i build every engine for the use it will see like blower. turbo .Nos. class of racing . and were the budget is along with that machine work or added work to parts as well for them to live longer added to this there is RPM range were it works the best at . i can not help on summit heads i do not buy parts from them or heads you need to work up your build. to work out the port runner and chamber size like dave said.but the RHS heads that is a vortec replacement head is a good head to start with