As the title says...can a set of 72cc heads be safely milled down to 64cc?


Also, my 355 is supposed to havea SCR of 10.5:1 w/ 64cc chambers, what would it be if i left the heads un-milled with 72cc chambers?


I have a chance to pick up a set of 72cc Trick Flow 23 degree 195cc heads but they're 72cc. Id prefer NOT to have to mill them, but if they're going to drop the compression drastically im not going to like that.

Suggestions?

 

You can't mill them down that far, without having to resort to angle milling or something, and then you'd be milling the intake, etc etc.
Give me all the specs for your shortblock. I doubt you have 10.5:1 with 64cc chambers anyway.
What pistons, deck height, etc?

 

The short block has Hyperutectic flat-tops with 2 valve-reliefs per cylinder. I dont know all the exact details, but the guy i got the short block off of told me be built it for 10.5:1 compression for his 64cc double hump heads.

I know the 355 w/ the double humps and a Lunati Bracket Master II cam, did 12.4 @ 111mph in his 3200lb car (without driver) with an auto and stall, all motor.

Assuming it actually is 10.5:1 compression, what would 72cc chanber heads drop the SCR too?

 

We can assume it would be 10.5:1 compression, but that's not really all that possible/probably.... Are the heads on it now? If not, then measure the deck height and find out.

Realistically you have about 9.3:1 right now. If the guy really knows his stuff (zero decked it), then 10.3:1. I can't figure 10.5:1 (and zero decking isn't all that common )

However if it does have 10.3 then the 72 cc heads would drop it to 9.4:1 (assume zero decked, rebuilder gasket, 5cc reliefs)