The Scat kit I am getting comes with KB745 forged step dish pistons:
http://kb-silvolite.com/forged.php?action=details&P_id=325If you run them with open chamber J heads your compression will be about 9.4-9.5 to 1 which will work good for pump gas. Get the block machined so the quench pad is at zero deck and the dish portion is below deck. Then later you could switch to Edelbrock closed chamber heads for 10:1 compression pump gas motor.
Like Harms said, if the budget is tight put the money in the short block so that high flow closed chamber heads can be put on later when more funds become available.
