TAI (Torque Arm Insert) Bushing Mod... Here’s why.

The engine in a car vibrates quite a bit when it is running, especially 4 cylinder motors. It is mounted onto the frame of the car via engine mounts, which are constructed with a sound/shock absorbing surface (bushing) to do just that. Think of them a little shock absorbers between your engine and you, as you sit in the car on the seats, holding onto a steering wheel and grabbing a shift lever that are all mounted on that same frame.

The torque arm works on the same principle as those engine mounts. In our MINIs, as well as other transverse (sideways) mounted engines, it is designed to reduce the natural stress of the rotational tendency of the engine to roll on it's mountings while running (working to rotate the wheels...). And it has the same before-mentioned damping material (bushing) inserted in that arm to reduce the noise and vibration from being transferred into the frame and consequentially to you, also just like the engine mounts.

The MINI OEM insert (bushing) in the torque arm was designed (like a lot of other things in our newer generation MINIs) by the "Good Ole Beamer Boys" to transform a once cool little gutsy English sport car into an econo German car with a broader marketing potential to make them a lot of money (read: more). That is why "purists" (like myself), spend a lot of time and money replacing BMW’s redesign technology in an effort to return their new MINIs back to their original sports car roots and persona. And one of the ways to help accomplish this is to replace the OEM insert bushing with an after market one (I chose NMEngineering) that is made of a denser/stiffer material.

The procedure is actually a lot easier than you might think. Of course, like all work performed under a car, it is quite handy (and infinitely more safe and comfortable) if you have the car up on a lift. To do this modification you simply remove the attaching bolt from one side of the torque arm, temporarily rotate it downward, push out the old softie, and push in the new stiffy, and then reattach it in a reverse fashion. Voila! A quick, easy, inexpensive, simple, painless mod with noticeably beneficial results.

This modification accomplishes a major benefit to the feeling of the MINI in basically 2 similar ways. By increasing the density and lessening the softness of the bushing, there is less "give" for the engine (some theorize this can be as much as ¼”!) to take up when accelerating, giving you a much sharper response in the gas pedal (despite the fact it is connected to the engine with that gawdawful "drive-by-wire" module, and again, thank you Beamer Boys... technology? Eee-yah.). I also contributed to this new crispness by adding an accelerator pedal module re-map program (I chose Sprint Booster, which I recommend). And second, that same "gap" is reduced with the gear shift stability and throw feel because the transmission (and linkage) is connected directly to the engine and it's damping system also. Coupled with a short shift/reduced throw linkage pivot (I chose Helix, again, I recommend), you get a very distinct feel and a much improved accuracy when shifting.

Goodbye Bavarian econo car poodle lick, hello proper English sports car bulldawg bite. Chomp. Chomp... Chomp.

Some MINI people will not like the feel of this new, denser material after market insert, just like "purists" as myself do not like the dull, cushy, indistinct feel of the OEM insert bushing. There is a little more sound transmitted to the cabin, and a bit more vibration felt at idle primarily. But that sound and vibration is far from an annoying level, and after initially noting it, now I don't notice it at all. Certainly it is far less distinctive than the original pre-BMW classic MINI, and definitely less than your average MGB/Austin Healey/Lotus/Aston Martin/Jaguar of yesteryear, which are incidentally my favorite type of car. I also believe that the slight increase in vibration and cabin sound was reduced with time as the bushing was worn in and seated a bit. I personally have no regrets and think it was worth every penny. I would do it again in an instant, for certain.

The Cost? The NM Engineering product (which I recommend, but there are others), about $60, and labor (if you're not tool savy and handy, although it requires only basic skills), depending on their fee (it is a simple 5-10 minute job), $25 - $60.


Enjoy your MINI, that's what they're for, right?

 

This mod has been my favorite so far and is the best bang for the buck. It should come from the factory with a stiffer insert.

 

S&CLC - thanks for the explanation! Now I know why some have compared this mod to replacing the rear sway bar - after seeing my OEM, puny RSB, it was plain to see why my new one felt sooooo good.

Since I've gone with the D-1 Spec throttle controller, I can feel the engine rocking more than normal - especially if I forget to factor in the sensitivity of the new controller.

Just one question: once it's up on the lift (it sounds like I could tackle this myself) where is it exactly? And no difference between non-S and S models? Thanks again for posting!

 

Albie:

Check out this thread here on NAM, scroll down to the post 5-01-2011 from "jtbrown", good pics:

https://www.northamericanmotoring.co...-insert-2.html

Once you're under there you can't miss it though.

And yes, it's the same torque arm for all (Straight Cooper, Cooper S, JCW) the R55 and R56 models.

Also, remember, you are just replacing the brushing (insert) not the arm. I can't wait for your reaction when you do this mod...

Enjoy.

 

I would have to agree that this is a great bang for the buck mod. In a lot of ways, this should be the first mod. However, after driving around on the NM Eng inserts on my 2009 R56S manual transmission, I decided I wanted to go for the street version of the BSH R56 Lower Engine Mount. WOW! The car just launches unbelievably now. No torque steer or wheel hop like before, very responsive. Shifting was great with the NM inserts, but even better with the BSH part. Only problem is the 1500 mile break in period for the part. My rear view mirror for the first 20 miles was vibrating like mad along with the bad vibrations from 2500-3000 rpms. After the first 20 miles, it started calming down. And I have front and rear (behind the rear seats) strut braces and the TSW X-Brace installed. After seeing the stock torque arm up against the BSH, it is amazing the difference (forgot to take a photo of the two side by side). Now I am going to put the NM Inserts off my car on my wife's 2010 R56S (automatic).

 

I ended up with a bushing for an 08-up MCS will the arm off an 08 fit on a 2007 i didn't realized they were different when i ordered it off a member...

 

I just did the NM inserts today, and just to clarify, with the NM inserts, you don't actually take out the old bushing at all. You do undo the bolt, pivot down the fat end of the torque arm, and then press in two inserts, one from each side. These inserts fill the gaps in the rubber bushing which contribute to the spongy feeling. They do make the whole thing a bit stiffer, but at the core you have the same rubber as the OEM, which is why I think this design is so neat: it retains most of the core vibration isolation, but decreases the considerable spongyness. Then add a small metal retain bracket, place bolt back in, and don't forget to re-torque one or both bolts to spec (on my 2013 R56s the bolt specs are 108Nm).
In addition to the inserts in the fat end, it is also possible to swap the entire bushing on the smaller end, or even get an entire new torque arm with new PU bushings on both ends. These steps will further decrease slop, but will further increase vibration and noise transmission, and to a much greater extent that simply adding the inserts.
It does tighten things up considerably, and it does increase vibrations just a bit. To my feel, its mostly the buzzing feel that increases a bit. As pointed out by OP, some won't like this. I don't mind, and to me it's well worth the much less sloppy 'engine bouncing around in the bay' . I also added the BMS clutch stop, and am considering a short shifter next. I should also say that I never felt this was necessary in my old R53s, that car was tight, whereas the R56s feels like MINI softened it up quite a bit on the whole (in addition to adding that awful torque steer). Still, an awesome fun car to drive, and the bushing inserts etc.. just make it even better.

 

If it was an '07 Cabrio, I think you would. But an'07 hardtop should be fine.

Why are you swapping an OEM arm for an OEM arm? Something happen to yours?

 

No but hte bushing i ordered apparently only fits 08 and up MCS... this bushing is round the one my car is more diamond shaped...

 

Don't know if the the newer style arm will fit (I'd imagine that it would as long as the bolt hole diameters are the same) but I'd sell incorrect insert that you have and buy the correct insert.

 

touche

 

Sorry, but you're going to have to order the bushing for the 07, as they were triangular in shape. The 08's and up are round. They're definitely not interchangeable.

 

I ordered a new torque arm and the bushing from ECS for mine.

 

I was more interested though wether the arms were interchangeable and I could use the bushing I know have...

 

Per ECS the torque arms are interchangeable. Without putting my car on a lift I didn't know which insert to order either, so I just ordered a new (round end) mount and will install that and the bushing next week. With the miles on my car the original insert is probably toast anyway. ECS carries the Powerflex insert vs the NM part, so that is what I got. I'm gonna put 5-600 miles on it next weekend and will let you know what I think at that time.

 

What's the part number on the round end arm?

 

Torque arm http://www.ecstuning.com/ES41748/

Insert http://www.ecstuning.com/ES2650655/

 

Nice write-up!

I have an 07 but purchased a new engine mount that is the part number for 08+ and the matching NM insert, I shouldn't have a fitting problems.

 

If I remember correctly vehicle built before 8/07 had the trapizoid shaped insert (I dont know why they changed) and that is probably the hang up there. I'd just order the new arm from ECS and use the insert you bought already and call it good. That way you dont have to resell the insert. which can be a bigger headache then just buying the necessary parts.

 

Ok, so perhaps someone already told you that. Sorry for the repeat info. Should have read the full thread before posting. derr.

 

I have the 2012 Countryman S FWD auto tran, and whenever I floor the gas pedal the front wheel hops like mad, will this reduce the torque steer even on the automatic transmission? since the insert is to stabilize the engine, I am guessing it works just the same on the auto trannie.

Kevin

 

You wheel hop has little to do with the engine torque arm (aka vibration dampener), and everything to do with engine torque exceeding traction provided by your tires.

If you serious want to reduce wheel spin/hop, you should (in order of effectiveness):
1). Upgrade to stickier high performance tires (vs. all-season run-flop crap you got on the car now).
2). Upgrade the shocks (OE gas shocks, especially of non-sport variety, are way under-dampened).
3). Add limited slip diff (alas, not feasible with an auto tranny).

Torque arm just connects the bottom of the engine to the vehicle body via a little rubber bushing. The give in the bushing is minimal. The extra 1-2 degrees of roll you may be minimizing wont effect traction as the roll is in the direction of wheel rotation (not up/down or longitudinal).

If you still want the inserts, check the marketplace section. There are plenty listed for sale from the folks who don't care for the extra body vibration they transmit and deliver no performance gain.

a

 

There are other things that could be done to mitigate or solve the front wheel hopping.

- Don't get on the gas as hard when you don't have traction.
- Make sure the front wheels are pointing straight when you romp on the loud pedal.

There may also be mechanical problems that are contributing significantly to the hop, things like worn bushings or bad ball joints, bad shocks, or bent parts. A wheel alignment and a thorough check of the suspension bits might tell you about problems with those.

 

awesome write-up, now i totally understand the function. appreciate it

Kevin

 

It has always been like this since I got the vehicle, under hard throttle the front end lifts up too much so the tires cannot keep contact. I'm going to lower the car on H&R springs and see if that will reduce the problem a bit. it's currently sitting on OE spring/shocks (non sport suspension), and I'm guessing the OE shocks are bit too soft.

Kevin