You should have a ground cable from the alternator housing or mounting bolt to the battery negative on these units, that might be the problem. I generally don't recommend grounding them through the mounting blocks.

Your idle speed sounds like it's below the turn-on of the unit, get me the crank pulley size and the alternator pulley size and we can see where we can go from there.

Eric

Sorry ringing in late. Back when I was installing mine I called to ask where I should run the 1/0 ground stud from alt to the car. Matt told me directly to negative of battery was best. It wouldn't hurt cleaning up your ground locations but like Eric said a lot of car models are new to the HO alt scene and there will be "growing pains"

Measure your crankshaft pulley diameter and have patience. It will pay off.

Edited August 2, 201114 yr by crunkjuice1