Will 6.0L LQ4 heads fit on a stock LS1 block?

What pushrods would I need and will pacesetter LTs fit on there?

Sorry if I sound stupid. I found a good deal from a friend and was wondering if they fit. If they do I am definitely going to buy them.

 

They will fit, but they have a larger chamber than the LS1 heads which will hurt your power. However, if you are looking to go FI then they are a good inexpensive head to use.

 

Whats the difference between lq9 and lq4? What do lq4 come off of

 

LQ4 came in the 6L trucks and the LQ9 came in the Esclades (among others). They are basically the same motor with the exception of the pistons. The LQ9 runs a flat top (IIRC) piston that gives it higher compression and thus horsepower.

 

lq4 came on 2500 trucks. lq9 started years later on the escalade and silverado SS. The lq9 flows better. The lq4 and lq9 both have 72 cc heads stock, but they can be milled way down.

One thing you need to watch for on lq4 is the earlier years had iron heads.

 

I'm a slow typer.

 

2001+ are alluminum and have a very similar runner to the ls6 head. Earllier heads were iron with different lower flowing runners. They all come with the 72cc chamber stock. All of the ls1 heads are interchangable on the motors.

 

So for FI a LQ4 would be fine also but LQ9 would flow a little better. thanks

 

They are the same after '01 - both use the 317's.

 

An Lq4 is exact same head as LQ9 after 2001? 317 casting?

 

From what ive read, yes.

https://ls1tech.com/forums/showthrea...t=LQ9+LQ4+head

 

They both use a 317 casting which flow the same as a 243 casting

its the internals of the motors that are different.

but the heads are the same

you shouldnt mill a head too far since then you could throw off the mounting and etc of the intake to the heads

02 i believe was first LQ9 on the esclade and they also come in SSS,VHO,Vmax,H2[ibelieve]
Lq4 is the work mule but is still a stout setup

 

so do the lq4 and lq9 flow the same?ive heard they flow like a stock ls6 head?

 

they are the same freaking head!!! the difference in is the internals of motor

and yes they flow the same as a 243 head. only difference is the CC but if you refer to the LS6 verson of the 243 head then it has lighter valves

 

lighter vavles please explain?

 

The "true" LS6 heads have sodium filled exhaust valves and I believe hollow intake valves.

 

LS6 243 heads had light weight hollow valves....

 

and the truck heads have?

 

standard solid LS1 valves....

 

so the lighter vavle are better or worse?