I have a Sierra Denali..dont know why they came with LQ4s..thought they would have come with LQ9s. But anyways what is the difference between the both the Vortex Max and the LQ4 mechnically(Is there a LQ4 version of the VMax) or Is it just a tune?

 

VMax (LQ9) has a higher compression ratio. Same heads, block, and crank, but beefier rods and flat top pistons with a special coating on them. LQ4 is about 9.4:1, LQ9 is about 10.1:1 IIRC.

 

cant believe they stuck them in the older sierra denalis..Hmm..maybe LQ9 wasnt in production then.

 

I actually see it as an advantage...we can run 87 if we want, while the high comp guys really cannot. Also our engines are actually more favorable for forced induction. Finally replacement LQ4s are easier to find and cheaper.

 

Good point

 

2005+ the LQ4 got the better rods and coated pistsons. The CR ration is higher in teh LQ9.

I dont understand the big price difference between the 2 engines, esp after 2004.

peace
Hog

 

I thought 2005+ denali's have the LQ9?? my motor came out of a 2005 denali and after alot of research, I was told it was an LQ9 not LQ4?

 

From my understanding only the escalade and HD silverado/sierra trucks got the lq9.

 

The HD Silverado/Sierra did not get the LQ9, they had the LQ4.
The SSS and Vortec Max got the LQ9.

 

It depends. From what I found it looks like in 05' the Denali Sierra got the LQ9 and the Denali Yukon got the LQ4.
I don't understand why they would not use the same in both?