How to Identify a Small Block Chevy (Chevrolet) Engine

[@phillipthethird42]

Good stuff, I just came across a 3970010 block myself and am looking for any info that will help me identify this engine.

[@troyd7464]

What if i have no marks up front?

[@beeasy4360]

I got one of these number casting it’s a 350 2 bolt main

[@lustylusty1238]

My engine has same casting numbers as these ones on the heads and block. V1216CMH.

[@krapman9849]

CMJ code well tell you what car the engine was fitted to

[@raymondmenendez6499]

How can I tell how much horsepower my 350 has ?

[@donaldalbershardt6854]

DYNO.

[@jeeptk]

In 1973 and 1974 GM lowered the horsepower rating by limiting the throttle opening on small blocks.

[@lt.langle]

Had to. The gov was shutting ppl down for emissions

[@dalevackar182]

Please explain this.

[@jeeptk]

Yes all manufacturers had to start lowering the HP numbers and raising fuel mileage in the early 70s. The carbs had a small lever attached to the choke levers that limited throttle opening. It’s was a cheap easy way to make the government and insurance companies happy. If you come across a Q jet carb on an original small block from 73 or 74 you will see that wide open throttle is not wide open. Other manufacturers retarded the cam shaft in those day almost to the mid eighties. 351M ford engines were dogs with no power unless you updated the camshaft. It wasn’t just GM killing hp.

[@lt.langle]

@@jeeptk yeah government regulated it, my dad used to hold a lever back with a rubber band to give it more power. Even know the government put a limit on hp. Most companies lied and have more hp than they say bc the numbers didn't compare 170hp wasn't like it was 10 years before that

[@lt.langle]

Can someone help me I have a motor that's old. It should be a 307 or 350 I can't tell. I have numbers but they mean nothing to me. I think it's from 1955

[@FredColberg-jk5yp]

And 327s

[@donaldalbershardt6854]

327's too.

[@jimmylujan1457]

Can't see the number