MDesign Race Spec Prototype Exhaust

[MDesign Performance]

Decided to make a new thread for this specifically to take suggestions/comments/and show results concerning the exhaust.

Exhaust installed, MDesign Race Spec Prototype 1. Uses 2.5" piping which split to a single 3" piping then back to dual 2.5" at the rear, all stainless free-flow mufflers.

Pros: Increased power/quicker spool, better gas mileage, and now gurgles when you blip the throttle, sounds beautiful downshifting

Cons: Drone in 1800-2500RPM

Performance gains are confirmed via SCT X4 tuner. Under cruising and slight blipping of the throttle (1000-2000 RPM range) most of the time I am at -10 vacuum up to 0psi pre exhaust, post exhaust I now hit 2psi doing the same thing. Also I spin the tires effortlessly now, whether it's from a dig or roll on 1-2 and 2-3 shifts. While there is no rasp whatsoever and no drone in other RPM, the drone that is only noticeable in the 1800-2500 RPM range is a bit much to my liking therefore I'm willing to sacrifice some performance for sound reduction.

As of now I am contemplating using an oval shaped resonator up front which should eliminate drone considering the system is completely free-flowing, though am not sure if I want to stick with the original design (JimiJack's dual inlet/outlet resonator) or a wider and larger volume single in/out.





Here is a quick video, rattling is the phone in it's make shift temporary cup holder not the exhaust!

[FoMoCoSHO]

I'm very excited about this exhaust, not so much with any drone. I will be paying close attention to this thread and how the drone issue progresses.

[MDesign Performance]

I'm very excited about this exhaust, not so much with any drone. I will be paying close attention to this thread and how the drone issue progresses.

A more efficient resonator should kill the drone since it is only at the low end, cruising in 4th gear at 70MPH put me at 3-3500 RPM and the car had 0 drone, sounded as quiet as stock.

[SHODYOU]

Yea you could go next size up in midmuffler, but itll come with internal x.
I had it, 14" version and had no rasp or drone with dynomax UltraFlo's.

[crash712us]

Interesting sound, look forward to hear in person some day.

[MDesign Performance]

Yea you could go next size up in midmuffler, but itll come with internal x.
I had it, 14" version and had no rasp or drone with dynomax UltraFlo's.

There's actually a single 4" race style mid muffler instead of a dual in/out, I went ahead and ordered a larger oval shaped mid muffler that should definitely kill drone so we'll see what happens when that gets in.

Interesting sound, look forward to hear in person some day.

I'm only 10-15 min away from you in Dearborn, even closer when Im at LA Fitness in Allen Park. I'll be free all day tomorrow if you want to see what it sounds like, would love to compare it to your Corsa side by side! Sent you a PM.

[MDesign Performance]

Quick video from last night, going to need good speakers and the volume raised!

http://youtu.be/zwpsuyQnwFI

[MDesign Performance]

Quick video from last night of very low revs, going to need good speakers and the volume raised!

http://youtu.be/zwpsuyQnwFI

[panther427]

Sounds real nice got a bunch more rumble than the first design

[BiGMaC]

Sounds good... I love the rumble too!... I'm interested to see if the change gets rid of the rasp you notice in the 1800-2500 (cruising range)....

Any dyno numbers? stock vs MDesign?

[MDesign Performance]

Sounds good... I love the rumble too!... I'm interested to see if the change gets rid of the rasp you notice in the 1800-2500 (cruising range)....

Any dyno numbers? stock vs MDesign?

It's not even rasp, from outside it sounds completely fine. The reason there is any drone from the cruising/engine load range is due to the 3" mid section. You gotta see it in person to respect the 3" piping difference, and that is causing resonance inside the cabin only.

That is the only "issue" as of now and I believe this new resonator modification will fix that. I put issue in parenthesis as I don't believe it really is one, this car pulls and breath much more easier and the power gains are there.

You kinda have to respect it for what it is, a race oriented catback system.

[Wilson]

Keeping a close eye on this.  If you can keep that sound while getting rid of the 1800-2500 drone, I'm sold.

[MeanKS]

that is the best exhaust note i've heard from any transverse EB application!

subpar exhaust note is just one of the few negatives that i thought was inevitable with the 3.5EB, although Ford did a much better job with it in the 2.0EB in the Focus ST.

once you get that drone/rasp fixed, I don't see how it can be improved much more.

Great job!

if you can provide a cost work up, including install, that would be great...

[MDesign Performance]

that is the best exhaust note i've heard from any transverse EB application!

subpar exhaust note is just one of the few negatives that i thought was inevitable with the 3.5EB, although Ford did a much better job with it in the 2.0EB in the Focus ST.

once you get that drone/rasp fixed, I don't see how it can be improved much more.

Great job!

if you can provide a cost work up, including install, that would be great...

Thanks! I've been trying to get miles on it to get some carbon build up inside the race style mufflers to see if it improves after some break in and it is, though the drone/hum is still there. The exhaust note is also improving over time to a nice purr, it's really hard to explain and capture it on video due to the bass.

Regarding install this will bolt up to the factory downpipes, and install will include 3 or 4 clamps to piece the system up which is for shipping purposes. Anybody with a jack and basic tools should be able to get it done in a hour or so.

[panther427]

Thanks for your ideas and work. I had really not planned to buy an exhaust until you realised this dream.  When you gonna talk about your intake?