BB Timing Cover Dowel Pin Holes

[Dan M.]

Can someone tell me if all BBs from 65-71 come with Dowel pin Holes in the timing covers and if not which year and HP rating. As always thanks in advance for your comments.

Dan
NCRS 35068

[Joe L.]

Re: BB Timing Cover Dowel Pin Holes

Dan------

1965-67 big blocks used in Corvettes (as well as other Chevrolet cars) of all horsepower ratings did not use dowel pins and, consequently, the timing covers did not originally have dowel pin holes. Big blocks beginning in 1968 had the dowel pins and the timing covers, consequently, had the dowel pin holes.

SERVICE timing covers available from GM for all 65+ big blocks since about 1969 have had the dowel pin holes. The holes cause no problems for SERVICE with engines blocks that did not originally have the dowel pins. They may cause a problem for JUDGES, though, when judging 65-67 big block Corvettes.