The Body Shop TECH General questions that don't fit in any other forum

          
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Old 02-27-2026, 04:46 AM
LM93 LM93 is offline
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Default Is this block junk with these cracks?

My Pontiac engine block got magnaflux'ed at the machine shop and they found these cracks between coolant holes. The yellow lines are powder. It's a small local shop so weld repairing isn't something they offer. I'd have to find somewhere else to send it to, or learn how to drill and stitch myself(not impossible, I've used power tools for years). It's just a basic 350 so I'm not trying to save a 455SD or anything.
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Old 02-27-2026, 09:47 AM
LM93 LM93 is offline
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The thin yellow lines between the yellow paint pen marks are powder, I mean. The shop left it on the cracks to show me them.

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Old 02-27-2026, 09:54 AM
78w72 78w72 is offline
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Probably get better replies not in the body shop section... try street or race.

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Old 02-27-2026, 11:38 AM
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srmmmm srmmmm is offline
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The cracks in that location will prevent the head bolt from maintaining its torque setting over time. There are plenty of 350 blocks available. I wouldn't mess with welding it up.

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Old 02-27-2026, 11:43 AM
TXSTARFIRE TXSTARFIRE is offline
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Out of curiosity, is that a common place for a block to crack and what would cause a crack like that?

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Old 02-27-2026, 11:44 AM
grandam1979 grandam1979 is offline
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It would cost more to have welded than a different block would cost you. My2¢

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Old 02-27-2026, 12:04 PM
bdk1976 bdk1976 is offline
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Curious what was the machine shop's opinion was (on being junk or not)?

I would scrap it and buy a 400+ CI block. I realize things have dried up quite a bit but if you're patient and resourceful you can still find them. NFW would I dump $ into a 326/350, especially one with a crack in it.

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Old 02-27-2026, 08:18 PM
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Not worth repairing, find a 400 or 455 block if you are rebuilding.

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Old 02-28-2026, 03:59 PM
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350 block with a 4.25" crank gets you 400 cubic inches too And in my case, 453HP.
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Old 03-08-2026, 01:44 PM
Goatracer1 Goatracer1 is offline
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I had my 389 block that was cracked in 3 places repaired by "stitching" it. I did not however have cracks at a head bolt hole. I think I would pass on that block.

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Old 03-09-2026, 01:21 AM
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Absolutely repairable but idk why I have an extra 350 block . I've hit a nice 455 w aftermarket caps , a 428 and a 400 . If it's not numbers matching to your car I'd just get something else . Plenty of stuff out there

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