iregret

iTrader: (4)

After doing a lot of searching, it seems that folks on this site really like to turbocharge 4.8 liters. I posted another thread about the differences between the gen 3 and the gen 4. That thread answered most of my questions, but an interesting question came up. So I decided I'd start a new thread in the forced induction section and see what you guys thought.

Let's say you have a KBracing or Trick Performance turbo kit. A 76mm turbo, 3.5" down pipe and an intercooler. What truck engine would you run and why?

To make things easy, let's assume all three engines are sitting in front of you. They all have 100k miles on them and cost the same amount.

Some information that I've read about the engines.

4.8L

This is the way to go! Didn't you see that Hot Rod magazine article? The boosted over 1200 horsepower out if that thing! It's obvious that you'd be a fool not to run the 4.8L. It has the thickest cylinder walls and shortest stroke! This makes it ideal for boost.

5.3L

Uhh, hello!?! The 5.3L came in the truck. This would be the way to go! The only difference between the 5.3 and 4.8 is a couple of mm of stroke. It doesn't make that big of a difference! Especially if you're only boosting to the 650hp range. You'd be a fool to not go with the 5.3L!!

6.0L

So let me get this straight... You're going to the trouble of swapping an engine and you're not going to put the biggest one in there you can? Forget all that babble about cylinder walls and rod length. The 6.0 is the way to go. It's got the most displacement and won't be a total turd out of boost. Torque for the win!!

Sorry I paraphrased those last three parts. LOL.

Chevy_King1500

iTrader: (7)

power goals? 6.0 with 76m charger can make 500hp easily and safely.

AndysC3

iTrader: (14)

My 6.0L will spin all for on the street. Try doing that with a 4.8L lol. IMO. If you are swapping a engine might as well open the engine and replacing with some forged parts. Or at least open the ring gap some

03sierraslt

iTrader: (22)

If you already have a 4.8 then I would say rock it. If you are picking from the three I would do a 6.0 for the TQ.

iregret

iTrader: (4)

I'd like to clear 700 horsepower at the fly wheel.

I was hoping for generalizations and experiences in this thread, but here's a bit of info about my build up.

2000 Silverado RCSB
4L80E, hd2
NP149
Trutrac, 3.73
Ls1 fans
60lb injectors

My truck weighs around 5300lbs.

What prompted this entire thing for me was tearing into my 5.3L. I want to install arp rod bolts and studs, ls9 head gaskets, ls6 cam and springs and ls7 lifters. I figured, why tear into my stock engine when I could do all this on an engine stand and save my stocker as a back up?

I need my truck to stay drivable enough for my wife to use it.

iregret

iTrader: (4)

One other thing I've wondered about. Outside of boost, does the 4.8 get better gas mileage? Or is it negligible?

AndysC3

iTrader: (14)

in a 5300lb truck, I doubt it. It will be sluggish out of boost.

Johnmaster

iTrader: (3)

Torque converter would play a big role, my stock converter was tight and made it feel like a pig, now that it's right there it's as torquey as anything.

iregret

iTrader: (4)

Oh I guess I forgot to mention my torque converter. I've got a Yank SC3000 torque converter. So I figure a 3000 stall should help with the lack of displacement.

02'Z71ONDUBZ'

iTrader: (8)

4.8 or the 6.0, but it all depends on how you use the truck and how you want your power. Any of the 3 can get you to your goal, how do you need it to act under the curve? I'd forget about the rod bolts, and definitely pick out a better cam if your going to push it hard enough to need studs and LS9's. That converter will work well regardless.