Just found this posted by Texas Speed and Performance in an L92 vs Gen3 head thread on Tech:

 

If you do end up with L92/LS3 heads on the LQ9 with more cam, be sure to do an interference check with the valves. With no dish in the LQ9 pistons, there is potential for clearance issues depending on lift/duration of your upgraded cam.

Stock gasket is 0.051 so if you go to a thinner MLS Cometic-style gasket it can end up being even worse.

We ran into this on a swap project last year--

 

lq9 swap is almost done...hope to finish it up this weekend...i will keep everyone posted!

 

sounds nice, hope all works out for ya, i ran a stock lq9 bottom end with the ls3 topend, i milled my heads .015 with a .040 milled gasket using 7.400 pushrods, had NO issues and made plenty of torque and horsepower just not in the low end area of 2500 rpms lol!!

 

gotta question everyone...the lq9 intake is different from my 5.3... lq9 is off an 02 escalade and i have an 02 yukon...

the lq9 intake has an egr valve on the side of the intake near the throttle body where it bolts up to it but my intake doesmt have that

what intake should i use? r they both the same? any input is appreciated im kinda stuck on what to do next?

 

II would use the one off your old motor...less head ache with changin stuff, they are the same minus some port configurations, that can be swapped between the two but if you have a complete intake, put it on!


I love my LQ9/Gen IV mutt...my estimated TQ from tuners is 400.

Key point in this is to match your parts. I chose a cam that was matched for my heads and then the converter...any one of these parts that 'dont' work could negate any gains you might have had, I had cam only for a while and my converter was not match to it, I ran the same time b4 and after...

 

hey onyx...i do have the complete intake for the 6.0 off the 02 escalade but its missing that egr valve...

i would assume that the intake off the lq9 would suit it best...but if u say they r the same as my old 5.3 minus port configurations??? port configurations meaning less performance out of the 6.0?

i can always buy the egr valve and keep the lq9 intake if u guys think it will work best for me?

also FYI i went with the 317 heads or a stock lq9...i figured the l92s will be to much work for me

any input would greatly be appreciated...im actually working on that today...thanks in advance...

 

exactly why i went with the 317's....i would have to pay a proffesional to do the swap for me with the l92's and didnt wanna do that since it could of gotten pretty expensive...

so the intake off the 5.3 would work just as good as the intake off the 6.0? i know thse r dumb questions but i just wanna be sure and want the most out of my setup without restricting or losing any power

 

ok everyone...just about finished with my swap...

what do u guys recommend for any bolt on upgrades for my stock lq9???

by the way whats a stall? torque converter and its purpose...i mean i know its suppose to lock in ur gears longer or something but i dont quite understand how its used or benefits?

 

ok everyone i just finished my 6.0 swap...just to give everyone an update on my final outcome i have an 02 yukon with a 5.3 and i took a 6.0 lq9 and swapped out my tired 5.3 for the lq9

i used only the lq9 block and 317 heads and used everything else off my 5.3

i test drove my truck and it feels sluggish and kinda bogs out on takeoff and when i slam on the gas...when i do this my service engine light is on and starts flashing???
what does this mean??

also i ran the scanner to check the codes on the check engine light and i get a p0171 and p0174 the def is to lean and also p0300 a randon misfire??

not to happy with the end result...not sure what i did wrong or what i need to do to fix this?? please help out guys?