sorry for showing my ignorance(trying to learn) but how do you tell the difference between lq4 and lq9 heads (some lq4 heads are aluminum aren't they) thanx joel
should have said they are 317 castings but from my 2 performance ls1 books 1 says another casting #, the other says 317 casting # but diff assem #, they are alum thanx

 

look at the casting number. from 00 (i think) all lq4's have aluminum heads. 317's and 035 (i think) are the 6.0 casting numbers for aluminum heads.

 

come on guys i need to know thanx

 

Head: 1999-2000, LQ4 6.0-Liter Truck
Material: Cast Iron
Part number: 12561873
Combustion Chamber Volume: 71.06cc
Compression Ratio: 9.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches
______________________________
Head: 2001+, LQ4 6.0-Liter Truck
Material: Aluminum
Part number: 12562317
Combustion Chamber Volume: 71.06cc
Compression Ratio: 9.4:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches

________________________________

Head: 2002+, LQ9 6.0-Liter Truck
Material: Aluminum
Part number: 12572035
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches

"What you need to know: THe LQ9 heads are found on the high-performance versions of the 6-liter truck engine, and debuted in the Cadillac Escalade for 2001. This head is virtually identicle to the LS6 head, with the same improved intake and exhaust ports, but like LQ4 head, it has a larger 72cc combustion chamber."


*directly taken out of the GM High-Tech Performance magazine May 2003*

 

does the lq9 have the d shaped exh port? does the lq9 head have a casting # of 035 only? if so the book how to build high perf chevy ls1/ls6 by will handzel is wrong where on page 28 it say lq4 and lq9 heads have the same casting # and assem #. maybe i got hosed by someone on this forum who was selling lq9 heads with a 317 casting # thanx joel

 

317 heads are Aluminum. Look for the 317 on the heads that is all you need. They are 71.06cc. The dif between lq4 and lq9 motors is in the pistons and not in the heads. Same heads on both motors. Yes they have the same D port on the exhaust side like the ls6 heads but they do not have the same floor in the intake. The ls6 heads have a higher floor on the intake.

PM me if you need a set of lq4/9 heads i have a set i am selling.

 

then what are the 035 castings?? joel

 

Head: 2002+, LQ9 6.0-Liter Truck
Material: Aluminum
Part number: 12572035
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diamter: 2.00-inches
Exhaust Valve Diamter: 1.55-inches