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dz1087 · 07-12-2022, 04:20 PM

Back on this subject now:

Looking at a photo of my pistons, they are flat top, 7cc valve relief pistons. And they are some unknown distance in the hole. I'm assuming .020-.025 as I did not ask the machinist to deck the block, just square it up.

I'll definitely check the piston clearance when I pull the heads, but now I'm curious about compression. If I go with a 64cc head and a .015 gasket, I'm calculating 10.27 : 1 compression.

Is 10.27 streetable? Seems a little high. Any benefit with going aluminum to handle the increased compression on a street truck?

07-12-2022, 04:20 PM	#15
dz1087 Registered User Join Date: Feb 2019 Location: Navarre, Florida Posts: 199	Re: 355 Build Back on this subject now: Looking at a photo of my pistons, they are flat top, 7cc valve relief pistons. And they are some unknown distance in the hole. I'm assuming .020-.025 as I did not ask the machinist to deck the block, just square it up. I'll definitely check the piston clearance when I pull the heads, but now I'm curious about compression. If I go with a 64cc head and a .015 gasket, I'm calculating 10.27 : 1 compression. Is 10.27 streetable? Seems a little high. Any benefit with going aluminum to handle the increased compression on a street truck?