I have a 2004 2500hd 4x4 silverado with a 6.0 liter. Upgrades on it are granatelli tuner, k&n intake, hedman headers, dual flowmasters. I want to put onbigger tubing for the exhaust and put the new offroad 44 series flowmasters with high flow cats. I think right now i have the 2.5 inch tubing(stock). I want to go bigger. For sure im a get the high flow cats and the new flowmasters. I just need some ideas for the bigger tubing. What size should i get it or should i even do it at all?I need ideas. Thanx

 

I would not go any bigger than a 3in exhaust, to big is going to reduce your back pressure, therefore resulting in loss of torque and power in the low end.

 

Actually, the stock dual exhaust pipes back tothe muffler are 3 1/4 inch....so once you`ve done the mufflers, the tail pipes are all I`d be concerned about. What`s your objective...all out street performance?, pulling a load? If you`re towing a trailer regularly don`t go too big on the tail pipes as you`ll lose some lower end torque due to reduced exhaust velocity.

 

I would leave your stock converters as there is very little gain there (1-2 hp), and your stock pipes to the mufflers. The go with a single in dual out muffler. You may want to add some headers as well as you will gain there much more than from the cats.

 

I already have hedman headers and love em. Sounds like im going to stay wit my stock erxhaust[sm=smiley16.gif]. Thanx for the replies.