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RMM Comparison

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Orange County
#1
Hey there,

So I'm about ready to grab a RMM for my 18, but I'm running into a lot of conflicting opinions on the characteristics of the available options. I'm trying to get an idea of which one is the most ideal for my application: daily driver with plans for future autocross events. I drive like a twat sometimes, but also commute to work.

I picked up the Mountune as part of the discounted kit they sell with the AP3, but since then I've heard a lot of negative feedback, specifically about them being loud and potentially coming apart under hard acceleration. Of course, I understand that the vast majority of opinions online are going to be from people who have something to complain about and people who are happy with it have less to say, so there's some negative selection bias.

Anyway, my goal is to get a collection of opinions so that I can have a better idea of how best to spend my money. These are my collected observations, feel free to correct them!

Cobb: Softer, less NVH, possibly too soft
Mountune: Stiffer than Cobb but on the softer side, potential problems with squeaking over time.
Torque Solutions: Cheaply made, poor product
Whoosh: Better made version of the TS design, new product
Boomba: Very stiff, potentially too stiff for daily driver
cp-e: Less stiff than Boomba, more than Mountune.

My knowledge is fairly minimal and based on nothing but internet research. I'm hoping that some people who might have some more advanced knowledge could point me in the right direction!
 


TyphoonFiST

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#2
You have most likely seen my posts....I own a Boomba RMM ....Been In the car now for 50K. DEFINITELY has held its own. I Run a Gen2 GTX2860R. The Vibes are not as bad as most people make them out to be. LOVE IT! If I was going to get another RMM it would be a CP-E...period. Look at the design. What's not to love? All RMM need some time to break in.....Remember that.Good luck!
 


FiSTerMr

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#4
Anything with poly will eventually make noise and need lubrication. Poly tends to "oval out". I have heard of the issues with the mountune, and I suspect that the Cobb will eventually do the same thing. I was gonna get the CP-E, as it's made with EPDM and not poly; but came across a good deal in the FS section on the Cobb that I couldn't pass up.

I have the Cobb, as noted, and no noises/issues as of yet, but I haven't put too many miles on it, maybe around 5k.

TBH, I don't feel much of a difference over stock, except for the added vibrations at certain rpm (which don't bother me). I think a large part of it is, that I'm not modded whatsoever, so it's probably wasted on me. Maybe if I was putting out more power, I would see a benefit. Also, on the 2016/7+, Ford beefed up the OEM one that gets put on the ST versions of the Fiesta, so getting an upgraded aftermarket RMM has less of an impact.

Although, for me to make the best evaluation of its benefits/drawbacks, I would need to go back to stock.
Going from stock to a mod, will give you an initial impression. But it's not till you do a swap back to stock, that you can really assess the benefits/drawbacks.

Hope that helps [emoji106]

2017 Magnetic FiST w/Recaros
 


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#5
I had the boomba for 80k miles plus. I have the CPE now. No nvh and it works so good I can’t tell it’s even there. My idle is at 950 rpm because of the cams so I can’t say if there are vibes at stock idle with the a/c on. If you do have this condition have your tuner raise the idle rpm
 


kivnul

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#6
I've ran a Mountune RMM for about 40k, 15k with a 47R turbo. I have had zero problems with it and like it.
 


flbchbm

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#7
I have the 70a durometer AWR for a month now. Tons of AC-on idling vibration. I have a slo-mo video I need to add here, but I'm at work (no phones) and then forget when home. It looks like the steering wheel and base are flexing. It's funny looking. I'm getting used to the vibe and noise that comes with it. I would like it to be less, but the 70a is their softest. For shifting, it feels good to me and does not have me wanting more. Yet. YMMV...
 


Se7eN

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#8
I've had a number of them some a few days and some lot more.

Stock - filed with liquid poly, feels stronger than a Cobb mount.
Mountune - Stiffer but creeks if you don't lube it up right
Boomba - Way to harsh, was impossible to read the dash properly with the A/C on, only had it a week. Have driven the car that has it now, it's gotten a tad better but still wouldn't have it for daily driving.
Torque Solutions - Failed a total of 2 times. Once at the track the big bushing broke apart in a hard launch (on stock turbo). Second time the small bushing gave way and allowed for a large amount of wheel hop.
Whoosh Race Spec - Currently running this one, only has about 150miles as I'm breaking in the new clutch and installed it. Feels great the NVH more then all the other softer RMM except for the Boomba. Still at Idle you barely feel it vibrate.

Additional Data: Had the 2 Inserts for the top mounts installed about 6 months ago while still using the TQ solutions.
 


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