[Rhino77]

Hello all, I have been reading through many of the threads in the v6 tech section, and found them extremely informative. The particular concern that I have I did not find, so I would appreciate some perspective on my questions.

I was speaking with a local shop out here in San Bernardino, explaining that I am looking for magnaflow duals, with an H pipe.
The owner's concern was the issue of back pressure, and that with the cutting of the Y pipe, the back pressure would be lacking and that gas mileage would drop.

1) Is this a legitimate concern?
2)Will the gas mileage drop rather significantly.
3) Would the best route to go, be to keep the Y-pipe with a dual setup behing the Y? If so, will the rumble be as deep/loud?

Thanks guys.

[snake 42]

Cutting the Y pipe will certainly decrease the back pressure as will the addition of dual pipes and high flow mufflers. It has been my experience that the slight loss of low end torque is more than off-set by the improved flow and increased performance above 2000 rpm. I have not personally heard of anyone losing gas mileage as a result of improving exhaust flow. The loss, if any, usually comes from the driver's inability to keep his or her right foot from playing with the throttle. It's rather addictive to listen to the exhaust sound and crave more of it and therefore we tend to get heavy with the loud pedal. One other thing to note is the difference between H pipes and X pipes. I happen to like the raspy note that I get from an X pipe but that is strictly up to the individual. Hope this helps and GOOD LUCK.

[Rhino77]

Originally Posted by snake 42

Cutting the Y pipe will certainly decrease the back pressure as will the addition of dual pipes and high flow mufflers. It has been my experience that the slight loss of low end torque is more than off-set by the improved flow and increased performance above 2000 rpm. I have not personally heard of anyone losing gas mileage as a result of improving exhaust flow. The loss, if any, usually comes from the driver's inability to keep his or her right foot from playing with the throttle. It's rather addictive to listen to the exhaust sound and crave more of it and therefore we tend to get heavy with the loud pedal. One other thing to note is the difference between H pipes and X pipes. I happen to like the raspy note that I get from an X pipe but that is strictly up to the individual. Hope this helps and GOOD LUCK.

Thanks for the quick response.
I just finished talking to another performance exhuast shop out here in the San Bernardino, and it seems as though none of these guys have worked on putting a dual system in a V6.
The fella I just talked said I'd have to come down to his shop to take a look at the system on the car, to have a better idea which is of course is reasonable.

I've got Gibson Performance by me in Corona, Ca and they have develped a dual system specifically for the v6 (part #319007)...Upon further inspection it looks like that part# is dual with an off road x-pipe...Now doesn't off-road require removal of the cat? I just want to cut the Y and stick the dual on after.

This is frustrating not finding a competent exhaust place to speak with, hell, the Route 66 celebration is the in the middle of this city!
(maybe I shouldn't say "competent", but rather an installer that sounds like he knows what he's talking about).

[mrjimmy]

I have a similar set-up. Dual exhausts with the H pipe. Cut the Y out and ran a left side GT pipe back, Dual GT take-offs andJBA Shorty headers. All this before a tune. Gas mileage only fluctuated a bit because I was "on it " more and ,,it was good,,,
I have a Steeda CAI and a performance tune from Jason @ VMP,t-loc and 3:73 gears with LCA's. IT IS BETTER,,,,Just filled the tank today (in Idaho) and after a 3 runs on the strip and some street driving,the usual trips,,I am getting 18 mpg,on 91 octane.
I may be wrong but for the way I have been driving it I think its good.

[scootr68]

I've been to several shops here in Ohio...none here seem to have a clue. Not too stray off topic...Mrjimmy, how much of a difference was it going to the 3.73's? Been contemplating an upgrade to those.

[mrjimmy]

to be completely honest on the 3:73's,,I cant tell much if any. Never went to the track before I had them.The tune did however really make a difference.Now if it is the combination of the two or not I dont know.
The t loc difference is,, now I lay two stips of rubber.
A big difference is the whine in the rear end though,it is noticeable and even sound deadener doesnt help much.I kept the ols set up in case I ever sell it,cause if I test drove a car where the gears howled that much I wouldnt buy it.
Putting an aluminium shaft on this week to see how it goes also.

[SOHCman]

Originally Posted by Rhino77

Hello all, I have been reading through many of the threads in the v6 tech section, and found them extremely informative. The particular concern that I have I did not find, so I would appreciate some perspective on my questions.

I was speaking with a local shop out here in San Bernardino, explaining that I am looking for magnaflow duals, with an H pipe.
The owner's concern was the issue of back pressure, and that with the cutting of the Y pipe, the back pressure would be lacking and that gas mileage would drop.

1) Is this a legitimate concern?
2)Will the gas mileage drop rather significantly.
3) Would the best route to go, be to keep the Y-pipe with a dual setup behing the Y? If so, will the rumble be as deep/loud?

Thanks guys.

From seeing everyones reply, we can safely tell you "Don't go to a muffler shop". They don't have a clue.

I had my Ford dealer do the job.

1) No
2) No. (mine went UP by 2 MPG)
3) No. No.

Go full duals (you're already spending the $$).

Pypes has the SFM-68 (full system) and SFM-65 (add your own mufflers).

Here are my true duals with Pypes Street Pro mufflers.

2006 Mustang V6 Pypes Duals Getting on Highway - Putfile - Upload and Share Your Videos

SOHCman Pypes Acceleration - Putfile - Upload and Share Your Videos

Ford's V6 package comes with an "X" pipe, like the Pypes setup.

It's a V6, I really don't think "X" or "H" will make much difference.

SOHC

[Bnuts]

Originally Posted by mrjimmy

I have a similar set-up. Dual exhausts with the H pipe. Cut the Y out and ran a left side GT pipe back, Dual GT take-offs andJBA Shorty headers. All this before a tune. Gas mileage only fluctuated a bit because I was "on it " more and ,,it was good,,,
I have a Steeda CAI and a performance tune from Jason @ VMP,t-loc and 3:73 gears with LCA's. IT IS BETTER,,,,Just filled the tank today (in Idaho) and after a 3 runs on the strip and some street driving,the usual trips,,I am getting 18 mpg,on 91 octane.
I may be wrong but for the way I have been driving it I think its good.

dude you are killin your self with fuel. here read this switch to 89 octane
V6 Mustang Bolt-On Test - 5.0 Mustang & Super Fords Magazine
I went from 450 - 500 km per tank on 91 to a little over 600km per tank on 89 octane on a totaly stock 06 v6. really you are doing your self no good with the 91 octane

[jrudolph]

I had a local shop cut into the y and weld on a driver side pipe. I have GT takeoffs. At idle its very quiet. It's only a v6. But driving they sound good. I did notice a drop in my RPM's, down to about 600. Vibrates a little at a stoplight. No real change in mileage. Running 89 octane. I think a flash tune will help my idle problem.

[Rhino77]

Originally Posted by jrudolph

I had a local shop cut into the y and weld on a driver side pipe. I have GT takeoffs. At idle its very quiet. It's only a v6. But driving they sound good. I did notice a drop in my RPM's, down to about 600. Vibrates a little at a stoplight. No real change in mileage. Running 89 octane. I think a flash tune will help my idle problem.

So you just cut the Y and stuck the pipes directly onto the Y-cut? You haven't balanced out the exhaust with the X or H pipe? Could be why you're getting some of the vibration.

My question is, If I cut the Y on my exhaust, and get and X or H pipe, will I need to stick on a cat after the pipes.

I have purchased 2 GT Takeoff mufflers and midpipes, and plan on getting an X pipe. I'm in California, any difference on the # of cats or placement?

[Bnuts]

Originally Posted by jrudolph

I had a local shop cut into the y and weld on a driver side pipe. I have GT takeoffs. At idle its very quiet. It's only a v6. But driving they sound good. I did notice a drop in my RPM's, down to about 600. Vibrates a little at a stoplight. No real change in mileage. Running 89 octane. I think a flash tune will help my idle problem.

I am looking to do this. I got the mid pipes for a case of beer from a guy here in the city. I still need mufflers but you just cut the Y off and added the extra pipe on the drivers?
Are the pipes the same size that you don't need to change both?
What mufflers do you have?

This is the exact situation that I am getting into so if you didn't use an X or H I would love to know cuz thats $ I can just save