Edelbrock Performer RPM (7577) and 360 Magnum CI heads

Thanks for the caution. I did check the piston to deck height and the piston is .002" below the deck. The stock pistons were setting .060 below the deck and the calculated CR was around 8.8:1. I went to the KB-107 piston to increase the CR and was aiming for a calculated CR around 9.5:1. I believe that I'm now actually more like 10.5:1, which is a lot more than was expected.