Compression Ratio
03-14-2006, 03:41 PM
#12
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The cam company can provide that for you. You can get the valve events if you know the ICL the LSA and the duration and how you want it timed with the crank. I'll calculate that too if you want. 
I'm a junky when it comes to building engines on paper.
I'm a junky when it comes to building engines on paper.
03-14-2006, 04:18 PM
#13
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Well in a 408 with a 6.125" rod a 4.060 gasket bore, a .035" gasket, a 76cc combustion chamber, a 7.5cc piston dome that puts you at about 12:1 SCR.
You'll need a cam with an IC point of about 66* ABDC at .050" lift to get your DCR down to 9.5:1. Translation: Big *** cam
You'll need a cam with an IC point of about 66* ABDC at .050" lift to get your DCR down to 9.5:1. Translation: Big *** cam
03-14-2006, 07:27 PM
#15
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OKay ... you're dead on the 408, but you missed some details.
Heads will be 72cc, gasket will be .030, and the piston will be -2.
ORRRR
Heads will be 66cc, gasket .040, and -2 pistons.
The idea with the first setup is that I can change pistons and head gaskets at a later date and drop the CR a good bit for some positive manifold pressure.
Heads will be 72cc, gasket will be .030, and the piston will be -2.
ORRRR
Heads will be 66cc, gasket .040, and -2 pistons.
The idea with the first setup is that I can change pistons and head gaskets at a later date and drop the CR a good bit for some positive manifold pressure.
