Ok. I acquired a LQ4. It's got high miles. It's an old Iron headed 6.0. I have arp rod bolts from my old LS1 and a crank. I also have a blown L33 short block.

I was thinking, the crank and rods from the L33 (since theyre floating) with the ARP bolts. Then either getting flat tops, or boring to 4.065 and run LS3/L92 slugs. It's going in my DD. I'd like maybe 450ish wheel. It's in a 2wd Yukon, with a lil weight reduction, so maybe 5200.

I'll build it one piece at a time. My other question, is cathedral or square ports? How would 243s with some work done be on a 6.2? I know alot of people say the Square ports, you lose bottom end. I'll of course stall it and a cam. I have 3.73s. Just looking for opinions from the gurus and getting knowledge on what will work. I'd really love to maybe hit them 12s.

 

450 rwhp is stout for n/a engine .what are doing for injectors ,throttle body and intake .

 

It's either going to take a high compression pistons with l92 heads or some ported heads to make 450 with an auto tranny..

 

I figured the heads would need some work. I guess my main goal is to hit 12s. And should I go with the 4.000 or 4.065 bore.

I planned on needing injectors, and either a L92 intake, or NNBS with 90mm tb.

 

While a lot of the 6.0 iron blocks can be bored to 4.065", not all can (especially the early blocks). If you seriously want to do this, have a machine shop sonic check the block. On the other hand, a 4.030" overbore is routine for these blocks and is what I would probably do.

 

It is an early block, so I guess I'll need to have it checked. I thought about a 370, but I'm trying to go budget. And I was going to get stock LS2 or LS3 pistons, due to being cheaper. Forget 4.030 slugs are considerably more.

 

A high mileage block will need to be bored out, so regardless you are looking at new pistons.