Count me in on the 600+ rwhp lol but I'll start with lt headers first then work my way up

 

Are you serious? You think a 4.8 in a cc isn't cablable of getting out of its own way? I bet you $100 with full bolt ons, cam and milled heads, I run mid to low 13's. It will be later in the year likely before it's done, but with the gears and converter, without longtubes, I bet I can squeak a 14.5 out of it as long as traction isn't an issue (no dr's yet).

The 4.8 is weaker than the others in stock form, mostly in the torque catagory. Do you realize with a decent converter, torque (in the range the 4.8 lacks) is not even an issue. So then your working with a 15 hp difference with a 5.3?

BlackGMC ran the same kind of times that most run with cammed 5.3's. I know cajun and v8 were exceptions, but there is always an exception. There have even been people hit 13's with just bolt-ons.

Will I eventually change the engine, probably. But everything I'm doing will carry over.

 

I ran mid 14s with intake, tune, full exhuast in my ext cab with 26" tires. If your worried about the warranty, at least put in some lower gears and that should help you out.

 

I'm sure the gears you have in that thing are 3.23's, so thats a major hit. 4.8's in the Crew Cabs with those gears are horrible. At least some 4.10's and a 3000 Stall Torque Converter, ditch the flowmaster for a 3" single in/out magnaflow or something similar exhaust, get the tune, and I guarantee you will be much happier.

I guess I'm one of the few thats actually happy with my 4.8 liter, even with the few mods that I have, of course mines not a crew cab either. lol.

 

Waste of money. Magnaflow will maybe increase HP what, 2 or 3? Not worth it IMO.

Everyone on this forum is on Magnaflow's nuts

 

I've owned several sets of flows, first set was the 13" 2 chambers on my 90 GMC. They sounded good. I have a magnaflow now because I wanted something different. I like the magnaflow better. I liked the flows before they came out will all the b.s. models like the deltaflows etc.

 

i had a 4.8 once hence the ONCE part lol. it was ok in a rcsb for gas and that was about it. u want power Like Gs said turbo or like i said built 6.0 it all comes down to how deep your pockets are just my two pennies.

 

ohh and 2 the muffler conversation had both flows and magnaflow didnt see any gains over stock actually felt like a lost a bit down low over the stock setup, but i do like teh sound of the maganflow except that it drones like a ****

 

I went with a wheatley tune, he seemed the most customer service friendly and answered a lot of my questions quickest. I went with the 87 tune for now, I'm gonna change the cam and put in 4.10 gears after this summer. I'll retune with the 91-93 when I get those put in. Is there a link to $2500 turbo? That maybe an option. Anyone know of any good performance shops in Miami/Ft. lauderdale area?

 

https://www.performancetrucks.net/fo...d.php?t=477390