What is LQ4 and LQ9? I have a slight understanding that they are heads.

 

pistons

 

6.0L motors....

LQ4 is the standfard issue 6.0L that comes in the HD trucks and the LQ9 is the 345HP motor that comes in the Escalades and such.... There is more but im eating a burger and dont wanna type it all out. lol

 

Both 6.0's. Higher compression on the LQ9. Due to the flat top pistons in the LQ9 versus the dished pistons of the LQ4. LQ9 has alot beefier rods too. Heads are the same on both motors. Except for some of the older LQ4's that had cast heads instead of aluminum. Is that what you were wanting to know?

 

Why on earth would you need beefier rods in a LQ9? All the LS rods are forged powder rods, and we all know an LQ4 bottom end can hold over 800hp at the motor.

Maybe parish should have pulled the pan on the last 6.0 to see if there was any unusual wear with all the abuse.

 

Would a 6.0L head swap hurt my 4.8L engine? Also, when I decide to buy my radix supercharger. Do I base it by the 6.0L head or the 4.8L motor? Forgive me, I don't have have that much knowledge on 99+ engines.

 

Everything bolts up the same, no matter if you have a 4.8/5.3/5.7/6.0. Everything is interchangeable and have roughly the same dimentions on the outside.

 

The 6.0 heads will hurt compression without the aid of the SC. The larger combustion chambers will help when you do get the supercharger.

 

If you are choosing between the 6.0 engines, most folks seem to prefer to boost the LQ4 as opposed to the LQ9. The LQ4 is a lower compression engine which allows them to run more boost. Someone shoot me if I'm wrong. Also the LQ4 should be a little easier to find.

 

The heads are not the same on both motors. the heads on the lq9 are the same as the new C6 corvette 6.0L, they call them fast burn heads