75 l48 engine and head question
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
I have a 75 L48 and was wondering , is this a 4 or 2 bolt main and also what size valves are in the heads? Going to do an engine rebuild to keep the car numbers matching. Thinking about some head work and a mild cam. Not looking for a lot of H/P, just something thats fresh and a little pep in the mid range for cruising the 4 lane when needed.Thanks,
Gary
"Seasoned" 30 year-old metal is arguably superior to new metal, but it must be check for cracks, etc.
Thread Starter
Advanced
Joined: Mar 2007
Posts: 54
Likes: 0
From: King Of Prussia Pa
Check the casting number of the block. The Corvette Black Book shows 3970010 as the only casting used for MY 1975, for both the base and opyional engines. 3970010 is a four-bolt block.
"Seasoned" 30 year-old metal is arguably superior to new metal, but it must be check for cracks, etc.
"Seasoned" 30 year-old metal is arguably superior to new metal, but it must be check for cracks, etc.
Melting Slicks
Joined: Dec 2006
Posts: 2,669
Likes: 3
From: Kingston Ontario
My 3970010 is definitely a 2 bolt. Unfortunately casting number doesn't identify whether a 2 or 4 bolt. However pulling the oil pan and looking inside does! I do agree with previous posters, however; even a 2 bolt is strong enough unless re-building to ridiculous horsepower.
