Trying to decide which exhaust to purchase. I LOVE the sound of the Flowmasters. That deep rumble is definitely more my taste than the higher pitch popping sound of the Roush. However, the Flowmasters is just axle-back and the Roush attach at the mid-pipe. My perception after reading several reviews:

Roush= Better performing exhaust, good sound
Flowmaster= Better Sounding exhaust (for me), zero performance improvement over stock

Bottom line: I like the Flowmaster sound better, but the Roush sound is still good and if the Roush gives me better performance, I'll go with Roush. Keep in mind I am also installing the Roush M90 Supercharger, so I'm not sure how that impacts my exhaust choice.

Any advice is greatly appreciated!

 

Everyone has different taste when it comes to exhaust. Different people will try to tell you to get one brand over another. At the end of the day it's what you personally prefer on the car.

Personally of the two choices I'd go for the Roush.

 

Having had both the Flowmasters and Roush on my 2010 GT, I'd say go with Roush. I liked the Flowmaster sound, but it didn't come close to the Roush, IMO. I constantly get compliments on how mean my Mustang sounds. And FWIW, I also have the Roush M90.

 

If you want to stick with a chambered muffler, go with a Bassani catback and catted X. Bassani (IMO) gives the best of both worlds. They have that characteristic old school sound, but a little meaner, and their materials are a lot better than Flowmasters. If it were my car, I'd have a full Bassani exhaust, headers and all.

 

The bottom line is, the Roush exhaust is quite a bit louder than the flows.

I personally like the muffler deletes but they definitely have a lot of pop to them and sound very angry at WOT.

The thing that really rags me about all of the axle-back kits is how much they want to charge for a pair of mufflers, some tips and a little stubby pipe that connects it to the end of the OEM exhaust pipes.

Even the $180 polished 304 stainless muffler delete kit that is on my list is over-priced in my opinion.

 

Like you, I prefer the low pitched rumble and I'm very pleased with borla's stinger axleback. Part number 11777. Performance increased with these as well, No concrete dyno numbers- only judging from a 'seat of the pants feel'. Granted they're a bit more (by $150-200)than the flows, but the sound quality and and performance kick was worth it for me. Plus the borla's aren't a typical chambered setup a lot of v8's have.

At cursing speeds tho, there can be a slight drone at 1.8-2k.

 

I have Flows on my '05 and the internal baffles broke. So I called Flowmaster and they wouldn't do anything for me and they knew about the problem.

Go Roush

 

Typical shoddy Flowmaster build quality. The Roush exhaust does sound good, but I still prefer Bassani.

 

Roush

 

I also hear if you live an in area that sees a lot to rain/snow even just damp or humid conditions in general (costal) the flowmaster setup is prone to rusting...

 

I don't know the cause, but the driver's side rattles when you jump on it and It's annoying. Flowmaster is aware of the problem but wont do anything (I mean nothing at all). I don't believe it's a coastal issue as I live about 100 miles from salt waters.

Right now I'm considering Roush, JBA and Magnaflow as possible replacements.

 

Had the Flows on my GT, and have them now on my GT500... the stainless version of the A/Ts. If you're looking for performance with any axle-back, then look elsewhere. Gains, if any, are negligible. If you are seeking a more aggressive sound with little to no drone, then go Flow.

 

Has Corsa made a 2010+ exhaust? Their systems sounded really good, and made some pretty nice hp gains as well, IIRC.

 

Flowmasters here with no issues after 6,000 miles. No rattles, rusting, or signs of distress. I get looks, complements and thumbs up all the time when cruising by. I'm pretty happy for the money spent.

 

I installed a set of the square FlowMaster Thunders.. I picked them up off c-list from a young man who was parting out his recently departed Mustang for a hundred-bucks,,

I like the growling sound they produce,, but as one of the guys posted,, they do drone under 2-k and the pass-side rattles, not too bad but I can really hear it when I'm down shifting and engine braking,, I figured it was damaged from being the car being broadsided, interesting to read it may be a manufacturing defect,,

If that is the case,, you may wanna' chose another manufacturer ...

 

Thanks to all for the great advice. I went with the Flowmasters mostly based on it being the perfect sound for me, but I went out of town all last week and didn't see the posts here about the potential problems with the flowmasters. Hopefully everything will be alright.

Exhaust was the first mod...blower and suspension next...keep the great advice coming!

 

Good luck w/them.