I've got an INSANE deal pending on a '99 Vortec 350 longblock out of a K1500 Suburban, VIN code "R". It's got the 062 heads, and what is beleived to be 4 bolt mains. I've told the seller it's a deal, pending the 4 bolt mains. It's a local garage that pulled the motor for a blown head gasket, and he hasn't had a chance to check the mains yet.
I'm researching allover the net, but have yet to come up with a conclusive answer. You now have all the info I have. Anyone care to lemme know how to tell for sure????

....obviously I'll check before purchase, but it'd be nice to save everyone the hassle if it's only got 2 bolts.

Thanks Guys.

 

2 or 4 it doesn't matter

The 2-bolt main blocks are actually stronger anyway when converted to 4 bolt splayed caps

No real way of telling short of pulling the pan

The JUNK 1997 G1500 Express shortblock that I have sitting in the garage is a 4 bolt main.

 

Could be either.. you'll have to pull the pan to know for sure. For a performance application though, the 4 bolt mains aren't much better than 2 bolt mains, because they are all straight up into the block. It is a little bit stonger, but only a little bit. Not enough to pass on an otherwise good deal for. Plus, if you really want 4-bolt mains, and machine shop can do that for you, and in the 'splayed' setup, which is quite a bit stronger.

 

unless your going to be using big power adder 2 or 4 doesn't really matter.