I have a '77 1150 block...on this block, between the transfer port covers and the mating surface of the crankcase cover, there is 2 threaded holes in the block just outside of the inner main bearing journals....what is the purpose of these holes...i have 4 other L6 blocks and this is the only one that has those holes opened and threaded...all the other blocks have the bosses in the casting but the holes are not drilled and tapped...? Thanks!
