How much are you guys running? And would an LQ4 or LQ9 be able to handle more? My goals with a turbo are 600rwhp, but not without boring it out and a built motor. I just want to know how much it can handle as is.

 

it all depends on the tune and fuel system. I would think a stock bottom end will be alright at 500 or so with a great tune and some rod bolts. You could always have the 5.3 bored to accept off the shelf forged 5.7 pistons. With good rings, rods, and bearings, 600 would be no problem. Thats what Im going for with my 370. Well maybe 700 with the bigger turbo

 

That's what I was thinking, but that would cost alot of money wouldn't it? I would have to pay someone to do all of the installing (forged internals, boring, ect.). The only thing I could do myself is the turbo.


Let me know how it goes, I might change my goal to 700rwhp too.

 

Im doing the same thing with my 6.0. It was $650 for forged pistons, $200 for rings, Im using LQ9 rods $100. My builder is quoting me $990 for disassembly, cleaning, boring, clevite bearings, and reassembly. My LQ4 long block cost me $1K. Im doing the install though.

 

Check my sig. Its a stock 5.3 with 166k on it. Tuning and fuel are the main issue.

 

with a turbo i dont think rod bolts are required. there is some great info in that book maximum boost that tells you why the rods/rodbolts dont see nearly as much load with a turbo set up as they do in other set ups. the pistons are probably the weakest link. with a dead on tune i bet a bone stock 5.3 would handle 600rwhp for a long time. you would need valve springs but thats about it.

i was running over 600rwhp with a 6.0 that had nothing but valve springs, head studs and rod bolts. i ran that for most of a season and ended up blowing it up with a nitrous misshap. ahh, i think i had a cam too.

 

Huh, I never read about that part (I've read most of the book now, maximum boost). It's got lots of good info. Thanks for the replys. BTW, how much boost are you running jcfreak?

 

the book talks of peak load on the rods being right at the top of the exhaust stroke when the piston is changing direction with no downward force on it,it trys to fly out of the motor and the rod and bolts have to pull it back. you can reduce this peak load on the rod by having exhaust back presure pushing on the top of the piston. on a na set up back presure hurts power so you do what you can to reduce it but with a turbo it is just part of the game. also with most turbo set ups people dont shift as high. rpms are what kills most rods.

between lower shift points and the back presure pushing back on the piston when it is under max load the peak load on the rod(rod bolts espesialy) is actualy less with a turbo.

there was also some info about how the tq is developed over a longer time rather than a high peek. i dont remember what that part of the book was about. i might have to go read up on it again.

 

I knew it would be a waste to get this exhaust, lol. BTW, how is your exhaust set up, you're not even running a muffler right? Sorry for all the questions.

 

i have a bullet muffler and it exits out the side before the rear tire. it is prety quiet. i ran a cutout at the track.