I own an 07 Supercrew and am wanting to replace the stock muffler with an aftermarket model. Will I seen any increases in power, mileage, performance, etc...? If it do a muffler swap, what aftermarket muffler should I use?

 

Si/SO offset dynomax or magnaflow.

2.5" inlet and outlet.

 

x2

 

18" inch Maggy Or maybe a 14" just cus it might be a little louder.

I can't tell you if there any performance gain since I didn't do it when my vehicle was stock. Most likely, there won't be much if any performance gain (maybe 1-2 HP?) but it does sound nice

 

just replacing the muffler, you won't see any performance gains. You still have all the factory piping causing a bottle-neck. To really see any kind of hp gain you have to ditch the piping from the cats back. If you want to see even more gains, replacing the stock cats with high flows and stock exhaust manifolds with long tube headers and then you will see 20-30 rwhp.

 

after replacing the manifolds with long tubes and then high flow cats, if you then use two mufflers that's classified as true duals right?

 

after the cats, you put a X-pipe instead of the factory Y. After that you can run a DI/DO or 2 SI/SO's

 

I did this earlier this year. Replaced with a Flowmaster Super 40. I think I actually lost power. Doesnt sound bad, but I want louder, and what my lost performance back. That is one reason why I bought a Edge.

 

Flowmaster= "Slo"master

Due to their chambered design for sound, you lose your low end torque. You need a straight through design ie: Magnaflow or Dynomax and you will not lose any

 

I am looking at going with either a Roush Off-Road, or a Corsa. Sound and performance!

 

Install a catback system and not just the muffler. The stock pencil pipe looks horrible coming out the back. I recommend the Magnaflow 16612 SISO catback. It's a 3" pipe with a 4" tip.

 

just cause you get a new muffler doesnt mean you have to keep the pencil pipe. you can always just have a SS tip welded on to the stock pipe

 

X2! Just replacing the muffler, and adding a tip alone actually sounds pretty descent. It also gives a noticeable power gain as well. Its nothing like replacing the whole system or anything, but its very respectable for what it is...

 

I dont have any way to test but I put a 5x8x18 magnaflow in place of the stock muffler on my 07 5.4 and I like it. I also added a 3" AF1 as well and could tell there was a difference in performance after each upgrade. I run all stock exhaust pipe, as I have read that with stock motors the increased pipe size is not warrantied. Maybe it is maybe it isnt. I can tell you this, with the AF and the maggie I am very happy....tunes for my X2 should be here in December sometime:santa:

 

Warranty only covers from the cats forward,and modifications behind the cats can not void warranty. Unless you mess with the cats and/or add headers you will have no problems.