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Common Pontiac Displacements and Overbore Displacements.


inches metric
bore 4.1212"
stroke 3.75"
overbore 0 0
disp/cyl 50.023 cid 819.72 cc's
displacement 400.18 6.557 litres
new bore size N/A

400 bored .030 over

inches metric
bore 4.1212"
stroke 3.75"
overbore 0.030
disp/cyl 50.75 cid 824.43 cc's
displacement 406.03 6.595 litres
new bore size 4.1512"

400 bored .060" over

inches metric
bore 4.1212"
stroke 3.75
overbore 0.060
disp/cyl 51.49 cid 829.15 cc's
displacement 411.92 cid 6.633 litres
new bore size 4.1812"

Comments and Suggestions

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Feel free to drop me a note. * I am looking for some good articles for the third and fourth gen birds. If you have any that you would like to see on this site send them to me and I will post them on my site.     

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