I just got an '03 2500HD with the 8.1L and Alli trans. I'm looking for exhaust and intake first. Any recommended brands? What other mods are making proven power? All mods must not degrade towing ability of the truck.

Thanks!!!

 

Try a intercooled whipplecharger and a set of TOG headers.That will ****** the gooseneck horse trailer out of the mud.If you throw in some custom tuning to eliminate the top speed limiter you can pull the trailer at 150mph.

 

Before I go and total shoot my gas mileage to hell with a blower, I want to start with some stuff like intake and exhaust. What are the recommended brands out there?

 

Read these,

Flywaterguide's towing report.

8.1 Borla still for sale?

Tom Byrne's 8.1 toys.

You might try calling Banks and see if they are working on a 8.1 power pack kit. They usually try to get the most towing power out of a motor.
http://www.bankspower.com/