Re: 1966 Chevelle
If I recall correctly, back in the day, there was a service
bulletin issued by GM to all dealers alerting them to the
fact that some of the 360hp engines used 4-bolt main
blocks. I believe that this was done to avoid piston dome
confusion ( collision ) with the oval port heads.
I guess in a round about way I am saying that I believe both
blocks were used across the 360hp application.
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