I think they're pretty wierd too! I'm sure they aren't the motor mount bolt holes(see the gallery I posted).
I'm also sure they go through because with the road draft tube removed light gets into the engine and I can see through the holes into the engine.
They are definately not threaded or dirty, I just got the block back from the machine shop.
Like I said, wierd....
'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi
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