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A/C question


Well-known member
I have an old 4 cylinder cont. GPU pe 90 with the 470 cylinders on it. It needs to be rebuilt so I pulled off one cylinder. I here you can put 520 cylinder heads on them but when I measured it, the O.D. of the cylinder was 5.187. And if I was told correctly, the 520 piston is 5.25". So do you have to machine out the block to fit the 520 cylinder?
Correct, the only thing thbat you have to do is machine the case out for the larger cylinder, everything else will swap right over.