Jason,
With those pistons at .020 below deck and 77 cc early chambers your C/R is about 9.2 to 1. The TRW / Sealed power pistons have a short compression height and always sit down the hole some at TDC unless the block is decked.
If you set the pistons you have at "0" deck by decking the block and then go to a 72 cc chamber your static C/R will be just shy of 10 to 1 which is fine for your application and power requirements.
I have been doing some reading that suggests that the differences between an iron and aluminum head at the same c/r with identical ports are minimal so do not concern yourself with that aspect.
Large valve ported early castings with a comp XE274H, rpm intake, 750 carb, recurved dizzy and headers will get you 475 to 500 HP pretty easily. The combo will run on pump gas all day long with iron heads and might run with 89 to 90 octane with aluminum heads.
This way instead of buying new pistons you would only need to disassemble your short block and have the block decked enough to bring the pistons a few thousenths above deck. You would be out some time and about $125.00 or so for the decking plus gaskets etc.
Hope this helps some...
:mrgreen:
With those pistons at .020 below deck and 77 cc early chambers your C/R is about 9.2 to 1. The TRW / Sealed power pistons have a short compression height and always sit down the hole some at TDC unless the block is decked.
If you set the pistons you have at "0" deck by decking the block and then go to a 72 cc chamber your static C/R will be just shy of 10 to 1 which is fine for your application and power requirements.
I have been doing some reading that suggests that the differences between an iron and aluminum head at the same c/r with identical ports are minimal so do not concern yourself with that aspect.
Large valve ported early castings with a comp XE274H, rpm intake, 750 carb, recurved dizzy and headers will get you 475 to 500 HP pretty easily. The combo will run on pump gas all day long with iron heads and might run with 89 to 90 octane with aluminum heads.
This way instead of buying new pistons you would only need to disassemble your short block and have the block decked enough to bring the pistons a few thousenths above deck. You would be out some time and about $125.00 or so for the decking plus gaskets etc.
Hope this helps some...
:mrgreen:
