8.1
 

My friend has a 2002 Chevy Avalanche 4x4 2500 with a 8.1 in it. We are looking into exhaust systems to improve his MPG and performance. Any suggestions out there? We are looking at cat back systems, but are considering a mufflershop also. We are also looking into a Cold air kit or a red neck ram air or just even a K&N filter. Any suggestions on these 2 greatly discussed subjectswould be appreciated greatly. Also are there any more suggested performance parts?

RE: 8.1
 

go with the k&n CAI and the flowmaster single in dual out mufflar. just get you mufflar shop to do it. shouldnt be to expensive. sould get a 2+mpg boost if your easy on it.