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kootenaycat
01-23-2005, 07:24 PM
Got a question regarding SBC pistons. I just pulled a set of heads off one of the many blocks I have scrounged the past couple years, and was surprised to see none stock pistons! Has anyone used domed pistons before, and any idea what these ones might equal in regards to comp ratio? Of course comp ratio changes with heads and combustion chambers, but assuming 76cc heads, which are common, I'm curious what these pistons would produce.

Also, the heads I pulled have common 1.94 intakes and 1.50 exhausts, but the stems on the exhausts are 3/8" (.371" to be exact) which are the same as a big block 454! Are these valves aftermarket, or do the 454's come with 1.5" exhaust valves? The exhaust guides have been changed to .371", but the intakes are brass inserts at stock diameter (.341).

Stock piston
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Domed piston


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http://www.funinbc.com/forum/uploaded/kootenaycat/200512412335_domedpiston.jpg
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78bronco
01-23-2005, 08:05 PM
I think some where around 9.5-10.1

http://img.photobucket.com/albums/v630/1978bronco/382780_9222.jpg