Hot Rods Chevy 454 Crate Motor Specs

My rod came with a LS6 454 crate motor, the casting dates are all 1990 and it has the 2-piece rear main seal. I'm trying to find specs on this motor but all my searches wind up with specs on the newer motors with hydraulic cams and 1-piece seals.

I need the compression ratio and valve lash specs and any added specs.

 

Just curious but how do you know it’s an LS6 crate engine?
You can maybe confirm some things by looking at block and head casting numbers and then look them up on the many sites.
I’d be surprised if GM was still casting LS6 heads in 1990, but I guess it’s possible

 

you need an old GM Performance parts catalog...I don't seem to have one any more that I can find.

4 bolt block, steel crank, 7/16" bolt rods, forged pistons with small dome, open chamber rectangular port heads, giving 9.0 compression. Street hi lift hydraulic cam (I think it's .500 lift), dual plane intake, 3/8" pushrods, probably has a nylon cam sprocket and link timing chain. I think they had the normal p***enger car oil pan.

I bought an LS-7 in a crate the last day of 1989...I had a pretty good idea at the time which engines came with what. But that was 30 years ago. Also, around that time a friend bought one of the LS-6 engines and put it in his off topic car. I think he still has it. Seemed to work well as a street engine.

 

I did a little more research, I was wrong on a few things...sorry about that.

here is the info from the performance parts catalog from that era.



The Chevy Power book shows .024 intake and .028 exhaust valve clearance for that camshaft.

 

I think they had a .540 lift cam. I bought a 427 ZLX crate motor and that's what it came with.

 

Chevy had several different cams, and different engines got different cams. The Chevy Power book from 1978 shows the 143 cam is .500 lift. The .540" lift cam for the L-88 427 has .024 and .026" lash. Different part number.

 

Jim, have you ever posted or looked at the Speed-Talk forum..?

 

nope.

 

Off topic engine.

 

But it's the same family as the 65 396. LOL.

 

Here's an LS6 454 with casting numbers etc advertised in the HAMB cl***ifieds

 

Thanks, squirrel, that's the info I needed.