The current exhaust exhaust is 2.5". Even at 3" I doubt the gains would be noticeable; this exhaust mod is nearly 100% just for sound.

If I were you and I wanted to piece something together, I'd get a 2.5" in, 2.25" dual out muffler, a straight piece of 2.5" to make up the length difference (because the stock muffler is huge and the new one is like a foot shorter), and another piece of 2.25" straight or pre-bent 45* or whatever you need to make up the bends for the tips, then finally the tips themselves (obviously 2.25" clamp side and 3 to 4" outlet).

I'd want muffler and pipe T-409 stainless, and tips NEED to be 304 SS (so they will always look brand new after rubbing with steel wool and/or cleaning), because of corrosion resistance. If the cost is a deterrent, the one long straight piece of 2.5" pipe could supply the tip bends if you got a 2.5" in/2.5" dual out. If you're doing a set-up like pictured above, the run of pipes after the muffler is so minimal that the impact of pipe size is likely negligible, so dual 2.5" is fine.

Now, because I like getting stuff I can install myself and take on and off at will, I'd get this:

Offroad - http://www.roushperformance.com/part...2004-2008.html
Legal - http://www.roushperformance.com/part...2004-2008.html

I can personally vouch for that sounding bad A! That's what I have except duals out the back. That kit is "offroad" and loud, but they have a "legal" verson, which a buddy of mine has on a 2004 5.4 that I have heard many times in person and also sounds superb. That Roush muffler is a Borla. If pieced together, you've got $150 in tips, $200+ in muffler, and then pipes and clamps all properly mandrel bent and made to fit together. So well worth ~$550 shipped IMO because I know it fits and I won't have to pay to have anything welded and I can do it myself.

 

No you don't have to have all of them. Just my recommendation for a good heavy note deep toned exhaust that will feel as good as stock in low rpm but perform better when WOT. You can run the stock exhaust up to where the OEM muffler is and put your ProXS in and run dual 2.5" back from there. Have a listen to my YouTube video in Sig and you will see why I suggest the setup I have ( all the pieces that is no my muffler ) theres is zero restriction except for the manifolds. Pure thunder.

 

Ok I think I understand better .

I was thinking of going with tips like this http://m.ebay.com/itm/201024208759?nav=WATCHING_ACTIVE
Also do you know anyplace that sells decent piping for exhaust ?

 

Those probably aren't stainless. Flo-Pro's website doesn't list any "black stainless steel" tips and you might not even be able to powder coat stainless at all in the first place. They're priced like regular steel tips. But if those are actually stainless (which the grade of SS needs to be known), then they're well priced.

 

I went to there website and found a black tip section.

do you guys think an 18 inch tip is too long for this side exit?

 

Yes, black tips. Not stainless black tips.

 

18" tips are perfect for a 45° angle side exit before tire. If you want them straight level then I would suggest the 12".

 

I was under the impression that Magnaflow was used on the Roush kits.

 

Nope. Roush went to Borla Exhaust and developed the two systems and two specific mufflers strictly for these systems. The 'Legal' version consisting of an 18" or so oval case SI/DO, and the 'off road' version, being a 9" case oval SI/DO.

 

Darren is exactly. I didn't know the case lengths, but my offroad one is quite small and I knew they were "special" mufflers made just for Roush.

I heard my buddy's legal version and immediately went and bought my kit cause it was "the one" for me, but I don't even like how Maggies sound at all at low RPM. Been hooked on Borla since.

 

I liked my old 11" oval Magnaflow setup but under WOT it rasped bad. Nature of true dual I suppose.

My 3" single midpipe doesn't do this with a smaller muffler.

 

Maggies sound great when you get on them, but the really low RPM sound, like right as you begin to hear the exhaust sounds really weird to me. I can't describe it at all haha, and it isn't a "bad" sound, and it's certainly a very unique Magnaflow-specific sound, it's just not my cup of tea. It's only in person too, cause I've never heard it in a video. I want to hear it again, cause I feel like an troll because I can't describe it. Both of yours sound good.

I kinda like a little rasp when you stomp on it real hard, just cause it's like the tone "breaks" when the RPMs shoot up almost instantly. But all-the-time rasp like from straight-pipes isn't good.

0-85 MPH? I know that wasn't the speed limit

 

, neither was my 30mph 3rd gear pass in the video with the maroon truck .

I think I know the tone you are speaking of. I think its just the fact that I had always had chambered exhausts on my previous vehicles and Magnaflow was my first straight through setup on any vehicle. Still haven't had Borla yet. Next time round. I had GMMG catback on my WS6, and Super 44s on my 2005 Silverado 2500HD 6.0L. Loved the sound of both on them but appreciated the cleaner tone of straight through on Fords.

 

Yeah, any straight-through is gonna sound different/better than a chambered, so I'm just picking on the best of the best haha. I do like FMs on certain engines though.

 

**** now I am all up in the air about what I want to get. I think I am going with borla for sure, but now I don't know what size muffler to get. I think I was looking at the 18 inch but what would be better? getting a longer or short muffler? and my muffler is going to be 2.5 in and 2.5 out right? I just want them to use the stock pipe size. I don't want to change everything to 3 inch if there is really no gain.