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  • 2005 - 2014 S-197 Mustang -General/Talk-
  • 2005 - 2014 Specific V6 Tech

exhaust help

  • Thread starter Thread starter red05v6stang
  • Start date Start date Sep 17, 2005

red05v6stang

New Member
Sep 10, 2005
116
1
0
Sep 17, 2005
#1
  • Sep 17, 2005
  • #1
alright guys, i didn't want to take away from the exhaust thread started already. my question is, would it be smart going to 3 inch piping? im thinking a 3 inch x pipe and the 3 inch 40 series mufflers. would this cause problems with heat on certain parts under the car compared to the readily available 2.5 inch parts? is it a whole lot cheaper to run the 2.5? If I do this, I will probably run the cobra cats just because they will open it up a little more, any problems there? what should i look to as a ballpark figure on this? for 3 inch and for 2.5. form the videos i have seen the exhaust sounds good, but i want a really low tone. any help is appreciated. maybe i can run cobra cats, gt pipes, and that x pipe yall are talkin about with some 40 series mufflers, or is there a better muffler for a low tone?
 

rygenstormlocke

former 10 second badass
Aug 13, 2005
698
0
0
Northern Virginia
Sep 17, 2005
#2
  • Sep 17, 2005
  • #2
I'm not an expert and still learning, but I have been reading the exhaust threads extensively. Everything I read says the 3 inch pipe conversion is not worth it. Leave the 2.5 and go with a H or X pipe to get the lower tone. I also heard that headers help the sound tremendously. MSP and Afixer have good setups, check with them. I'm running 2.5 pipes with magnaflows and now looking at a MAC power chamber. Also, if you can afford the cobra high flow cats get them, I hear great things on these conversions.

Given all this I would check with some of the other people on this forum, they are more subject matter experts and I can't speak from expereince cause I am still working on my exhaust.

Check the "hey msp i got exhaust parts" thread. Ton of good info there.

Good Luck.
 
Z

Zodiac

New Member
Dec 17, 2004
247
0
0
Sep 17, 2005
#3
  • Sep 17, 2005
  • #3
3" pipes are too big on the GT unless they're blown and running ridiclious power levels...

2.5" on the v6 is perfect imo. Its a tad wide for stock, but if you plan on doing ANY kind of performance mod its perfect -youll never need to go any bigger. 3" is just too too wide, not enough backpressure and velocity.
 

red05v6stang

New Member
Sep 10, 2005
116
1
0
Sep 17, 2005
#4
  • Sep 17, 2005
  • #4
is the stock pipe 2.5? where i would only need to buy the driver side gt pipe? i think thats my understanding as to how others did it as well. also, how do u get from the heades to the x-pipe? custom bent tubing or what?
 

fazm83

New Member
Apr 8, 2005
747
0
0
phoenix, arizona
Sep 17, 2005
#5
  • Sep 17, 2005
  • #5
3" is what is on my cobra lol, and even that is a lil on the large side. i think the stock is 2.25" but im not sure, ask around people will know. Im going to be leavin my exhaust alone for now, until these kits drop in price.
 

rygenstormlocke

former 10 second badass
Aug 13, 2005
698
0
0
Northern Virginia
Sep 17, 2005
#6
  • Sep 17, 2005
  • #6
Yes, our cars are 2.5 in piping, same for the new GT's. It's an increase from 2.25 last years model.
 

fazm83

New Member
Apr 8, 2005
747
0
0
phoenix, arizona
Sep 17, 2005
#7
  • Sep 17, 2005
  • #7
Well there ya go, told ya someone would know lol
 

rygenstormlocke

former 10 second badass
Aug 13, 2005
698
0
0
Northern Virginia
Sep 17, 2005
#8
  • Sep 17, 2005
  • #8
Yep, I jacked mine up and got out the tape measure...and looked it up. What I love about our 4.0's is they are just like the GT's, dual cats underneith so going true duals isn't difficult. When I first got mine someone told me I have a single CAT, that is when I jacked it up to know what I'm dealing with.

Good luck!
 

fazm83

New Member
Apr 8, 2005
747
0
0
phoenix, arizona
Sep 17, 2005
#9
  • Sep 17, 2005
  • #9
i dont think any OBDII cars have single cats if they run more than 1 bank. Even some single bank cars run more than 1 cat.
 

afixer

The Informant
Apr 3, 2005
380
0
0
Sep 17, 2005
#10
  • Sep 17, 2005
  • #10
yep 2.5 is just fine order the left pipe from ford and the brackets get an x pipe and the gt takeoffs and for about 450.00 total your all good
 

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rygenstormlocke

former 10 second badass
Aug 13, 2005
698
0
0
Northern Virginia
Sep 17, 2005
#11
  • Sep 17, 2005
  • #11
Afixer, that picture is just beautiful. Well done!!!!!!
 

Chris_NY

New Member
Jun 9, 2005
48
0
0
Sep 17, 2005
#12
  • Sep 17, 2005
  • #12
IMO 3" will probably actually be detrimental .. I mean performance will be less then with 2.5..

When they designed the car they chose 2.5 because the gasses flowing through the pipes will flow at the most optimum speed for the best performance..

When you go duals you are already in essence doubling the area that the gasses have to travel in.. and that will reduce this Exhaust gas velocity ..

Then adding another .5" to the mix and you can see where this is going ..

So if you go 3" duals you better have something compensating for that extra pipe area in the back by having more air going in at the front .. meaning High flow intakes .. or Forced Induction of sorts .. to balance this equation out..

But thats just my 2 cents.. I am no scientist or engineer I am just a hobbyist..

personally I went 2.5" true duals and I got a very nice increase in pep ...but I've never dyno'd my car so thats just my guess.
 
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