3 gen dual exhaust

[DFendersExpy]

has anyone done a true dual exhaust one a 3 Gen?

 

[Snag]

Its been the general consensus that IRS on these rigs make it very difficult. When I was under mine doing the fluid changes and rear main seal I looked at possibilities of a better sounding exhaust. At a glance I would say a dual in and single out would be doable. Ford ran good sized exhaust pipe on the exhaust manifolds but the drivers side one where it welds into the muffler is smashed oval and about half flat. The passenger side one is nice all the way back to the muffler. It wouldn't take much for a "good" muffler shop to cut the drivers side back 10"-12" create a new radius bend and into a "dual in" nice performance muffler. Then make a new mandrel bent 3" going out. All the performance muffler manufacturer's make dual in and single out configurations.
But it would never sound like true dual's. Well and even true dual's need a cross over pipe for optimum performance.
The only other option I could see was stubbies dropping out just in front of the rear tires. But most Expeditions seem to have running boards of some kind so would be difficult.

Go to a good muffler shop, they can give you prices and options. I would stay away from any ebay clamp ones, they tend to be cheesy. I put one on my Heep Wrangler and had to refab it to work properly.

Good luck, tell us what you find

 

[mtrebuchon]

Post 1 of 2

I did it to my 2014 Expy. Pics are below but please excuse the quality. She's lowered 3/4 so it was very hard to get good angles (don't ask me why I didn't take pics when the system was being installed...duh duh duh), but you can see the general path.

Pic #1 is the X-Pipe
Pic #2 is the inlets to the Flowmaster 50 series
Pic #3 is exiting the Flows and turning up towards the floorboard (see torque arm)
Pic #4 is two pipes coming up over the cross member by the spare tire (tire guard removed)
Pic #5 different angle of pic #4

See Post 2 of 2

 

[mtrebuchon]

Post 2 of 2

Pic #6 is the down sweep from the floor board (see spare tire in upper left corner)
Pic #7 is the exit path

The only mod to the vehicle to make it work is the removal of the fiberglass shield around the spare tire. As is, there is 4 1/2" of clearance between the inboard pipe and the spare tire. The system has been installed since September of 2014 and there is no damage to the spare tire what's so ever.

 

[montecarlo31]

That system looks interesting but any gain is lost with the crimped exhaust bends. Mandrel is the way to for exhaust systems. Unfortunately Corsa does not make a system for the expedition but Magnaflow does make a single system which is well designed and thought out with what appears to be proven dyno gains (trying to find the dyno charts now). https://www.magnaflow.com/products?partNumber=16379

Edit this is a single exhaust, the 5.4 is no where near making enough power to max out a 3" mandrel bent exhaust system.

 

[mtrebuchon]

A 3.0" ID true dual set up even with crush bends (usually -0.15") will way out flow any single system of comparable size, mandrel or not...that is basic physicis. The maximum volume of one 3.0" ID pipe is 52.6% less then two 2.85" ID pipes (taking into account crush bends), with all other things being equal. Surely two Flowmaster 50 Series flow as good as if not better than one Magnaflow MF. Not to mention, the Magnaflow system is a pathetic example of a "cat-back" because it uses the factory Y pipe which measures anywhere from 2.41" - 2.68" ID (depending where you measure) along with its two crap bends (left side 84 degree crossover and the oval prior to the Y).

I will guarantee that a twin-screw 5.4 3V running 12 psi will max out the single 3.0".

 

[buzzie0013]

MTREBUCHN, this is exactly what I was thinking of Odin to my 2013 el. what improvements in performance have you seen?

 

[mtrebuchon]

It's really kind of hard to tell because I added a Saleen Series VI Supercharger and reworked heads at the same time. However, with the Flowmaster 50's running 12 lbs of boost the dyno gave her 502 RWHP and 519 Lb/Ft of Torque at 5,050 RPM. This at least tells me she's breathing well at both ends. The best part of the FM 50's is the super deep rumble when my foots in her (even over the twin-screw whine) but very mellow when driving normal.

 

[GalaxyPilot]

View attachment 19058 It's really kind of hard to tell because I added a Saleen Series VI Supercharger and reworked heads at the same time. However, with the Flowmaster 50's running 12 lbs of boost the dyno gave her 502 RWHP and 519 Lb/Ft of Torque at 5,050 RPM. This at least tells me she's breathing well at both ends. The best part of the FM 50's is the super deep rumble when my foots in her (even over the twin-screw whine) but very mellow when driving normal.

On a 3d gen expy, that is nuts! Hats off to you man for getting all that in there

 

[mtrebuchon]

Fit like a glove (better than OJ's). It was fun reworking the EVAP, cooling and vacuum systems! It took a good month to work through the P1451 EVAP code and the P1712 & P1749 Torque Reduction & Trans Pressure codes. The 6R80 does not take to rapid torque increases. It's plenty strong enough, it just doesn't process the instant increases created with boost. But, with excessive data logging, trial and error with shift tables and pressures, she came through!