I agree, an LQ4 would be great for your goals. Sure, it would cost more up front but it would require a lot fewer modifications to meet your goals.

 

thought i read somewhere that the cylinders on the 5.3's are kinda hit and miss on being thick enough to stroke it to a 383?

i'd love to do a 6.2 but unfortunately right now i can't and i need a temp fix before my current motor blows and that's why i'm looking at the 5.3's(plus i'm going to need 1 later for my jeep). i figured a cam, some head work, some tuning and alot of wishful thinking i'd be close to my desired effect. i wasn't even going to bore it unless absolutely necessary.

eventually when all my ducks fall in line my end goal is a turbo'd 6.2 but i don't see that happening for a couple years. i have to finish putting my jeep back together so i can tear my truck apart.

 

There is a thread on here where a guy dyno'd a fbo, stock heads/cam lq4 with a tbss intake and put 350 hp to the wheels. If I find it, I'll come back and post a link to it.

The money needed for head and cam work on the 5.3 will easily pay for a good 6.0 long block.

Keep an eye on pt and tech. I bought my Lq9 off of tech in '09. Got a pretty decent deal.

The only 5.3's I'd consider would be a L33 or a gen IV. Higher compression, better heads, better intake.

Imo, turbo w/e engine you end up with.

 

what does fbo stand for?

 

Full bolt-on iirc. It definitely means that the vehicle has all the bolt-ons.