Hey guys, I'm just another new guy to add to the slaughter!
I own a 2005 GMC Sierra with a STS turbo set up. I'm planning on making some big changes to my set-up and anyone who enjoys getting their brains picked would be great for me. Also if there's any other STS guys out here in LA or blower boys, or anyone really...let me know.

First question for any and all...Thinking/Desiring to swap the stock 5.3L Vortec V-8 for something pre-built...any suggestions? I was thinking of forging the pistons, connecting rods, etc...of the stock engine but figured it might be easier to buy something already built up and MEAN, and if it can fall right in-place without to much hastle would be a bonus. I'm gonna be running 20psi on my turbo so something that can handle that out of the box would be a step in the right direction. LS6's can't handle that out of the box can they?

Thanks for checking in and Glad to be on board!

 

You sure you got a 76mm, not the gt-67? A 76mm is HUGE for a 5.3. There are literally hundreds of options motor-wise. Post up a thread in the internal engine section and what your power goals are, 20psi means nothing, psi is just a measure of resistance, 20psi on a 408 and 20 psi on a 5.3 are two totally different things, 20psi on a properly outfitted 408 will be worth 1000rwhp, 20psi on a 5.3 would be ~650rwhp. Welcome to the site and the money spending will only go up.

 

Yup it's a GT-76, I realize it's too big of a turbo for a 5.3L. I bought it with the intention of getting to 1000rwhp while boring out the 5.3L. But now I'm rethinking that plan. Boring out and forging the 5.3 has it's limits and risks. And as you mentioned a 408 would be better suited for a 76mm turbo. But I figure if I'm going up in displacement why not go all the way? And who better to ask then a bunch of HP junkies that have WAY more experience than I do on what combo might work best! Thanks for the tips, I'll post this question in the internal engine section.

 

20 psi seems to be the borderline for lifting heads? 1000 rwhp is a big jump. You will find alot of week links in the drivetrain fast. Not trying to change your mind, but unless you are going to do most of the work yourself, its gonna get expensive real fast. Triple your budget and it will be much closer to the actual cost.

 

Welcome spoolin,
Always nice to see another Calif. HP junkie
Mark