mopowers said

Like @Kern Dog and @RBConvert , I'm currently putting together a mild small block. Mine is a 408 roller LA with TF 190 heads that will be 100% street driven and must run on 91 octane pump piss. I just picked up the block from the machinist yesterday. He surfaced the deck, but told me to mock up the pistons and bring it back if I need any more taken off.

In mocking up the corner pistons/rods (1,2,7,8) I came up with the following piston-to-deck clearances (all below deck):

cyl 1: 0.007"
cyl 7: 0.007"
cyl 2: 0.004"
cyl 8: 0.007"

View attachment 1716407854

I already have 521SD gaskets that I've read have a compression thickness of 0.052". Based on my piston-to-deck clearance, that gives me 0.059" quench distance - more than the 0.036" - 0.045" that I've read is ideal. Is that extra 0.014" a deal breaker?

Based on measurements I've taken and several compression ratio calculators, my static compression ratio with that gasket puts me right at 10.0:1 with 7.9 DCR, pretty much right where I wanted - only without any usable quench.

My questions are:

1. Is it worth taking the block back to have zero decked? He'll do it free of charge. That would result in a SCR of 10.17 and a DCR of 8.02. But I'd still only have a quench distance of 0.052".
2. Or... Would I be better off zero-decking and using a thinner gasket to achieve an ideal quench distance? A 0.040" gasket would put the SCR at 10.45, and the DCR at 8.24 - both quite a bit more than I was hoping for.
3. Or... Should I just send it as-is and quit over-thinking it?

I just don't want to worry about the detonation issues at all, which is why I was trying to limit CR to 10:1 w/ the aluminum heads. But for detonation resistance, is it better to have higher compression with good quench, or lower compression with no quench?

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