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Old 08-31-2012, 10:30 AM
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Here just use a calculator:
Expert Advice - Expert Advice -

You divide the volume of the cylinder at BDC by the volume at TDC.

Combustion Chamber Volume In CCs = 58 cc (stock 416 heads specs, unsure if large valves will affect that?)
Large valves will not effect that. Generally factory cast heads are going to be larger than advertised. So unless you actually remove the heads and CC the chambers yourself, you might want to run calculation on the high side, some where in the neighborhood of 60-62cc.

Piston Dome Volume In CCs Negative For Dished Pistons (Use '-') = ??
Enter Piston Deck Clearance Negative If ABOVE Deck (Use '-') = ??
*There are flattop pistons=0cc
*There are flattops with 2 valve reliefs, approx +2 to +4cc
*There are flattops with 4 valve reliefs, approx +5 to +7cc (this would be used in a typical performance rebuild)
*There are dished pistons (concave on top). Dished pistons would be like +9cc to +18cc. (this would be a typical untouched factory engine).
*There are also D-dished pistons, which are flat on one side and deep dished on the combustion chamber side. These would be like +9 or more cc's.
*There domed pistons, which are convex on the top, thus taking up space out of the cylinder, so these are NEGATIVE cc's. Typical values would be like -5cc to -15cc.

Deck clearance is measured from the top of the block to the top of the piston (edge of the piston, not the center where the dome/dish is). An untouched factory block would have .025" deck clearance. If the block has been decked, then this value would be smaller.

Last edited by Silver Surfer; 08-31-2012 at 10:40 AM. Reason: more info added
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