With out pulling the engine can you tell if this is a 4 bolt or 2 bolt block from the outside?

------------------
Barry
70 1/2 RS Z-28
69 Z-28 Crossram
69 RS SS 396 Convert
69 RS ProStreet 638 G.M.
70 LS6 Chevelle
66 427 425hp Vette Conv

? on the block is ther a engine code and VIN stamped on it . Esp need something like the Engine Suffix code. All the 375 hp 396's were 4 bolt mains while the lower HP models were 2 bolt blocks

------------------
Jeff 67/68(2) & 69 RS's

http://hobbystage.net/camaro/hawaiiancamaro/index.html

If the code has been decked, you can look down by the oil filter. There's an extra hole by the filter. Plus the holes are larger for 4 bolt. I'm travelling and can't look it up, but I think the one for the oil pressure sending unit is 1/4 IPS for 2 bolt, and 3/8 IPS for 4 bolt.

I was thinking 272 blocks were all 4 bolt.

Can anyone help with my failing memory?

1969 Block ,could be 2 or 4 bolt main,check oil filter area,front hole 1/2" pipe thread and center hole 3/4"pipe both into the oil gallery and rear hole above filter has a 1/2" USS coarse-thread,which is NOT drilled into the oil gallery.Hope this helps,Dan