Thread: Heads- which is good?

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Using a bore of 4.00", stroke of 3.48", 64 cc heads, 8 cc's in the deck, 8 cc's in the gasket and 7 cc's in the piston crown, I get 9.22:1 for scr. With the KB calculator using 5.7" rods and a cam with an intake closing point of 27* ABDC @ 0.050" tappet lift, I get 8.44:1 dcr. According to everything I've read, somewhere around 8.0:1 is ideal for pump gas, but everyone also seems to think the KB calculator is conservative, so I bump it up a little over 8.0:1 when using the KB. If using a cam with a 30* ABDC closing point @ 0.050" tappet lift, the dcr would be 8.33:1. If using a cam with a closing point of 33*, the dcr is 8.21:1, so somewhere in that area of 27* to 33* should work out. You won't be able to use as much cam as you might think with 9.22:1. Here's an example that would work:
http://www.cranecams.com/?show=brows...tType=camshaft
You haven't said what your piston deck height is, but if the piston is down in the hole very far, I'd use a 0.016" steel shim head gasket to try to get close to the ideal 0.035" to 0.040" squish figure.
http://kb-silvolite.com/calc.php?action=comp2