jeepthrills01
Well-Known Member
I read an almost 20 year old post where a very respectable member of another board said,
"1968 and 1969 383 2&4 bbl pistons shared the same Compression height...just the 2bbl were dished."
With more info available these days as our world continues to grow smaller, would anyone care to add yes or no to that statement? Yes 2 bbl were dished...most of us agree on that...but the same CH?
My reason for the inquiry pertains to my own low..LOW LOW buck 383.If your not familiar...i acquired said engine in a completely rebuilt state...it had just been sitting for 20 years wrapped up in a Phoenix garage. No surface rust...gobs of engine lube on the cam....and very inexpensive.
These dished 2 bbl pistons measure .007 below deck at the four cardinal points for all 8 cylinders...yes..32 separate measurements..all equal. And 8 center of piston depth measurements of .09
The 12cc dish is keeping me just below the 9s on CR (8.88) . Block was very carefully decked...im assuming .015 as my research states most OEM 2bbl pistons living .020 to .030 in the hole.
I already have Eddy 82cc heads, a mild Voodoo [email protected], .475 .484 cam, 1.6 rockers and 1.75 headers.
But cracking 9.7 or higher and getting some quench seems plausible with flat tops considering where the pistons currently sit. It could make the difference of a runner..or a screamer.
I know were talking about a bump of 1.1-1.6 in CR which is what..15 hp?..but the possibility of quench and efficiency (as opposed to race gas and spark knock) intrigues me.
This engines purpose would be 70-80% street...with monthly trips to the run what ya brung at the local strip.
Slap it together as is? Find pistons?
Low Buck Thoughts?
"1968 and 1969 383 2&4 bbl pistons shared the same Compression height...just the 2bbl were dished."
With more info available these days as our world continues to grow smaller, would anyone care to add yes or no to that statement? Yes 2 bbl were dished...most of us agree on that...but the same CH?
My reason for the inquiry pertains to my own low..LOW LOW buck 383.If your not familiar...i acquired said engine in a completely rebuilt state...it had just been sitting for 20 years wrapped up in a Phoenix garage. No surface rust...gobs of engine lube on the cam....and very inexpensive.
These dished 2 bbl pistons measure .007 below deck at the four cardinal points for all 8 cylinders...yes..32 separate measurements..all equal. And 8 center of piston depth measurements of .09
The 12cc dish is keeping me just below the 9s on CR (8.88) . Block was very carefully decked...im assuming .015 as my research states most OEM 2bbl pistons living .020 to .030 in the hole.
I already have Eddy 82cc heads, a mild Voodoo [email protected], .475 .484 cam, 1.6 rockers and 1.75 headers.
But cracking 9.7 or higher and getting some quench seems plausible with flat tops considering where the pistons currently sit. It could make the difference of a runner..or a screamer.
I know were talking about a bump of 1.1-1.6 in CR which is what..15 hp?..but the possibility of quench and efficiency (as opposed to race gas and spark knock) intrigues me.
This engines purpose would be 70-80% street...with monthly trips to the run what ya brung at the local strip.
Slap it together as is? Find pistons?
Low Buck Thoughts?
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