I'm not up on my LSx motors as I've always been an LT1 guy but I have the opportunity to pick up a 6.0l LQ9(I think) from a local bone yard. The head castings end in 317 and are aluminum. Is this for sure an LQ9? The engine is out a truck but they don't know which one. Is there any other engine which shares the 317 head ie: 4.8 or 5.3? Also with an aftermarket cam, what kind of power can I expext this to make using the 317 heads without porting? Any cam suggestions and known dyno #s?

 

Interesting name. Were'd you come up with that ???


Zed

 

The LQ4 has 317 catings too. Try if at all possible to see what that thing came out of. And what year. It might not be an LQ9. Only way to check I know of is to pull a plug at check the top of the pistons. If they are dished its an LQ4. f they are flat tops its an LQ9.

 

Thanks guys. I searched my brains out and looks like I'll pull a plug and take a look. The core yard wants $400 for it so I'll buy it even if it's the LQ4. This is a complete motor with all sensors and an intake ,tb etc. I'm gonna throw it in my 2nd gen Z28 with a healthy cam. Is 400 rwhp a dream with the right parts? It'll have a carb so 230+ deg cams are no problem.

 

400 hp shouldnt be a problem with the right mods. Thats a great deal even for a LQ4. You will need to pull a plug to get the real answer.

The LQ9 only cam on the 2002+ escalade, 2003 Silverado SS, and the newer vortec high output. All of these trucks have drive by wire electric throttle bodys. If the one you are looking at has a manual TB, then its very likely a LQ4. In 03, the LQ4 went electric, but 2001 and 2002 the LQ4 was manual TB.

 

My LQ4 has the electric TB..

 

Yes, the LQ4 could have either TB,but the LQ9 will only have an electric TB. If his motor has the original parts and has a manual TB, then its an LQ4 for sure.

 

Forgot to check the TB but I just went to the core yard and pulled the only 4 plugs that I could easily. Looked like a flat top but really hard to see. How much of a dish is there? If one looked at the top of the piston ,how big is the diameter of the dish compared to the dia. of the piston? Would I even see the dish unless the piston is in the perfect spot ie: TDC?

 

Its a pretty profound dish. Best spot to see it would be bottom dead center. You know somebody with a borescope?????

 

Thats a good deal for either. Yeah bottom dead center is best way to check out.