Which Mufflers to go with?

[TrojanMike67]

Hey Guys,

I have a 2003 Mustang GT. The car is completely stock and I was thinking about installing new mufflers on the car. I'm hoping to get better gas mileage and performance out of the new mufflers. I don't plan on adding headers on anytime soon and would prefer just installing mufflers, not a catback system. I drive the car long distances, so the gas mileage improvement is my biggest concern. So, what would you guys recommend?

Thanks in advance !
Mike

 

[Screwed2V]

Magnaflow makes great stuff and it sounds good. I had those on my car before the engine build up and I then went to good old Flowmaster. I won't run any other muffler now as I just can't get over the old muscle car sound. I love the sound of the Borla Stingers too but I haven't owned them so I can't comment too much about them. You'll get tons of suggestions on this one and mostly people claiming that what they run is the best so I suggest listening to as many combos as you can and making up your mind from there. www.mustangexhaust.com

 

[Go Heels]

Flowmasters

I agree with micool, I've got 40 series Delta Flows on my 2000 GT and I love the sound. Alot of people wine about the drone at 1800-2200 RPM but it suits me just fine. Flowmasters were made to be on Mustangs..END OF DISCUSSION.

 

[TrueBlue03]

I love my magnaflow catback with magnapacks. They have an awesome deep burbly tone under 2200 rps. Then once you get above that they start sounding really racey. Can't get enough of that sound.... Got my catback off Ebay for $330 with free shipping. Great deal.
--I had the American Thunder set up my old 96 GT and that sounded nice too. Only problem was that nearly EVERY mustang has flows on it. I like the sound with the magnapacks a lot better.
--I've read Borla sounds awesome too, but i haven't heard a stang in person with them. They're more expensive though.

As for gas mileage.....I should be getting better gas mileage than stock, but i don't because i ride around at drone and like to rev the car a little at times

 

[mike4814]

If your going to change the mufflers do a new catback; dont have mufflers welded into the stock 2.25" pipes. When I got my 02 gt I had 2 chamber flows welded in I wish i would have just done it the right way to begin with. The flows gave it a nice sound the only thing i heard is that chambered mufflers dont really make power on the new modular motors (not sure if its true or not). I recently installed a borla stinger catback and bbk offroad x on my car and all i can say is WOW! The stinger really sounds bad ass it's deeper and alot louder then my old mufflers and its made of stainless steel. By the way Huston performance has the stinger catback for $460. If it was my car i would go with the borla catback but the flows sound good too.

 

[Virgil]

Bassani

What about installing a Bassani system with the "x" pipe?
I just got a 2004 GT and I was thinking of trying this system, but I'm sure what it would do to the emission stuff.

 

[8cyl]

ORIGINAL 40 SERIES FLOWMASTERS....then get a prochamber....

The combination is amazing!!!

 

[el gato]

I wasn't sure either

I just took a gamble. After much reading and research, I went the affordable route but yet still expect to be delighted. My Flowmaster A/T's catback arrive tomorrow (5/6/04) and I'll be installing this weekend. Can't wait.
Got them for $346.00 delivered from complete exhaust.
For the 2003 GT, the part # is 17312, that's what I got.
Can't wait. Hope it puts the stock to shame at least.

 

[todd4566]

I've had Flowmaster 40's, and Borla XR 1's. From inside the car, both sets of mufflers sound very similiar. The XR 1's are more expensive, but I got them to get away from the typical sound everyone else has. The Flows do sound good though, along w/ almost every aftermarket muffler setup. Hard to go wrong changing mufflers on these cars.

 

[Superhereaux]

save your cash and buy a catback. if you buy just the mufflers now, you'll probably end up buying a catback sometime down the road anyway

also, buy a quality stainless steel catback that will last, NOT flowmaster. they're aluminized steel and will rust eventually. especially if you just buy the mufflers and have them welded on. the welds will rust up and then the mufflers soon after

remember, most catbacks (straight through) will give you around 10hp and half of that comes from the smoother mandrel bends and slightly larger diameter. flowmasters are designed for sound, not for power or flow. also, welding them on might add restriction if not welded right

 

[rio95]

trust me, get a cat-back not just mufflers. I had weld ins and they rusted so bad at the welds that they fell off 2 years down the road and then i ending uping haveing to buy a whole cat back.

p.s. It was the previous owner that did the first muffler swap. I would have known better to do the whole cat-back.

 

[jdetten]

get some spintech prostreets

 

[cadde300]

if it were me and I had to do it again I would just buy muffs again. If you are worried about rust then, after the muffs are welded in, put carboard between the muffs and the car.....after that spray hi temp paint, silver, on them and all over the new welds. Do alot of light coats.....= no rust. By the way, all aluminum mufflers are going to rust wether in a catback or not. Flowmasters are the worst. They dont' last long. I have spintechs and I painted mine before I had them welded in and I will paint the welds in the near future, when I get off of my lazy ass. This will delay the rusting process, not sure how long though. I'll find out...haha

 

[Blue Mach]

I went with the Borla’s (they do cost more). They are not as loud as some brands you will see a performance and mileage difference. Add a Bassani X pipe and you have a sweet sounding Stang.

 

[edcar01gt]

get some spintech prostreets

ditto....you'll love the sound.....then get yourself an o/r x.... ....you'll make your neighbors deaf......

 

[XStanger]

so the gas mileage improvement is my biggest concern

If that is your biggest concern, you may want to think twice about it! You may actually get worse milage, because you will find yourself throttle happy.

 

[darkstar]

i have an off road x withs spintech prostreets dumped. i cant hear too well anymore but i love em

 

[01GT eibach]

Agreed with the above:
1) Go catback instead of weld-in mufflers (the ONLY reason to get weld-in mufflers is because your heart is set on a particular set of mufflers not available in a catback ... IMO).
2) Your gas mileage will go up, but likely VERY little (assuming it is even measurable). It likely will not go up enough to offset how much gas you could have bought with the money you paid to get the mufflers installed. That being said, the stock restrictive mufflers should absolutely be ripped out.

 

[95five-oh]

bassani/flows

I've been running welded-in flowmaster 40's with a bassani xpipe with cats and stock headers on my car. It sounds pretty good...a nice loud tone when you stomp it but pretty quiet when cruising or idling...flows will sound good on any mustang but of course just about everyone has them. If you just want to buy a catback but want it to sound beast, get an SLP loudmouth...

 

[white-04]

Holy thread resurrection....