'70 SBC 4-bolt main block usage

[Bill B.]

Hi everyone,

I figured that someone on this board would be able to substantiate or refute the long-held rumor I heard of that 1970 model year SBC (350) 4-bolt main blocks being installed in all Chev pass vehicles that year. I know that my original July build '70 Corvette base engine (350/300) was a 3970010 block with "010" and "020" cast marking behind the flywheel area and in the timing chain area, which I have heard depicted a high nickel content. Yes, it was a 4-bolt main. I wasn't expecting my base engine to be a 4-bolt, but that's when the I heard the rumor mill indicating even the Impala had 4-bolt blocks that year.

Can anyone elaborate on this? Just curious ...

[Patrick B.]

[Larry E.]

Re: '70 SBC 4-bolt main block usage

The 3970010 block has to be one of the longest running (If not THE longest) running blocks available from Chevrolet.
Bought brand new a 1977 Chevy Sport P/U with the LS9 and the 4 Bolt Block was the 3970010. IIRC it was that block
for the 70 Z28 also. Picture below of the 77 Sport Engine. Still have it and is For Sale. Thanks Larry

[Edward J.]

Re: '70 SBC 4-bolt main block usage

The 3970010 block has to be one of the longest running (If not THE longest) running blocks available from Chevrolet.
Bought brand new a 1977 Chevy Sport P/U with the LS9 and the 4 Bolt Block was the 3970010. IIRC it was that block
for the 70 Z28 also. Picture below of the 77 Sport Engine. Still have it and is For Sale. Thanks Larry

Larry, would love to see a few pic.s of the 77 chev.

[Larry E.]

Re: '70 SBC 4-bolt main block usage

Larry, would love to see a few pic.s of the 77 chev.

Edward>Thanks for the interest. Look up Hemmings Ad #2403978.(Many Pictures) You will see a lot of similarities
to the 77 Corvette (Engine). Larry