ieditsports

I know there has been a lot of talk on this. I was just wondering if the V6 would benefit from dual exaust or would single be better for the car?? I will be upgrading soon and was leaning towards the single mangnaflow. Also if you go to there web site you can hear the mustang V6 with 3 different audio files. Pretty cool. Thanks

Fazm

Testing has shown that there is no gain from going dual instead of single on a stock v6. If you had some kind of forced induction im sure that dual would definately be beneficial.

scrming

As other poster said, no benefit from dual... I just put that EXACT Magnaflow single your talking about on my car last week! It sounds really good! Looks good too! I was in a V6 yesterday that the dealer had put GT duals on... My Magnaflow definitly sounded way better!

ieditsports

Thanks, that's what I thought. Magnaflows it is!! If they sound as good as they do on their web site it will be a great upgrade!

scrming

I don't think you'll be disappointed!

I need to take the video camera out and get a good clip of my car going buy at WOT! LOL!

xxkazp3rxx

Hey guys correct me if im wrong, but I looked underneath my V6, and it is duals coming off the header, just a Y Pipe, leading to a single exhaust pipe, so I would think if you're going to be putting any type of performance on your mustang, even if it's a V6. It would sound better, and give some performance boost if you went with maybe a X or a H pipe, as long as you didn't put to wide of pipes on it, wouldn't it?

I think most of the people with aftermarket dual exhaust's problem is, is that they're using to wide of piping causing some pressure to be lost.

Fazm

Im sure you could put an xpipe and then go with smaller exhaust piping, but that would really limit your future mods. If you are going to go dual with an x or hpipe, wait until you need it.

xxkazp3rxx

Well the actually piping is either 2" or 2 1/4" from what it looks like. The Xpipe at the same size wouldn't limit you to much, you're only going to get so much pressure out of the engine. Anyhow, there is dual exhaust coming off the header, just converted into one pipe.

Does anyone know the actual piping size for the stock v6? I just have a hardtime believing as long as you don't put 3" piping on there, that you won't gain any power and won't sound as good as the single exhaust.

Fazm

Its not a matter of believing us or not. i believe it was mac that stated that they got both 9rwhp from a single and a dual exhaust, not to mention the sound was better and it would cost less to produce and sell.

DanteMO

I have to agree with Fazm... If anything, a true dual will cause some hp loss. I have a dual flowmasters with h-pipe on my v6. I think (this is a guess and I have no dyno's to prove it) that I've lost a little at the low end.

As for the sound, I have to disagree with you all there. "Better" is a subjective term and you could probably poll 10 people and get different terms for what "better" means when it comes to the sound. I love the sound on mine with duals but others might not. Only YOU can determine what's "better" when it comes to that.

And for me, it was also cosmetic. I like the look of two pipes coming out the back of the car. It was 400 bucks to get it done. But only you can determine if that's a good investment or not. But be warned, those who have gone dual and had problems with their gas tank (TSB on that) stopping and not filling up have taken it back to the dealer only to have the dealer say that they would have to hack up their exhaust to replace the gas tank

Good Luck whichever route you go!!

ManEHawke

For the displacemant & hp it's ideal to have the stock 2 1/2 Y, or duals at 2" or maybe even 2 1/4.
A supercharger would improve volumetric efficiency so you gotta take out what you put in. Here duals at 2.5 would be ideal. So like everyone else I'm going to wait untill I need if it comes to that point.
I sure love the look of duals, and is a shame there is not kit for duals at 2". Maybe later I may be brave to get one custom

xxkazp3rxx

well it's not whether or not im believing anyone on this board, I didn't want it to sound like that... It's just hard to believe period, although a Dyno is a Dyno. Now, since there are no emission checks here, a lot of people take off thier cats... I have an actual Mustang I am modeling after because i've seen these things work on thier cars, which were V6 Mustangs, in 2001, 2004 and a 2005. But what do you guys think about deleting those cats? Also, I have the Steeda CAI which according to Steeda boasts up 16-20 Rear Wheel HP (steeda.com), with the Xcal which is said to put around 20 ponies or so in there, with 3.73 gearing, and deleted converters which Mustang performance shops said will give me extra hp as well with the exhaust, you think that going to that Xpipe at around the 2 1/4" would hurt the performance?

Fazm

more air in, more air out = more power. Most people are seein gaines of 13-15hp with the CAI and a tune. exhaust will probably add around 10 more at the most. So you can see a hopeful 25hp gained from intake, tune, and exhaust.

about taking off the cats, i dont know how that will effect hp because they might play a significant role in backpressure which might kill your low end power.

xxkazp3rxx

As far as the CAI power increase, Steeda is boasting that rear wheel HP had that gain, so... who really knows, next to the dyno... Now, I know I raced a 2005 Mustang with the MMR kit, and we were nose to nose, till about 3rd gear when I pulled on him by about 3/4 car. I know it impressed him because the next week he sold the MMR and bought the Steeda and we raced and we're nose to nose the whole way unless one of us gets a bad shift or launch. As far as the cats go, I know they increase power, as i've drivin a mustang before and right after - just not sure how much actual HP - i've heard 15-25 at the fly, but thats hearsay. I just do a lot of reading before I buy anything, and I see the Tuner without anything else boats 20ponies and the CAI boasts that much once it's tuned. Now wouldn't that be atleast 20+26 = 36 extra? Which would put me at 246 @ the flywheel. Adding the approx 9 hp from either exhaust side leaves me with 254 at the flywheel. With the gearing which puts more combustibles in the engine creating more back pressure in addition to the hp increases, wouldn't that be enough to warrant the X, H or straight duals?

I just always go back to my good friends 2001; that had basically everything done to it that I am, and he never lost any power. Even when he put in headers, which I thought might not be the best idea for a 3.8 V6, but his car was darn fast for a non-forced induction V6.

As far as my math problem above goes... how off would you suspect I am with these numbers? I do believe companies inflate numbers to increase sales, seeing how I use to sell Fords - but they can't be that off, can they?

ManEHawke

I heard this from an experienced tech, who's been in the field for over 30yrs.
As a rule of thumb for duals you have 200hp and 2" piping. For every 50 hp you add increase piping .25". It made sense because at 300 hp the GT uses 2.5 duals. Many 400hp cars use 3" duals. So seeing what engineers use it makes total sense to me. They all can't be wrong.
So for our stock it'd be good to be at 2" duals. At a modded V6 at 250 hp it'd be good to be at 2.25. At a really modded V6 (possibly FI) at 300hp duals at 2.5 would be good.

Fazm

The cai tuned is worth 20hp, not in adition to the tune. it is more like 13hp from the cai, and 7 form the tune, to get a total of 20. And last i checked 20+26 was 46 not 36. Most gt owners arent even seeing more than 20-25hp from CAI and tune, nevermind with the v6. The exhaust claim of 9rwhp may or may not have been on a car with CAI, thats hard to find out. I would say at most you would get 30rwhp from tune, intake, and exhaust.

ManEHawke

It also depends on dispacement, but the above is correct with our 245 ci engines.

Zodiac

Phew, headache reading all these numbers and stuff.

Gutting out the cats will produce a louder sound definitely. At MOST it might net you 5hp. You are, however, going to open up the exhaust and reduce backpressure. As a result, you could even end up loosing horsepower.

Its hard to say you're going to lose hp based on simply going duals. Its going to depend on mid pipe, placement thereof, and muffler deisgn, as well as pipe sizing. Flowmaster reccomended 2.25" pipes for duals at 200hp. I ended up going with 2.5" to save cost on more pipes, and having room to expand later. If you're going to a more restrictive muffler, or add resonaters in to increase backpressure, I really doubt you're going to see any loss in performance. You might lose low end torque, which is what you feel off the line, but gain it in the high end. Again, that refers mostly to the midpipe and its placement.

You also have to factor in then the additional benefit of having an aftermarket intake, especially when talking about backpressure. If you're flowing more air, with more airspace behind it.. see what Im getting at? It could increase, decrease, God knows... there are so many variables in this.

Gut the cats, and run a reverse Ypipe. I doubt you're going to see any HP loss at all. Run it with a CAI and Ill bet you see a gain. Add in resonators and gut the cats, and I bet you see a gain still. But what do I know?

xxkazp3rxx

haha yeah, sorry about the math.. been a long day. Well what everyone says on here, while a little bit contradicting does make a lot of sense. As far as that goes, there is a guy that has worked on Mustangs for about 25 years now, and i'll just go with what he says, I know he won't be ripping me off, because he's not the one doing the work, but i'll let you guys know what I end up doing and what the dyno says after all the work. Thanks for all the great input.

1trickpony

About the cats, Kenne Bell claims you'll lose 10 HP for a 300 HP engine. Based on this,a GT will probably gain 10 HP without cats. I saw a dyno showing 8 HP, sounds about right. This isn't linear, so I think Zodiac is right, the V6 might get 5 HP from losing the cats. About Steeda, I bet that filter gets you maybe 5-7 HP, the rest is tune. Magnaflow says a single exhaust is better for stock engines. Its listed under frequently asked questions. Duals are better for heavily modded engines. A Lincoln Aviator runs a single 2.5" with a 300 HP V8, the same size as the 4.0L. The exhaust sizes for engines are listed at Mangaflowand match what ManEHawke said. Mangaflow claims the same power increase for their dual and single exhaust systems. Run a search for Mangaflow on this site, Brent from Mangaflow provided a lot of good info on this subject.