Fellow Strokers, I just put a Bullydog Air Intake on my 03 7.3, now I'm looking to put on a "bolt on" turbo back exhaust system. I want to have a good sound and do what's best for my 7.3 as far as horsepower and economy. Just haven't talked to enough people to know if there is a noticable advantage in going with the 5" as opposed to the 4"...??? Is bigger better with exhaust ?? Sound? Power? Fuel mileage? ??? thanks

 

sound would be the only difference between 4" & 5"

 

i think there's sufficient research on here that says there is no significant gain or loss b/t the two.

 

This has been covered a lot. I think the only difference is sound.

 

I put a 4 inch turbo back system on from summit racing, its there brand its all stainless steel, it was about 400 bucks for the whole system, i ditched the muffler and put a peice of 4 inch pipe in place of the muffler, sounds awesome. the clamps are a little cheesy but its worth the difference in price i think.. It was very easy to install and i have had no problems with it. came with a very nice 5 inch tip that looks great. will try to post some pics if i can get my pictures to download into my computer... having some troubles....

E