I have a fresh build lm7 based engine. I have changed usual parameters for a cam swap but am having issues with idling still and have lack of idle control in my scanner when the engine is running too.
Engine is stock LM7 with exceptions of Summit 8706 stage 2 turbo cam, flat top pistons, and dual valve springs.
Cam Specs:
Summit Racing SUM-8706: Stage 2 Pro LS Turbo Cam. 226/230 Dur., 113+4, .600/.575 Lift, 3-bolt, 5.3, 5.7, 6.0, 6.2, 7.0, Vortec Truck, LS1 LS2 LS6 LS3 LS7 LQ4 LQ9 LS9, Each
This motor is in my crawler with a th400 and np205 behind it with 4.56 gearing. At this time, the motor will idle for a short amount of time and needs throttle to start. Only other issue I am having is slightly lower fuel pressure at 55psi, but that will be fixed soon.
At this point I have done a typical change to target idle tables and airflow tables; however, I did notice that at some points it will idle on its own without slight throttle , but does surge still. I am not sure if the compression increase is also causing problems to typical changes for cam tuning. Also, I do not have a wideband at the moment, but this rig does not see high miles and is typically slow moving or wide open. Jeep 1.hplJeep 1.hpl