View single post by Judson Manning
 Posted: 08-11-2006 07:01 pm
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Judson Manning



Joined: 03-14-2005
Location: Atlanta, Georgia USA
Posts: 406
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 Use Delta's off-the-shelf JE Flat-top pistons....As you can see below, the pistons can produce a CR range anywhere from  9.5 to 11.5 to 1.

 

A 0.030" over-bore = 502cc/cylinder

Combustion Chamber volume = 35cc to 40cc (depending on amount of shaving)

Delta's Flat-top 'dish' volume = 8.5cc

Head-gasket (new) volume = 9cc

CR = [502 + (37.5+8.5+9)]/(37.5+8.5+9) = 10:1

use OEM or Aftermarket copper gasket (0.030" thick) => CR = 10.7:1

Deck the head and/or Block an additional 0.020" => CR = 11.5:1