This is and old thread. But I have this engine in my AMX . It has gone a best of 6.08 @ 112 mph. With a small tube header. I'm getting a set of 1 7/8 headers made for it this week and changing the hood so that I can put a spacer on it. The car weighs 2885 with my son in it. I believe it'll go 5.90's @ 114 with the better headers and a carb spacer. BTW this is on Renegade RM 109. I have an alcohol set up I'm going to try at some point.