1975 Engine block Info
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
Casting number 3970010 is a common small block engine casting. It was used in 1968 on the 327 2-bolt engines used in the "A" body, and it was used as a 350 block from 1969 through 1979 as both 2-bolt blocks and 4-bolt blocks in Chevy cars, trucks, and Vette. It was used in horsepower applications from 185 through 370. A common, universal block casting.
Lars
Lars
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From: Sunshine Coast, Queensland, Australia
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Well John. what matters most is the number on the stamp pad. The block casting number is just that. A foundry number of a casting. How it was machined after that is what matters. A L48 is a 2 bolt main. L82 a 4 bolt main. And of course the L82 got better/stronger internals.
I have had my 77 for over 30 years. I know it's the original engine. the stamp pad verifies that and know the history of the car. But I have never once looked for a casting number from the foundry.
I have had my 77 for over 30 years. I know it's the original engine. the stamp pad verifies that and know the history of the car. But I have never once looked for a casting number from the foundry.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,025
From: New Braunfels Texas
Truth is.....the 010 Block was a "belly button" block......it was used for several different applications and most were NOT high performance.......
All L-82's were 010 blocks...but not all 010 blocks were L-82's.....
It is no better or worse than any other 350 cast in that era really......and the 4 bolt means about squat because you will spin bearings on a stock block before you pull a crank out of one.....I have built 500+hp 383's out of 2 bolt blocks that only had ARP bolts as a mod.
Jebby
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