Flowmaster on 2500HD 6.0

crew2500hd · July 19, 2002

Has anyone done this setup that vette hauler did on his HD

"

His original post on GMTC:

"The factory 3" dual system back to the muffler would be hard to beat. I left in in place and installed Flowmaster's new dual 3" in's with dual 2.5"s out. By cutting the outside section of the rear "Y" close to the old muffler and then close to the "Y" and flipping it over, I was able to use all of the original SS tubing. The dual 2.5" out of the muffler were swelled out on the ends to match the 3" and welded in place. I still have the 2'5" openings at the muffler exit which is required to keep from loosing your lower end torque. The set-up looks factory and sounds GREAT! Nice and mellow at crusing speeds, but get out of the way when passing gear kicks in.

Total cost; Muffler $105.00 w/shipping, installation $15.00"

Being a newbie can someone explain in "Exhaust for Dummies"

terminology how this setup is done. It looks like he welded the factory pipe back on the one of the 2.5" rear outlets and

did not do anything with the other outlet. Any suggestions would be appreciated.Thanks

chane · July 19, 2002

I am thinking of going w/that setup or duals out the back w/stainless tips. I have the muffler sitting in the garage, just need to decide.

Dave Cooper (Vettehauler) sent me a pic of his setup, so I could have an exhaust shop do the same for mine.

Email from Dave - "Here you go. The section that I put the "x" on was cutaway from the factory "y" at the upper weld, then we flipped it end for end and welded it in to place. There was a small gap on the top edge to fill, but it can not be seen unless you get under the truck."

crew2500hd · July 19, 2002

Chane

What is the difference if you go with the stock pipe or duals

performance wise? Also It would probably be cheaper to go with keeping the stock rear pipe. Have you priced dual 2.5" pipes?

2k1 2500hd · July 19, 2002

I add the flowmaster to my truck early this year, just as flowmaster was releasing the new muffler. I had twin pipes run out the right side approximately where the original single pipe was placed. I kept every thing forward of the muffler stock.