This is a quote from the book How to Hot Rod Big Block Chevys byBill Fisher and Bob Waar (HP Books)
Page 4 paragraph 2 "Note: Hi-Perf cast into a block is not a 100% guarantee that the block has four bolt mains. A resonably positive method of identifying a block with four-bolt mains is as follows: check the threaded openings immediately above the oil filter mount. If there are two plugs--one 1/2-inch pipe and the other 3/4-inch pipe, the block probably has four-bolt mains. Of course, the only foolproof way to check for four-bolt main caps is to pull off the timing chain cover or oil pan and start counting the the main cap bolts."
I can give you some tips on removing the harmonic balancer if you like. You probably could use a timing chain anyway.
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Dale P.
Team Chevelle Member# 423
65 El Camino
72 Monte Carlo
"..you did you take the washer off, right?"
Whiners please point your browser to
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