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help cam swap my 04GTO Ls1

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hello any help appreciated new to this gas tunning world, im a diesel mechanic working on my 2004 gto ls1 manual , installed a 227/234 600 111 lsa 109inc cam to have a little more fun , i have supporting mods headers , intake, full 3 inch dual exaust no cats etc, im running stock injectors installed. . can anyone please help me get this thing to idle ,and run somewhat ok.. it starts up but surges once warms up alittle, then bucks and runs real rich from the smell at the tailpipe.

im using hp tuners to read and record data from my car. any help really appreciated.

Attached Files
  • 12-31-21-04-gto-start-up-and-warm-up-after-cam.-1.hpl
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  • 12-31-21-04gto-data-after-cam.hpt
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Hi Juan, I don't have my PC laptop with me right now so can't check out your log or tune. I'll be back next week so can take a better look.

The usual idle problems come from a target idle that's set too low and a failure to properly adjust the base running airflow tables which can be thought of as the starting airflow target for idle control. Your cam isn't massive but will still need the idle to be probably in the 750-800 rpm hot vicinity. This webinar should be of some help - https://www.hpacademy.com/previous-webinars/217-idle-tuning-hp-tuners-gmhp-tuners/

The rich smell is an aspect of the cam operation at idle. If you're running closed loop then the ECU will target lambda 1.00 but due to the unburnt fuel the effective AFR is richer. The only way to get around this is to disable closed loop control and then specifically tune for a lean idle - Perhaps in the 1.10 vicinity. You can really only do this by trial and error and see what sort of target lambda gives the best idle quality.

Hopefully that's of some help until I have a PC in front of me.

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