Thread: Boring a 425, how large can we go

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As some of you know I have 1979 425 that was rebuilt and bored 40 over. I sent it & my project truck to a shop be installed & assembled. Now I have a $5000 paper weight because the engine/trans & frame was outside improperly covered when it rained, got water in the cylinders and rusted 3 of them pretty bad. How large can a 425 be bored out??? I thought I had read somewhere they could be taken to 100-125 over. But I could be mistaken. The machine shop said it would machine the 3 worse cylinders to see if they can go 60 over. If not he'd have to take it to 80 over if it could be bored that big. Can the 425 be bored out to 80 over?? And if so is there any negatives, like running hot or any other things.. If its throwing good money away I need to know so I can find another block for the rest of the parts in it. The ONLY reason I am trying to save this engine is it was a Father's Day gift to me from my son the year he joined the Marines about 12yrs ago before it was rebuilt.