Looking to start building an lq4 for my '01 ws6 m6. First time tearing into an lsx. Have built multiple sbc and lt1 motors. Looking to build on a budget, shooting for 450+ up on the motor. Bought a 6.0 lq4 from a friend of mine and have been talking about head options. Should I run the 317's or 241's or look for another set? Is my goal reasonable with the right cam?

 

I guess the main thing is what is your budget to spend on heads?

The 317 head is a larger chamber/lower compression version of the 243 head, where the 241 head has a smaller chamber/ higher compression stock for stock the 241 does not flow as well.

That being said with the right port work done on the 241 it can still flow very well.

 

The weak link in choosing a LQ4 are its dished piston and low compression for what LS heads can dish out.
You could send your 317s to be ported and decrease chamber size. By doing that you keep stock valve drop distance and can still put a bigger cam in while benefiting from added compression and the better runner design of the 317 casting.

 

So is my goal capable. 450-500? Have been looking at the ms3 cam or similar.

 

Flywheel HP irs, rwhp no...not with the stock pistons, mild cam and stockish heads....but good head work, aftermarket pistons and a larger cam yes

 

Just want 500 on the motor

 

Ok...that won't be that hard...shoot for around 11:1 compression, a mid 23x/24x cam, ls6 intake and injectors with a tune that should put you there.

 

Already have ls6 intake what about injectors throttle body....

 

Stock ported tb, I'd even ditch the MAF and go with an SD tune, and maybe 42lb injectors to be safe....but leave your stock injectors in until you are st the tuners....once the injectors have been swapped you csn not start the motor until the computer is tuned for them

 

Thanks for all the input. Should be picking up the motor in the next couple weeks. Will keep updates

 

Came across this thread and I am about to take on a similar project. Not looking for the 450 to 500 hp range, but wanted to build a mild engine. Installing into an S10, but just looking for something fun. Any advice or lessons you could pass on?

 

LeonbergerG hasn't been here for over 3 years.

 

Take a clean 5.3, install cam/exhaust, tune and have fune