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Common Pontiac Displacements and Overbore Displacements.


inches metric
bore 4.1522"
stroke 4.21"
overbore 0 0
disp/cyl 57 cid 934.178 cc's
displacement 456.06 7.473 liters
new bore size N/A

455 bored .030 over

inches metric
bore 4.1512"
stroke 4.21"
overbore 0.030
disp/cyl 57.83 cid 939.5 cc's
displacement 462.67 7.52 liters
new bore size 4.1822"

455 bored .060" over

inches metric
bore 4.1512"
stroke 4.21
overbore 0.060
disp/cyl 58.67 cid 944.84 cc's
displacement 469.33 cid 7.558 liters
new bore size 4.2122"

Back to See other Engine Specs


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