chevypro101
Full Member
- Joined
- Aug 5, 2008
- Messages
- 11
I bought a 2002 z71 avalanche with the 5.3.. I installed a k&N cold air kit, and cat back exhaust.. I had a hypertech programmer but it did nothing.. is there any performance upgrades that can be done cheaply that is worth it.. besides turbo, nitrous, supercharger I know some vehicles have factory parts that are very restrictive is there any in this case?? intake?? headers and so on?? thanks