360 Already Bored .030

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Drg racr

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My '72 360 has already been bored .030, and there's a bit of a ridge in the cylinders. It was rebuilt stock many years ago. Would it be safe to bore it another .010? Bummer is, I already bought a set of .030 over KB191's for it, and I'm concerned putting them in with the ridge there.
 
Probably, but, ansonic check would prove it's worth.
 
Drg racr said:
My '72 360 has already been bored .030, and there's a bit of a ridge in the cylinders. It was rebuilt stock many years ago. Would it be safe to bore it another .010? Bummer is, I already bought a set of .030 over KB191's for it, and I'm concerned putting them in with the ridge there.
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I don't know your situation, I assume the block is thoroughly cleaned, so you can say for sure it is a worn ridge. But I've seen some mopar blocks with what 'appears' to be a hefty ridge is sometimes mostly carbon and gunk.
I don't think they can bore just 0.010", but a good machine shop can machine hone 0.010", of course it has to have sonic Okey dokey, like has been mentioned.
 
Had a early 360 block just bored from .030 to .040 just a couple of month ago.....

Got a early 360 block that is .060 that was in service for 10 yrs....thinking about going .070 over...
 
suppose to be...but i would not invest any money in a .060 block unless I sonic test it....
 
For a mild to modest build most of the LA small blocks will go .060" no problem. The 400 ish hp '68 340 in my Duster is .060" over, no issues with it at all. Smart money is what 70aarcuda said though, have a sonic test done. Especially if it's going to be a higher horsepower engine, no point buying high dollar parts for something that could end up a boat anchor. Lots of blocks wouldn't have an issue, but there are core shifted examples running around out there that won't take a .060" bore without being too thin. Only way to know for sure is to sonic test it.

As for the later blocks are thinner thing, there are more than a few folks out there that don't believe that. The folks at 440 source are one of them. Now that's for big blocks of course, but they say it's bunk. 440 Source.com Everything you've ever wanted to know about blocks and more....
 
supposedly, the early 360 blocks were cast with 340 cores that were made for 4.04 off the bat so a +.040 may be just starting life.
 
pishta said:
supposedly, the early 360 blocks were cast with 340 cores that were made for 4.04 off the bat so a +.040 may be just starting life.
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I have heard that, but I haven't seen one in person. I believe the ones that were allegedly on 340 cores were cast in 1970 for the '71 model year though, anything much later than that would have been on a 360 casting. I don't think the OP's '72 cast engine would be like that.
 
71-73 all have the same casting number...and with the end of production of the 340 in 1973....I would GUESS...that is went the 360 casting changed...as did the casting number...Just old wives tales...
 
winstoninwisc said:
it'll go .010 more
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I`d have it taken out to .040 and not worry about it at all !!!!!!!!!!!!!!!!!!trade pistons w/ the above poster if his is the kind u want. If not, exchange the pistons w/ whom ever u bought them from maybe.
 
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