I'm getting ready to build a 5.3 to replace the stock 4.8 that's in my daily driver 2000 GMC Sierra 1500 Ex-cab 2wd. It currently has 237,000 miles on it but gets real noisy in the valvetrain when I do any towing so I'm staying away from towing now till I get my new 5.3 in it.

I've been given a 4.8 short block for free and will be swapping out the crank/rods and pistons for a reman. 5.3 crank/rods and new 4.8 flat top pistons probably from someone like Speed Pro. I'm going to put a freshened set of 799 or 243 heads on it with the OEM truck intake and TB. I want this to be a simple swap of my existing motor. Plug and play you could say. I do plan on putting some long tube headers on it right away also.

I plan on towing with this truck occasionally which is usually at the heaviest a 3500lb car on an 18ft open steel trailer. But mostly it will be a daily driver.

I'm looking for a cam that will give me lots of low end torque, good HP but have a nice sound. Around 300rwhp would be great.

My truck runs the stock sized tires but I changed the gears from a 3.42 to a 3.73 a few years ago with an Auburn limited slip unit. The trans is the stock 4L60E but was rebuilt with a new planentary and has a corvette servo so it shifts very solid from 1st to 2nd. What are your thoughts on this? With your recommendations what changes besides the obvious computer reprogramming would you recommend? TIA

 

I'm assuming you want to keep the stock stall? A comp cams 212/218 low lift version would be a good bet for you. Lots of low end power and you can keep the stock stall. With a good tune, headers, and this cam I'm sure you could make 300. You will need to upgrade your pushrods, and springs.

 

I wouldn't be against having to change the converter if necessary but being I have a 4.8 now and am going with a 5.3 I would assume my current converter will stall higher than an equivalent stock 5.3 converter?

And oddly this is one I was considering.
54-412-11 - XFI? RPM

 

That is probably the perfect cam for your needs. I'm not sure about the stall rate from the 4.8. You should have the stock 4l60e which would stall around 1600 regardless of the motor size. But either way if it does stall at a higher rate it won't hurt you any, and will in fact put you higher up in the power range of that cam, which would help you out anyways

 

Do you plan on headers? The triple 12 cam has been 300 + whp in an otherwise stock 5.3 with manifolds and dish piston/862 head.

 

Yes I plan on long tube headers. Possibly a Speed Engineering set. Isky recently changed their website and to be honest what I see so far sucks. I'd be interested in learning more about the triple 12 cams.

 

With the triple 12, 165a springs and isky p-rods, crappy 93 tune by a local, heads cleaned and shaved slightly to get square, CAI, e-fans, stock trans/converter, stock manifolds/cats and 2.5" bullet muffler dumped I made 300hp/310tq on a dyno.

I have since got 1 3/4" LTs, 2.5" ORY, 3" catback with straight through round muffler, and a good 93 tune from BlackBear and according to EFILive I'm now making about 340hp/335tq.

Again, this is through a stock trans and converter. Works just fine as is, but an aftermarket converter in the 2500-3000 range would really help get out of the hole a lot better.

EDIT: I also tow around 6k lbs a couple times a year just fine and very often haul a bed load of wood in the winter.

 

The more and more I look at the Vinci cams the better and better they look, they have like 2 or 3 grinds that looks like they would be sweet for a under the curve 5.3

 

What are the cam specs for these Triple 12 cams? Can't find them anywhere. I've looked at some of the Vinci cams also along with Texas Speed. This Comp is one I've been considering as I can get Comp thru my wholesale warehouses.
54-424-11 - XFI? RPM High Lift

 

The name pretty much describes the specs 212/212 on 112 lsa