Welcome! I wouldn't for 2 reasons. 1) It cost around 4-600 if not more depending on the throttle body. What I always think to myself, does this part match up to spending $1000ish on a 6.0 and all the power/tq it brings?

2) you will loose low end tq for the swap, yes it will bring more up top, but nothing crazy.

All I would do to a 5.3L for tq is boltons, cam, compression raise, other wise you might as well spend the heads and intake money on a 6.0 and cam.

 

I've got a fresh 6.0 I could drop in it but I just don't pull enough to justify losing mpg's.

Reason I asked about the intake is I happened to have one off a tbss but if it won't help for what I'm shooting for I'll save it for another build

 

You're not going to loose mileage installing the 6.0

In fact you may gain a little or at least the same IF you drive the same.

 

I agree, more low end tq means not having to push the throttle down as far. But for the 5.3L just keep it simple, b/c your only going to get so much lowend out of it, and gm already did a pretty good job of this on the 5.3L.

Cam, LTs, exhaust, CAI, e-fans, custom tune, and be done with it. Save that money for the project 6.0L
The cam I mentioned from vinci is real quite and idles like an ls6 cam. A guy on here is running it in a 5.3 and claims to get 22-23mpg with 3.42s

 

I had thought about turboing it but I read somewhere that the engine would overheat easily if under a load a while

 

Supercharger is the way to go for boost towing! I don't know the details of every aspect, but a supercharger will provide the lowend tq and will run just fine with a stock stall, vs turbos have to spool past 3K usually to make power. Your truck should mainly be running in the 2-3K band while towing.

Most of these N/a cams work well with a supercharger, but not so well with a turbo. So you could go ahead and build the motor like we have been talking about, and then if that is not enough the get you a supercharger.

 

Yeah I had read on that same thread that a charger would be best for towing. I'll prob just stick with n/a for now.

 

My supercharged 5.3 tows excellent and will maintain highway speeds uphill with ease, fuel mileage while towing is its only downfall to me, when not towing which is most of the time its a blast to drive.