in my search to find a 6.0l for my 99 rcsb i stumbled across a lq4 with ls1 heads on it, will this work? wont the compression increase greatly? i thought the lq4 heads like the lq9 were based off the ls6 heads, so would that make them better than the ls1 heads? if i were to buy this thing swap a zo6 cam, roller rockers, shortie headers (smog, i live in cali), and a custom tune what type of numbers (hp tq) am i looking at? thanks

 

the 6.0 heads have a bigger comustion chamber than the ls6 heads..72cc i think v.s. 64 cc of the ls6 heads...stick some ls6 heads on it instead of the ls1 heads...i put ls1 heads on my 6.0..just because i got them real cheep and i hand ported them

 

Be careful buying that motor. The 1999 model LQ4 had a different length crank and came with iron heads. It won't be a direct bolt-in. In 2000, they swapped to the much better aluminum 317 casting heads and changed the crank out for the same one in the 5.3 and 5.7 motors. That made the 2000+ LQ4 motors a direct swap. The only real way to easily tell these motors apart is by the heads they came with, as the block and pistons are the same. If you physically have access to the motor, you can measure the back of the crank where it would mount to the flexplate. The 1999 model is about 1/4" longer than the others since it was designed for the 4L80. If its got the flexplate on it, the 2000+ models will have a 1/4" spacer between crank and flexplate, the 1999 won't.

In the past, I've seen several 1999 LQ4 motors on ebay where the seller has either removed the iron heads or replaced them with LS1 heads. Then they claimed ignorance or lied about the year model it came out of. Usually, a 1999 model LQ4 will sell for much less than a 2000+ model.

Of course if you are moving to a 4L80E transmission, it won't matter at all.

 

does it make more power with the ls1 heads? im new at all this

 

curious as well....

 

Ok so was wondering what your guys's end result was because I have a 2000 GMC 2500 truck with an6.0l lq4 and I think my head cracked. So was wondering about switching out to buddy's 241 heads off his 2001 5.7 camero z28. What would be my pros and cons.

 

The swap to aluminum heads and the short snout crank was 2001 model year and not 2000.