Hello,

I just purchased a 2002 Chev. HD with the 8.1, I have searched this site but don't see a lot of posts on the 8.1. My truck has the alison trans and 4.10 gears. My first thought is to change the tires to 285 -75 instead of the factory 245 - 75's (which look to small), this would reduce my gear ratio to something more reasonable around town driving.
Any proven results with the Volant cold air system with the lower valance?
How about headers has anyone seen gains? I am thinking of the long tube.
The factory exhaust looks very good but is there a better muffler to hear the 496 but not drive me out of the truck?
I don't have supercharger money but thought the cold air and exhaust improvements but help.
How about the Westers computer tuning form Tbyrnmotorsports, any proven results?
I appreciate the feedback and I am anxious to make mod's to the truck but like every once want to make the correct ones.
Thanks,
Steve

 

My g/f's dad had a 05 2500 with 8.1L, 4:10's, and Allison. And he installed Superchip, K&N CAI, Dual exaust with no cats. It helped it a lil, but still didnt satisfy his taste he drivin D-MAX now. But if I was you I get a Custom Tune, Dual Exaust, L/T Headers, and the Volant CAI and it should wake that 8.1L up... Those 8.1L sound really good with headers and exaust.

 

I have a K&N intake on mine. It dropped 2 tenth off my 1/4 mile time. Westers is consider the best for the 8.1 but Nelson has some good results to. The Other Guy headers are a excellent product but are mid length. Stainless Works are full length but I've heard of some fitments problems. I good muffler will make a difference too. If you want to get anymore involved a cam is a big gain. When tune right fuel mileage seams to be not effected by a cam upgrade.

 

Yea from what i have read in the past you can get almost 50 hp from a set of long tubes, and a good cat back.

MY list of mods when i ever find a black on black 2500 burban are

1) Volance intake,
2) Stainless works long tubes, high flow cats.
3) borla or corsa cat back
4) Rhyler heads, maybe cam
5) Whipple blower down the road.
6) build the trans cause im sure it will die

Also you can try the little parts like the throttle body spacers, air foils, things like that. From what everyone has told me the 8.1 is very stopped up. Also if your into boats. that same motor is making 100-150 hp more so there is plenty of power to be made.


Check this guy out, he is the only place on line i have seen 8.1 parts.

http://www.tbyrnemotorsports.com/81truckcatalog.html