see in the log there is no sign of knock at any time. We stopped tuning when we couldnt get anymore timing out of the engine. We had also come to the conclusion that this was probally caused from terrible Hess 93 gas.

Any input would be apprieciated.

Brian

http://www.prizer-painter.com/person...0208195548.csv

[STirish]

Originally Posted by 1FastSTi

Anyone who has any tuning experience will be able to see in my log that my ECU is pulling timing hurting my HP output. You can see from 5075 rpms to 5714 rpms the ECU has the advanced timing knocked down to 1.5 when full advance would be around 5 degrees on top of a primary ignition of approx 15 degrees. You can also see in the log there is no sign of knock at any time. We stopped tuning when we couldnt get anymore timing out of the engine. We had also come to the conclusion that this was probally caused from terrible Hess 93 gas.

Any input would be apprieciated.

Brian

http://www.prizer-painter.com/person...0208195548.csv

There does not need to be "registered" knock to bring the advanced multiplier down. I don't know if this is a factor, but your AVCS angles are dropping off pretty drastically right where your timing is dropping. You can also see the air flow dip at that point too.

I wouldn't leave timing on the ragged edge, pull it back a few degrees. Unless you are heat soaked(Yes, I see you have a FMIC), I would think you should be able to run more timing than you currently are though. Are you making sure that your IATs and ECTs are in check before every run? I've never tuned a SZ55 to say anything for sure.

[1FastSTi]

Originally Posted by STirish

There does not need to be "registered" knock to bring the advanced multiplier down. I don't know if this is a factor, but your AVCS angles are dropping off pretty drastically right where your timing is dropping. You can also see the air flow dip at that point too.

I wouldn't leave timing on the ragged edge, pull it back a few degrees. Unless you are heat soaked(Yes, I see you have a FMIC), I would think you should be able to run more timing than you currently are though. Are you making sure that your IATs and ECTs are in check before every run? I've never tuned a SZ55 to say anything for sure.

Thanks for your input. The car was allowed to cool after each run for about 10 minutes. The shop where the tuning was done at was probally about 45 degrees inside. Do I need to manually adjust the advance muliplier? It was left alone at 0.5. Here is the dyno chart from some of the runs we were doing. You can see how it the engine almost starts breaking up in the upper RPMs Does anyone feel at all this could be caused from poor fuel?

[jays05]

I have a couple comments...

1) You can default your IAM to 1.0 in StreetTuner, I suggest you do this, but if your car was tuned with the IAM set to 0.5 you're going to have a lot more timing and may need a re-tune. Having IAM default to 1.0 is nice for resetting the ECU at the track and stuff like that.

2) The "Knock Activity" field in StreetTuner logs will only show knock if the car is knocking at the exact polling interval of StreetTuner. It isn't like UTEC or anything like that. You can have knock and it may not show up in the logs.

3) What have you tried doing to fix the issue between 5000-5700? Have you tried tapering boost a little bit thru that region? Is is really interesting, as pointed out already, that it starts pulling timing when the ACVS angles back off. Have you compared your logs to your ECU maps?

[1FastSTi]

Originally Posted by jaygoesfast

I have a couple comments...

1) You can default your IAM to 1.0 in StreetTuner, I suggest you do this, but if your car was tuned with the IAM set to 0.5 you're going to have a lot more timing and may need a re-tune. Having IAM default to 1.0 is nice for resetting the ECU at the track and stuff like that.

2) The "Knock Activity" field in StreetTuner logs will only show knock if the car is knocking at the exact polling interval of StreetTuner. It isn't like UTEC or anything like that. You can have knock and it may not show up in the logs.

3) What have you tried doing to fix the issue between 5000-5700? Have you tried tapering boost a little bit thru that region? Is is really interesting, as pointed out already, that it starts pulling timing when the ACVS angles back off. Have you compared your logs to your ECU maps?

To be honest with you we tried just about everything to get the timing we wanted to run. I really need to do another pull and log that so I can see whats going on at this very instant. At the end of the tuning we were messing with the cam timing to see if there would be any effect, cam timing had no effect on it. My tuner is very expeienced with STi's and said he has never seen such a thing before. Making us think the only real possibility could be the fuel.

[1FastSTi]

I did more logging tonight with a fresh tank of SUNOCO 93. I almost immediately received full advance. Back to the dyno for more tuning!!! Remember DONT BUY HESS GAS!!!!!

[mofoSTI]

I have had this issue before right before an auto-X. I had to run out my gass throw some booster and a few gallons of 92 oct. After that it was all good on the tuner.