Author Topic: affects of decrease combustion chamber by 6cc  (Read 3459 times)

Offline Todd440

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Re: affects of decrease combustion chamber by 6cc
« Reply #15 on: December 17, 2015 - 08:40:15 PM »
Sorry about that!  I was using the iPad, and couldn't find the proper symbols.  Once you do it a few times, you can do it on a calculator in less than 30 seconds. 
So, if you have a flat top KB, probably the 237 piston , and zero deck, you'd be 10.32  to 1 with 84cc heads, and 10.92 with the 78cc TF heads.  That's assuming you have a composite head gasket at .039 thick, which most are. 
Also, never assume the advertised CC's of products.  You'll find they are all over the board. 




Offline GreenFish

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Re: affects of decrease combustion chamber by 6cc
« Reply #16 on: December 18, 2015 - 12:12:46 PM »
Sorry about that!  I was using the iPad, and couldn't find the proper symbols.  Once you do it a few times, you can do it on a calculator in less than 30 seconds. 
So, if you have a flat top KB, probably the 237 piston , and zero deck, you'd be 10.32  to 1 with 84cc heads, and 10.92 with the 78cc TF heads.  That's assuming you have a composite head gasket at .039 thick, which most are. 
Also, never assume the advertised CC's of products.  You'll find they are all over the board.

 :cheers:  Thanks man, That's about what I was thinking in my head. Not that big of a difference. I could even go with a thicker head gasket if 10.92 is too high i suppose.
70 cuda, 440, KB pistons, 10.5:1 compression, edlebrock heads,RacerBrown cam, 5-Speed Tremec, Megasquirt EFI

Offline Chryco Psycho

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Re: affects of decrease combustion chamber by 6cc
« Reply #17 on: December 18, 2015 - 12:46:18 PM »
Quench is more important than compression so stay with .040 gaskets [ I would use Cometic with alum heads ] & 10.9 compression should work great

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Offline GreenFish

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Re: affects of decrease combustion chamber by 6cc
« Reply #18 on: December 20, 2015 - 10:36:42 AM »
Quench is more important than compression so stay with .040 gaskets [ I would use Cometic with alum heads ] & 10.9 compression should work great

Cool, thanks
70 cuda, 440, KB pistons, 10.5:1 compression, edlebrock heads,RacerBrown cam, 5-Speed Tremec, Megasquirt EFI