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Common Pontiac Displacements and Overbore Displacements.


inches metric
bore 4"
stroke 3"
overbore 0 0
disp/cyl 37.6911 cid 617.77 cc's
displacement 301.59 4.942 liters
new bore size 4

301 bored .030 over

inches metric
bore 4
stroke 3
overbore 0.030
disp/cyl 38.262 cid 621.43 cc's
displacement 306.13 4.91litres
new bore size 4.03

301 bored .060" over

inches metric
bore 4
stroke 3
overbore 0.060
disp/cyl 38.83 625.09 cc's
displacement 310.71 5.0 liters
new bore size 4.06


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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