With LS2/LQ9 pistons the 862 cylinder head would make for very high compression. You'd be mid 11.x:1 range. I'm going to try to get some video of the torque I'm talking about. I can climb hills with the converter locked in overdrive from 1100rpm on up without having to give it enough throttle to unlock it. You could have the chambers polished and bring the compression down to a better range if you wanted though. With the LS2/LQ9 pistons the best thing is the 243 heads. These 862's with the bigger valves like I had put in them (which Baker Engineering did a beautifull job on) flow pretty well and with some porting are big power makers. Check over at LS1tech and you'll see some impressive dyno numbers using the 862's. Other than nitrous and boost, the best thing for torque is compression and cubes. A high compression 6.0L does that well. I plan to do a few others just like this one in a few friends heavier trucks with 80E's.

 

Yeah I knew those heads were very good on a 346 cube motor