bar,
Now, I might get some grief about this, but has anyone here actually had a problem with a .060" over bore on a 400 that they can swear was caused by the fact that the block was bored .060" ?? I dont want to hear about the overheating, I think that is bull. If its overheating, its because it is making a lot more power than the cooling system is designed for, not because it is .060 oversize.
Just my opinion,
Merry Christmas to all
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I have seen 2 400 blocks that failed @ .040..both busted cylinder walls out. One was a 5.7 rod/11:1 bracket engine with a fair many passes on it, no NOS or alky, the other a 6" rod 12:1 circle track engine (on alky, the tune up could have caused it so I guess that one is a toss up). These were both "511" blocks.
Seen one "509" block that was .060, 13:1, on alky, bracket engine...lived a long happy life with a "half fill". After four seasons it finally cracked a wall..but it was four long, hard, high RPM seasons that would have gotten the best of nearly anything. I've used a couple .040 "509" blocks that lived just fine.
And no, it's not that bad to hone a .030 block out to .040, but it is a little time consuming, and hard on honing stone sets..most machinists won't fool with it simply because there's more money to be made in less time fooling with something else.