The heads have been ported and have 2.25-1.88 valves. It has a 5.57 gear and a 4000 stall converter shifting at 6200. It is a basic good street engine and I ran it 12 passes and it went 7.09 first pass foot break and 6.95 2nd pass leaving at 3200. I pulled the 2 step chip out and left on the converter and it went 6.93 4 passes in a row!!!!!!!