Hello,
I'm helping my brother tune his 2006 Corvette LS2, which has a Stage 3 Summit Pro LS cam, with supporting parts (stock intake and fuel system). I've gone through guides on idle tuning, but cannot get it figured out. Stopping the idle timing adjustments has no change. The only way I've been able to get it to not surge was by disabling adaptive idle, and bringing down base airflow to ~6g/s which doesn't seem right at all, and even then the idle is around 1000rpm. We've thoroughly checked for any vacuum leaks. Manifold seals have been replaced, and there are no PCV lines to the intake (catch can) - they are all plugged on the manifold. Brake vacuum line is also good. We've even sprayed the whole thing with brake cleaner while running, which had no effect.
All that to say, I think I'm missing something in the tune, here. Any assistance would be appreciated.
The tune is far from complete. Note there is no MAF or closed loop, just using wideband error. It is pretty rich after startup, but goes to normal after a few seconds. Car is also a manual. I have the same cam along with fully built top and bottom end (high compression) in my 2000 C5 and don't have this issue at all.