What I have is a 440 stroker -.008 in the hole flat top, icon pistions 828 .045 head gasket crushed thickness which would give me .053 quench .What I'm wondering is this too much quench or should I switch to a thinner gasket felpro 1009 which is .039 thick ?The heads are 86cc which will give me 11 to 1 and these are iron heads . My goal is to try run 93 octane .
jim

It's my understanding that with the thicker head gasket you've decribed, you will be just beyond the boundries of effective quench.... With the thinner gasket, you will be at an acceptable quench, but with iron heads, your ability to tune for 93 octane fuel will be wholey dependent upon you camshaft selection.

If this were me ...I would go in and HOG-OUT the combustion chambers ...and then use the thinner gaskets.

I would go with the thinner gaskets. You would probably get some benefit as is, but below 50 is better. Gaskets are easy! I just saw the 11-1 part, good luck! you may want to dish the pistons on the valve side, or some deep valve reliefs.

Let me throw another QUENCH Q in here .... is the best-quench-spec the same on a lower and higher RPM motor?

I have a motor sloooowly going together for that motorhome. The 413 heads have something like low 90's CC combustion chamber spec(closed chamber) .. I was thinking maybe a zero deck with a .019 gasket with a mildly hogged-out combustion chamber to a low 100cc spec.

With so much quench ...I would also think that this would enhance the swirl-effect. But is .019 tooo small on a lower rpm motor?