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Mountune or Thermal R&D exhaust

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Location
Edgewater, NJ, USA
#1
Hello Everyone,

I am looking into getting an exhaust and need some assistance.

I am not looking to add an exhaust for the purpose of making the vehicle louder. The goal would be for performance enhancements during all RPM and speed ranges. For the exhaust to give the vehicle a better overall sound and make it sound like a performance vehicle during spirited driving but not so much during normal driving. Definitely don’t want any drone noise at all under any driving conditions. Or it being loud or obnoxious.

Also know with induction vehicle the wrong exhaust set up and size can actually negatively effect performance overall and more so in low RPMs and lowers speeds. So certainly want to avoid that also.


Narrowed it down to Mountune or Thermal R&D and would greatly appreciate everyones thoughts, feedback, experience and guidance.
 


TyphoonFiST

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Rich-fizzield
#3
Thermal R& D ....I have it....got it ceramic coated to protect it from the elements. Best exhaust period. No drone....sounds just like stock exhaust at highway speeds. But when you get on it is when it unleashes its full Fantasmagorical Fury!
 


Spork1569

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#4
Both are good My friend Danny has Mountune I have Thermal. Danny said the Thermal would be his second pick after the Mountune. You really can’t go wrong with either. Mountune is 2.75 inch I believe . Thermal is 3 inch.
I'm of the same experience. I heard the mountune in a vid and instantly loved the sound and the fact that its actually pretty quiet for a catback unless you really step on it.

If I did it again I'd probably get the thermal (which has zero drone according to those who have it, mountune kit does drone just a bit it seems at the usual rmp for the FiST, but not really noticeable)

Also the shop did have trouble aligning the tips on the mountune, and it seems I'm not the only one that had the problem of possibly burning my bumper. If installing yourself you'll need better hangers and a way to bend the exhaust mounts into place. The thermal is plug and play besides a certain clamp that occasionally comes loose as far as I've read.
 


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Location
Raleigh
#5
Just want to point out that moving to a bigger exhaust is unlikely to make any more power as it's not a restriction point until you go to a bigger turbo. If your primary concern is performance and not sound then I'd say spend the money on something else.

On the other hand if you just want the car to sound decent, Thermal all the way! (y)
 


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Location
Denver
#6
I had trouble with the Mountune exhaust install. To get perfect tip alignment I had to make custom hangers out of the Mountune Focus RS hangers to drop the muffler and shift it over. I tried the bending method with little success. It was not a fun install. Other then that I love the look and sound. Currently running the Whoosh hangers on the two front hangers to help bring the NHV down. The Mountune hangers are stiff and will give you a louder tone. It’s worth trying the Mountune fiesta hangers up front first. You can always soften it later
 


jeffreylyon

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#7
The only complaint I've ever heard about the Thermal is that the slip join couplers need regular attention or they'll back off enough to leak. You could fix that by having an exhaust shop weld on flange or v-band couplers.
 


CSM

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#8
The only complaint I've ever heard about the Thermal is that the slip join couplers need regular attention or they'll back off enough to leak. You could fix that by having an exhaust shop weld on flange or v-band couplers.
I've had my thermal exhaust for about 15k miles now and no issues yet. I'll crawl under the car over the weekend and will double check the couplers during my oil change
 


jeffreylyon

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#10
I've had my thermal exhaust for about 15k miles now and no issues yet. I'll crawl under the car over the weekend and will double check the couplers during my oil change
I don't have any first-hand, but there's a thread out the Thermal couplers loosening up. Everything else I've heard about the Thermal is very positive and you can't beat the price.
 


TDavis

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#11
I check my slip clamp on my Thermal once every 5-10kish miles.

Don't fret too much about it, its not like it happens every other drive.
 


Mikey456

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#12
The Thermal does give more sound (good sound, mind you). It’s not quiet. I drove behind a car with one. I’ve heard good reviews for the FSwerks exhaust too as another option. There are plenty of YouTube exhaust sound clips for these exhaust. You can decide which sounds best for your car.
 


Plainrt

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#13
I have mountune and love it. I do use a longer hanger in rear to get tips down lower. This is common problem with many aftermarket exhaust though.
 


kivnul

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#14
Back to the original post, from how I understand it, turbo'd motors do not require any backpressure after the turbo therefore there is never a problem with going to a freer flowing exhaust setup after the turbo. For the FiST, the stock exhaust (including the cat) is not overly restrictive with the stock turbo (even when tuned) so there is next to no benefit from upsizing the exhaust. Once you go Hybrid or bigger the stock cat and tailpipe become a hindrance to performance and could use upsizing.

As to Mountune V Thermal R&D: both are excellent exhausts. I have the Thermal (paired with a Mountune Cat) and quite enjoy the sound of it. I have had a banded joint in it come loose during a Autocross. After refitting and torquing it down I have had no further mishaps over the last 2 years.
 


Last edited:

Dpro

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#15
The Thermal does give more sound (good sound, mind you). It’s not quiet. I drove behind a car with one. I’ve heard good reviews for the FSwerks exhaust too as another option. There are plenty of YouTube exhaust sound clips for these exhaust. You can decide which sounds best for your car.
hmm I wonder who that could have been? :ROFLMAO:
 


Ford ST

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#16
The Thermal does give more sound (good sound, mind you). It’s not quiet. I drove behind a car with one. I’ve heard good reviews for the FSwerks exhaust too as another option. There are plenty of YouTube exhaust sound clips for these exhaust. You can decide which sounds best for your car.
I have a fswerks it's a good exhaust. Watch for Black Friday / cyber monday deals.
I have one of their systems on another car as well it's probably 8 years old now.

Sent from my LG-LS997 using Tapatalk
 


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Location
Weed, CA, USA
#18
I have ridden in cars with both systems.

The Thermal is louder under loaded acceleration. The Mountune is quieter under load- and generally a little quieter.

As others have said a larger exhaust does not provide much (if any) performance gain. I chose the Thermal because I find it easier to drive the car well if I can hear it.

The Thermal is deep at idle, reminds me a lot of the way a newer BMW M series sounds. It is noticeable but not loud. A quick rap of the throttle sounds good in my opinion but isn’t loud. However, under load the Thermal can get a little rowdy (loud). It is true that the Thermal has zero drone.

If I cruise around and keep it quiet I am driving like a responsible adult. If I load it up enough where it get a little rowdy I am driving like a bit of a tool. Think of it like a fuel mileage training method.

Cruising at 70 mph in 6th gear is almost indistinguishable from the stock exhaust. Quiet and comfortable inside. To me the magic number where it gets louder inside is about 3,000 RPM. Going 80 in 6th you can tell there is an exhaust on the car.

Both are good choices- for me the Mountune was too similar to stock.
 


OP
DaveZtoA
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Location
Edgewater, NJ, USA
Thread Starter #19
I have ridden in cars with both systems.

The Thermal is louder under loaded acceleration. The Mountune is quieter under load- and generally a little quieter.

As others have said a larger exhaust does not provide much (if any) performance gain. I chose the Thermal because I find it easier to drive the car well if I can hear it.

The Thermal is deep at idle, reminds me a lot of the way a newer BMW M series sounds. It is noticeable but not loud. A quick rap of the throttle sounds good in my opinion but isn’t loud. However, under load the Thermal can get a little rowdy (loud). It is true that the Thermal has zero drone.

If I cruise around and keep it quiet I am driving like a responsible adult. If I load it up enough where it get a little rowdy I am driving like a bit of a tool. Think of it like a fuel mileage training method.

Cruising at 70 mph in 6th gear is almost indistinguishable from the stock exhaust. Quiet and comfortable inside. To me the magic number where it gets louder inside is about 3,000 RPM. Going 80 in 6th you can tell there is an exhaust on the car.

Both are good choices- for me the Mountune was too similar to stock.
Makes sense and thank you for the detailed explanation, very helpful and useful.
 


OP
DaveZtoA
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Thread Starter #20
For anyone that has the Mountune exhaust or experience with it. Have you experienced any drone during highway cruising or any driving conditions? I love the fact that the Thermal doesn’t have any drone at all under any driving conditions. But thinking it might be to loud for what I am looking for. The Mountune seems to have a more tame and less loud sound then Thermal. But I am trying to confirm if the Mountune exhaust has any drone at all? Also with the new batch of mountune exhausts coming in. Do we know if they are still going to have the same install issues and be as difficult of an install? Thermal seems plug and play and not the case with Mountune, from what I understand. Are the Mountune tail pipes to close to the bumper and causing melting or the potential to? The description says it comes with, Robust OE Type mounting bracket and hangers. Has this solved some of the issues and is there a need to buy the mountune upgraded heavy duty exhaust hanger kit? Any other NVH worth mentioning with either exhaust?
As always, appreciate everyone’s help, insight and feedback.
 


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