Custom OS went screwy?

[slowhawk]

Have a custom OS setup in my buddies 00 Camaro-6sp.It is running an 02 calibration in SD and has been running great.It was tuned before this way,everything was great and made 440hp. Added a FAST 90mm setup and street tuned it,still great.

Went to the Dyno and the timing would go to the minimum set (16 degree's,435hp)whenever we go WOT .When I fully tuned it on the street it would always hit the commanded timing of 28 degree's. I tried messing with a bunch of stuff but nothing helped.Ran out of time so I didn't go back on the street.

Any idea's of what to look for? Car is not throwing any codes.

Thanks

[TAQuickness]

to eliminate a COS, did you try putting an OEM tune back in?

You could also try comparing the current tune to the last known good one.

[GMPX]

Is it possible with the slightly different combo now, on the dyno you were hitting some areas in the tune that you didn't see on the street?

Cheers,
Ross

[slowhawk]

This tune was the same one we tuned on the street where it had the 28 degree's at WOT.I've made no changes since.Going back to stock will be a bitch since we redid the whole intake setup.I have a few more things to try.

[Tordne]

Going stock again isn't too bad. You can use your Custom OS as a cal flash into the stock OS . Then just change/check those tables that were modified in the Custom OS (i.e B3647 etc.).

[Scoota]

Having the car surrounded by four walls and a roof will always have some sort of effect on the tune; i.e. Humidity is always slightly lower inside a shop than outside and with engine bay temps higher, we usually have an opposite effect to what you are experiencing.

You would be amazed at how much timing needs to be pulled from the tune when road testing the vehicle because of the four wall climate change.

Do you have a log from when it was on the Dyno? Could it be your air temps pulling timing?

Cheers Scotty.