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Exhaust on this car is hard..

Messages
181
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140
Location
Dunmore, PA, USA
#1
Okay, I'm getting desperate here. I'll try to keep this short and sweet. I'm catless, x47r, AWR 62a upper mounts, AWR 88a lower mount and Whoosh poly hanger bushings (I mention these for a reason..). It may be obvious, but I also have no sound symposer. So far, I've tried the below catbacks:
  • MBRP
    • Car sounded incredible but drone in the 3k range was horrid, especially with the AWR upper mounts
      • My AWR upper mounts at this time were 70a and WAY too stiff even after "break-in" of 2k+ miles
      • SOLD
  • Thermal R&D
    • Car sounded great still besides losing the turbo whistle that made the car sound like a tractor lol
      • The drone was bad with this until I realized the 70a AWR mounts were the problem
      • Switched AWR upper mounts to 62a and now I can't hear the exhaust. It's practically pitch quiet til I get on it which is both good and bad. Just not what I'm looking for.
  • CPE Nexus (with resonator)
    • Car sounds amazing. No cool turbo tractor sounds, but sounds a little more unique compared to the other two catbacks.
      • Between every shift over 2k, alongside the RPM drop, there's a "whooooom" sound that neither exhaust had
      • From like 2800-3500k the loudness factor goes from 0-100. It's not quite "drone" but just LOUDNESS that almost sounds fake/engineered. Hard to explain.
      • Cruising at 65-70mph, it's just a hair too loud. I also wouldn't call this drone, but just overall volume.
So okay, the point of all that explanation comes my questions:
  • Is it at all possible the poly exhaust hanger bushings are causing loads of noise being transferred to the cabin? Reason I ask is, my MBRP was on stock hangers and ONLY was too loud when it was in the drone range or when I was getting on the car. I swear the CPE is somehow louder more often than the MBRP was.
  • Has anyone modified the Nexus as in adding perhaps a small muffler to it? I'm afraid to do this as I don't want to totally kill the sound, although I think this is a good option.
  • Lastly, who has found the best 3" exhaust setup for this car? I'm having a hell of a time with this finding the perfect blend of noise and least drone possible.
    • While it's not the most comparable car in terms of construction, my mk5 and mk6 GTI both had turbobacks that sounded absolutely incredible at every RPM with no drone. I'm chasing that but I think GTI >>>>>> Fiesta ST in terms of overall interior/parts quality and that's a big difference.
I know this is long winded but I'm hoping for some good discussion. In two days I'll be swapping to stock-like rubber exhaust hanger bushings to see what that does. Also, for what it's worth, I didn't feel any contact points where the Nexus is hitting the underbody, but I will be double checking that as well.

In the end, what I’m looking for is an exhaust that simply makes consistent noise throughout the RPM range without all the harsh “boomy-ness” or drone. There’s just something about this car that doesn’t allow that to happen compared to the several other great sounding cars I’ve owned. Perhaps it requires a combo of something I haven’t tried yet..hopefully.
 


Last edited:
Messages
40
Likes
68
Location
Kalamazoo, MI, USA
#2
In for the Thermal R & D partout. ;)

I'm, unfortunately, too new to the platform to be of much help. From everything I've read, the Thermal seems to be the "sweet spot" for most people. You're one of the first I heard that didn't like it.
 


OP
blongo804
Messages
181
Likes
140
Location
Dunmore, PA, USA
Thread Starter #4
In for the Thermal R & D partout. ;)

I'm, unfortunately, too new to the platform to be of much help. From everything I've read, the Thermal seems to be the "sweet spot" for most people. You're one of the first I heard that didn't like it.
I’d hate to say I didn’t like the Thermal. More so, I just bought the Thermal as a bandaid for hard spec mounts that I didn’t realize were the issue. Now that I fixed the mount issue, the Thermal is WAY too quiet for what I’m looking for. It’s a great quality exhaust but just way too muffled for me.

I want sound but also want ear drums!
 


dhminer

2000 Post Club
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2,577
Location
Burlington, NC, USA
#6
I’ve had a few combinations. Catted and catless, stock turbo, big turbo, tubular manifold, 3” downpipe to 2.5” cat back, full 3”, etc. FWIW I don’t notice much of a difference in total volume with a catted or catless downpipe.

The best sound I’ve gotten out of this car was with tubular manifold, catless downpipe, Cobb cat back. I think the Cobb was really the difference maker. It was the perfect volume and tone. Wish they’d make a 3”
 


Messages
297
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Location
Broken Arrow
#7
OP
blongo804
Messages
181
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140
Location
Dunmore, PA, USA
Thread Starter #8
I have an s280 turbo with a catless DP and milltek (non resonator) catback and I really enjoy it. It is noticeable driving around town and naturally comes alive when the turbo gets to business. I'll attach a couple videos.

View: https://youtu.be/vNuEj-JoTKs


Drag strip passes

View: https://youtu.be/K5NZ1iApGI4


Inside noise windows down

View: https://youtu.be/YJzFByhFL_Y


Inside noise windows up

View: https://youtu.be/eoABfrr5R4U
Thank you for the videos and for your thoughts!

I think I originally dismissed this catback because it’s not 3” but at this point I think I’d be willing to sacrifice a quarter inch of piping for some sanity lol.

Questions - will this mate up fine to a 3” downpipe? Would I still use a 3” gasket?

I’ll be swapping in rubber hanger bushings tomorrow to see if I get any interior relief from my Nexus but will definitely be considering this Milltek in the meantime. Thanks again!
 


Messages
297
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660
Location
Broken Arrow
#9
Thank you for the videos and for your thoughts!

I think I originally dismissed this catback because it’s not 3” but at this point I think I’d be willing to sacrifice a quarter inch of piping for some sanity lol.

Questions - will this mate up fine to a 3” downpipe? Would I still use a 3” gasket?

I’ll be swapping in rubber hanger bushings tomorrow to see if I get any interior relief from my Nexus but will definitely be considering this Milltek in the meantime. Thanks again!
Yes, I have a 3" downpipe and I believe a 3" gasket is used as well. I have lots more videos on my youtube if you want to check it out!
 


OP
blongo804
Messages
181
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140
Location
Dunmore, PA, USA
Thread Starter #11
Yes, I have a 3" downpipe and I believe a 3" gasket is used as well. I have lots more videos on my youtube if you want to check it out!
Awesome. I really appreciate the insight! It sounds like Milltek is a solid bet. We'll see how it goes when I swap to softer hanger bushings tomorrow. :LOL:
Put on a catted downpipe or install a resonator.
Catted downpipe is technically an option I guess. I don't think a second resonator will do the trick unfortunately.
 


gtx3076

1000 Post Club
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1,358
Location
US
#12
Awesome. I really appreciate the insight! It sounds like Milltek is a solid bet. We'll see how it goes when I swap to softer hanger bushings tomorrow. :LOL:

Catted downpipe is technically an option I guess. I don't think a second resonator will do the trick unfortunately.
Plenty of companies offer them. Ultimate-racing has a high flow metal cat.
 


Messages
153
Likes
102
Location
Woodbridge, VA, USA
#13
I have the MBRP and couldn't stand the drone (gave me headaches on the way to work).. I had an exhaust shop weld the old muffler on the back and it totally fixed it, still really loud but no drone anymore. Not sure what exhaust the previous owner had installed but the muffler is good. I have Whoosh hangers from Cat to muffler
 


M-Sport fan

9000 Post Club
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Location
Princeton, N.J.
#14
The Nexus has been on my car for about 5.5 years now, and is the only aftermarket system I've ever owned/installed on this car.

It sounds perfect to me, but then I still have the factory snail and down pipe on the car, and will until it goes bad on me.

I have the Whoosh hangers and the ONLY time it ever gets 'boomy' on me is when I lug it a bit, and try to bring the revs up too quickly in too high a gear.

The only idiosyncrasy/oddity I have noticed with this system is a low 'pop' out of the exhaust (factory tune as well) in between easy, lower rev upshifts, which I account to the 3" diameter system on factory turbo thing.

Not the biggest fan of the textured 'shot blasted' finish of this system, and would have preferred the smooth satin stainless look finish of the Thermal, but other than that (and the high mounted, back Helmholtz resonator getting in the way of one of my custom exhaust tips), I really like this system a lot.
 


jeffreylyon

1000 Post Club
Premium Account
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1,110
Location
Pittsburgh
#16
Coincidentally, I'm about 30 miles into a Whoosh catted DP and bushings and the Thermal exhaust and I'm in love (poly insert in the motor mounts). The back of my car is semi-stripped so that contributing to the volume, which is probably louder that I'd normally want on a street car, but the tone is perfect and reminds me of my Mk1 Fiesta with a SuperTrapp "muffler" and a stock-compression engine.

So far I not hearing any drone but this is my track car and sees very little highway time, so I don't know that I'd notice. My guess is that a catted DP makes a big difference as it may act as an upstream resonator.
 


Messages
164
Likes
214
Location
Knebworth, UK
#18
OOI is it drone from the pipe or resonance from the boot floor - Ford weren't exactly generous with sound damping ..... i'd also bet the poly bushes aren't great at preventing NVH transmission sadly.
 


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