I have decided to do an 80E swap to prepare for boost and have run across a couple LQ4/4l80E combo's for sale for around $1500 while searching for tranny's... For that price it's pretty tempting to go ahead and do a 6.0 swap at the same time. I know that I want a 01'+ motor, but my question is, what are the differences internally on 01'-06' LQ4's? I had heard that in 04' they upgraded to stronger rods, but I can't find any info searching??? Just trying to decide exactly what I should be looking for. Thanks

 

Yes i believe in 04 all of the LQ4's got the stronger ls2 rods.

 

Yes as a minimum you want a ’01 + motor, but as far as changes go they are minimal. Starting in ’03 they added the coating to the piston skirts to help minimize cold start knock, done away with the EGR and went to ETC across the board. In ’04 they changed to a fixed orifice PCV valve and switched to a return-less style fuel system. As you mentioned, somewhere around ’05 the LQ4’s started getting the LQ9/LS2 full floating rods, which are quite a bit beefier.

The changes are so minimal, that while I would prefer to get an ’05 or later if I were looking for one, if I were to get an ‘03/’04 model for a good price I wouldn’t lose any sleep and as far as that goes any of them outside of a ‘99/’00 model will work just fine and hold up to just about anything.

 

What kind of hp number's and lb's of boost will the 04+ motor's handle with un-touched lower internals???

 

what makes the 99-00s so undesirable?

 

Iron heads, and a longer crank which doesn't allow you to run a 4L60e transmission.