plansch

Hi,

does anyone have the original documentation and specifications for the LS6 engine sold in the 90' GM perfomance parts catalogue under part # 366250 (engine code XAA)?
Or can someone tell me where I can ask for it?

Thx
Marcel

1977L48

have you tried contacting a dealership near you? i know mine was helpful with looking up very old cam stuff, from the 60's and 70's.

plansch

no, didn't try that because my next dealer is some thousand km away...
I'm not from the US... Do you have a contact for me who might help a foreigner?

1977L48

if you like i can call for you. is that the only information you have off the engine?

1977L48

ok, from what the parts guy at the dealership told me was, its a replacement LS6, 454-450 hp 500 ftlbs , 11.25 comp ratio, solid flat tappet cam, the entire kit and kabootel.

plansch

Thats a realy fast service...
But I think the comp ratio is not correct. In the '90 catalogue is said it has 10,2:1. I have a copy of the catalogue page and an original catalogue is on the way.
What I am looking for is more detailed tech information... as far as I know with actual crate engines there is a installation and tech specs document delivered with it. I don't knw if something like this exists for my 'old' engine. I'd like to have infos like recommended ignition timings etc...

plansch

here you can find the catalogue infos:

http://www.hemmings.com/parts/item/3844.html

1977L48

for that info i cannot help you, i would say run what the 70 specs was, im just going off what the guy told me over the phone from chevrolet. sry i could be more help

1977L48

XAA is a code for a 10.2 / 1 compression crate engine. GM substituted 118 CC Open Chamber Rect Port Heads on the XAA crate motors to get compression down to 10.2. Internally the XAA motors are exactly the same as the earlier higher compression LS6 motors. The only exception I can find in my engine is the change to the open chamber heads. Pistons, rods, crank and cam are identical between the XAA crate motors and the earlier LS6 configuration. I bought my engine new so I am sure it is as built by GM without any chance of anyone messing around with head substitutions

roadblock69

From memory, the short block is the '70 version with the stated 11.25:1 compression. However; The heads were the later open chambered design lowering the compression ration to 10.25:1. I also believe that the crate motor was not equipped with the 7/16" push rods. It came with the 3/8" found on earlier solid lifter engines. The heads are cast iron, had the big valves and rectangular ports. About the same as a '71 Ls-6 Corvette engine but with cast iron heads rather than Aluminum.

GOSFAST

Hi Marcel, don't have the OEM documentation any longer but I can add some info here!

These units were available in the early 1980 era, they are not actually considered to be an LS-6, there wasn't any "LS" connotation for them. They were sold by G.M. as "pump-gas specials", being the basic LS-6 short block but with the cast iron "open-chamber" heads. The C.R was 10.2:1 and these came out as the result of the "gas-crunch" of the 1970's, it was a "best-seller" at the time!

They were sold w/o the intake manifold, exhaust manifolds, distrbutor, or any clutch.

Thanks, Gary in N.Y.

P.S. I believe they sold for about $2400.00/$2500.00 or there abouts, not 100% certain!