I have an '86 Camaro 350 TPI with iron heads sitting on my shop floor.

Steve

 

While on the topic of base engines perhaps someone clear up something...

I think the base 327/300 engine from '66-68 was the L75. Correct or not?

Also what year did the L81 replace the L48? Was it '81?

 

When I built my stroker, I used a 4 bolt main block ... and advertised the OEM L48 including manifolds (intake and exhaust both) in the paper. the first caller not only couldn't WAIT to get down before anyone else, but he paid cash and was happy as a clam.

 

I think the base 327/300 Vette engine for 68 was the L-30

L-81 was 1981 and L-83 was for 1982

The L-48 was the code used in 1967 for the first time in the SS 350 Camaro. The 350 was not available in any other car at that time. The L-48 engine code was used for several years running in that particular application. This engine was also used in the Corvette as a base engine beginning in 69 but it was listed as ZQ-3 "base engine" through 72. In 1973 they started to call it L-48 base engine in the Corvette just like they did for the Camaro optional engine but the Camaro engine was rated at less horespower as compared to the Vette engine. This differences are due to two possible reasons:

1. The Camaro had different exhaust manifolds that were more restrictive
2. Chevy Marketing department wanted it that way.

I would put money on the latter.

-Mark.

 

I want to say the L30 was the base 327/250 from '63-65 and perhaps in previous years before the 'L' RPO code system. When they went to the 327/300 as the base engine, the optional L75 became the standard/base L75 in 1966 w/ the L30 being dropped from the Corvette. My presumption is the 327/300 L75 continued until 68 and was replaced by the L48 350/300 as the 'new' base engine but I'm not 100% sure on that.

THe problem is a lot of base engines lose their 'L' code identity so it helps to be up on any internal and engineering changes and what not. It's not always accurate to presume that an optional engine w/ the same HP on another Chevrolet is necessarily the same L code engine as a base Corvette. Especially back in the 60s when they were making so dang many permutations.

Ah yes, the one year wonder L81 and the two (production) year wonder L83!

Thanks. By '69-'72 lots of Chevrolet passenger cars had the L48 on their option list. Monte Carlo for example comes to mind. The ZQ3 thing is some weird factory build code thing they used for a few years and replaced w/ the L48. Somone that was an authority on obscure build sheet codes (John Hinckley?) explained all this about build sheet codes a few weeks back in regards to the L48 when someone else mistakenly said the L48 started in 73 on vettes. Try searching in this forum on 'L48' and 'obscure' and you should find the thread - You might find his post interesting.

Who knows what game they were playing - in other years, the rams horns vs log roll manifolds never stopped Chevy from using the L48 (or other) designation 'L' - that and the tack drive distributor and chrome ignition covers were different from 'other' L48s in '69-'72 but inside it's all pure L48.