i just bought a 2001 GMC with 4.8 L and it has 113,000 miles, i'm kind of new to full size truck market as i came from mini truck scene, but my questons are what things can i do to get more power? it already has a k&n cold air intake and thats it. i was thinking some headers, but which one? cat back system, but which one ? high flow mass air sensors but which ones? also i've seen the the hand held tuners, but which one ? i see cams and heads being talked about also i've read on this site that people just swap it out for a bigger motor. or is there just to many miles on it that it up grading it wouldn't make a differance and i should just have it re-built

thanks for the help and replys welcomed.

 

Welcome to PT. Tune, LT headers, catback. Sound is a personal preference. Figure out your goals realistically. Decide if you plan on keeping what u have, since many are makin power w/ 4.8L. Other things can also be done to the motor. Puttin the power to the ground can be done w/ different gears, stall. Have someone like Nelson or Wheatley do a custom tune would be a good 1st, unless u know how to tune, which then you'll need something like HPTuners or EFILive. Hand held tuners have limits to what they can do. Is your motor &/or tranny in sound condition?

Post up some pics of yo ride. What do u have, stick or 4L60E? Rear gear?

 

My first step would be to do a search using the search engine on this site. I don't know much about the 4.8's, but headers, cat-back, and a tune would be a good start. Stay away from handheld tuners. Instead look to the right and you will find tuning companies that will send you a pcm already loaded with a bad-*** tune. Less money & much more horses! I let the others talk to you about which cams & stalls. If the motor hasn't been abused I wouldn't worry about rebuilding it yet. Best of luck and welcome.

 

https://www.performancetrucks.net/fo...d.php?t=395748


THERE YOU GO, ALL YOUR INFO CAN BE FOUND USING THAT SEARCH TAB TO THE RIGHT.

 

On my 4.8, the longtube headers,no cats with offroad y pipe, cat back, intake,and custom tune woke it up. I would do pacesetter longtube headers with offroad y pipe, cutout, catback (your preference), a custom tune for one of the sponsors, gears, and a cam.If that isn't enough, throw a little nitrous at it. YOu may want to do something with the trans also, a servo, shift kit, and possibly a high stall convertor.

 

or, just nitrous the **** out of it!!

that always builds power

 

Gears and tune IMO the most noticiable difference you can make... Besides Nitrious, or FI...

 

i have heard those stupid 4.8's are hard to get performance out of......


thats what my friend told me. there are so small.

i heard they are only 294 cubic inch, how could that go fast?

 

where are you from?

my tahoe was a slug, i did shorty headers, custom off road Y pipe, JBA cat back- replaced the JBA muffler with a SLP shotgun resonator, cold air intake, HPtuners i did myself, and a 175 wet shot of nitrous

im kinda of maxed out at this point, im going to port the TB this weekend, then do my LQ9/l92 top end swap in a month or 2

 

BTW, it never ends.