1958 365 C I engine Q

[Jerry Michaels #21204]

I am going to rebuild the 365 ci in my 58 Eldorado, My question is has anyone ever punched a 365 ci out to a 390 ci? Are the cylinder walls thick enough?? I know about sonar but just wondered if anyone has done it here. Thanks

[Paul Flykt #18899]

I dont think that is possible. You would have bore it 0.130 over to get close to 390. In 59 Cadillac increased the stroke from 3 5/8 to 3 7/8 to get to 390 leaving the bore at 4.0. When I rebuilt my 57 my machinist was a little concerned about going to 0.060 to clean up the cylinders on my block.