Low rpm stumble...Have Tunercat

Hey,

New 94 Z28 owner here. 6-speed. My main mods are a HOTCAM kit and LT headers. I have been working on my tune with Tunercat, and I am having severe drivability problems at low, 800-1500, rpms. I have gotten my BLM's straight with VE Master and that has helped a little.

I really have to slip the clutch to get a smooth launch, and it is really easy to stall unless I rev to at least 1800 to take off.

Traffic jams are a real pain. The car bucks badly when in first between 800-1300 rpms.

Until now I have tired increasing timing in that rpm range, that was no help. Do you think that pulling timing would help, or what else can I try?

Thanks

Hey,

New 94 Z28 owner here. 6-speed. My main mods are a HOTCAM kit and LT headers. I have been working on my tune with Tunercat, and I am having severe drivability problems at low, 800-1500, rpms. I have gotten my BLM's straight with VE Master and that has helped a little.

I really have to slip the clutch to get a smooth launch, and it is really easy to stall unless I rev to at least 1800 to take off.

Traffic jams are a real pain. The car bucks badly when in first between 800-1300 rpms.

Until now I have tired increasing timing in that rpm range, that was no help. Do you think that pulling timing would help, or what else can I try?

Thanks

Does it stubble when cold and warm or just when it's not at operating temp?

It wouldnt hurt to try and pull timing.

I thought that sort of behavior was normal with a hotcam.

It bucks and jerks at all operating temps.

Have you logged scan with Datamaster and looked at BLM's. You may have to tweek the MAF table to get low rpm BLM's in check. However, a hot cam is pretty mild, I'm surprised your having problems with mostly stock tables. Might want to verify good plug wires, Coil wire, Opti, etc. My guess is you have problems other than your tune.

Steve