Hi All -

I don't even have my R56 ordered yet (probably this month + need to get my R53 ready FS), but trying to line up mods to do immediately. Having trashed a pair of front control arm bushings in my R53 & realizing how long ago I *should* have replaced them, the PSRS for the new car interests me a lot. However, i've heard a rumor that the set screws loosen up too easily & cause rattles, etc. I wonder if any of you have any experience with that?

 

Nope. But I'm curious as well.

Also looking at these (http://www.mini-madness.com/index.as...ROD&ProdID=244):



If the 1st gen and 2nd gen arms are the same... if these will then fit the R56. I like the fact that the Alta pices have some degree of adjustment to them, though... provide some balance between caster adjustment and anti-lift characteristics. I would assume these also need to get pressed in, too.

 

I have not had any of the set screws loosen up from the ones i have installed, but i have heard about that issue. but never actually talked to someone that it has happened too. when i install them i make sure i use loctite and Tq. them to the 80 inch lbs.

 

Has anyone posted alignment numbers pre and post Alta PSRS install? I realize it has multiple settings, but what sort of changes does it make?

The Bavarian Autosport offset bushings I had installed change the caster from around 4.5° to around 5.5° on my Cooper.

 

i do a lot of alignments and the numbers are all in the 3.5 to 4.5 deg range. when adding the PSRS units, you get about 1 more.

 

R53 and R56 front control arms are not the same; you can see this on RealOEM.com too. The orientation of the outer ball joint is different. The Madness arms are excellent; though an even better setup would be optional offset spherical bearings! What Madness needs to do for the R56 is adapt these tubular chro-mo arms and do offset rear bearings!

 

Ahhhh, OK. So it's the bracket that the bushings are pressed INTO thats the same! I think I'm getting the picture (slowly).

 

Correct. Inner bushings are the same, outer ball joints [and subsequently the arm] are different.

 

Big update:

I've driven many R56's over the past few months. A Cooper with open-diff, Cooper S with open-diff, Cooper S with LSD, and finally, a Cooper S with ALTA PSRS and LSD. Prior to this series of drives I was convinced the factory clutch-pack LSD was to blame for the grabby and numb steering feel in the R56. After these drives however, it was revealed the LSD isn't the source of the steering feel weirdness, and it is in-fact the front control arm bushings. paulsminis was nice enough to let me test-drive his Kermee at The Dragon. Paul's R56 MCS had the ALTA PSRS's and factory LSD. In short, the steering feel is superb and 95% as good as the steering precision and accuracy of my all-spherical-bearing R53, no joke.

What does this mean? It means the factory front control arm bushings are in desperate need of reinforcement or replacing. Their deflection, even with Cooper torque levels, are significant enough to induce suspension misalignment and generate this sort-of torque steer effect. Driving Pauls R56 convinced me firmly the R56 is fairly easily transformed into a world-class drivers' car just like the R53.

Cheers,
Ryan

 

Agree with your points. My '08 MCS is dropped on H&R Street Perf coilovers and rolling on 18" lightweight wheels with Michelin PS2's and still does not take well to sudden acceleration and bumpy high load corners. Very darty with the front-end hunt. I attribute some of the handling woes to the new wheels (offset difference vs OE et causing a change in scrub radius). I think front-end bushings are also contributors to inconsistent handling. I still love the Mini and think it has potential...if I can crack the code on fixing the handling. My previous MKIV R32, out-of-the box, was and is still my weapon of choice for bombing down unfamiliar roads.

 

From the website..
"The ALTA PSRS uses a firm bearing material"

Exactly what is this material... a bearing surface or a firm material like Derlin.?

 

When I saw them at MOTD and had them in my hands it looked like they're just a steel spherical bearing in an aluminum carrier. Steel is pretty firm, LOL!

 

it's actually some type of plastic but they are very hard. but they are in an alum carrier.

 

How about the mini madness poly bushings? They make a pretty good point that steel/aluminum bushings will transfer a lot of vibration compared to the poly ones they make.

Anyone driven both to make the comparison?

 

from all the PSRS units i have installed. i never feel them after they are installed.

 

i would like to hear more about the mini madness bushings . do they give the sharp steering feel back like the alta psrs? i do like the price of the madness bushings. i have the engine mount bushing and i like it .

 

Thanks Chad for the clarification. It sounds like perhaps ALTA is using a Delrin or Teflon lining.

Regarding polyurethane bushings; they will definitely improve the precision of the suspension articulation versus the very sloppy "spoked rubber" stock pieces. They will offer some minor compliance; they also are centered so they don't add any more caster or anti-dive. These pieces will not change the geometry, just keep the stock geometry within a much tighter spec. I would put them high on the shopping list, personally.

 

considering all the labor involved in getting that rear control arm mount in & out, plus pressing the bushings, would it really make sense to cheap out on the poly bushing instead of putting in something that adds some steering improvement ?

I think those rear bushings are about as big a job as anything, I'd hate to have to do it twice.

 

Just to clarify n1tr0, we're talking about the front control arm bushings. They are somewhat confusingly in the rear of that control arm, as the control arm is a dual-mounting-point "L" shape.

That said, replacing the front control arm bushings is a HUGE job in terms of labor. You either need the factory MINI tool to press out the old ones and press in the new ones [by removing and probably destroying the ball joints], or remove the entire front subframe and then being able to remove the control arm bushing carriers, which includes the front sway-bar. This is not a light job, and even an experienced MINI-tech demands several hours of tough labor.

I would not say using poly bushings is being "cheap". It all comes down to how hard-core you want your MINI. In my experience, I find solid spherical bearings for the front control arm bushings totally acceptable, however my threshold of tolerable NVH is much higher than most here, and astronomically higher than those that get bothered by a little interior trim wiggle or squeak. That said, a solid spherical bearing will wear out much sooner on a daily-driven/winter car because they have no protection. As such, a solid polyurethane bushing would be a much more reasonable solution in keeping NVH near stock-levels while eliminating the horrible slop the stock spoked-soft-rubber bushings have. Poly bushings will last a long time, much longer than the factory rubber pieces, so there shouldn't be any concern about doing it twice. Did you have a bad experience with poly bushings in the past?

 

Not to get flamed but my experienced has been negative for poly, and IMHO are not worth the hassle. First they need grease nipples/fittings to be fitted to make sure they are lubbed up all the time or they dry out. They deform from load and need replacing over time i had to replace them in some control arm in season, where OEM last 5 years or more. They limit movement strictly in one direction when in some cases there is some multi axial movement in the design so you can bind on the bushing or suspension movement. The work very badly in cold climates.

I have had excellent experience using sku 8644K11 (hardness 80A) or 8644K18 (hardness 94A) from McMaster-Carr. To make OEM bushings stiffer and have the same range of motion, but you will have to press the OEM bushings to get a proper curing and shapping. I recomend this to ploy replacements. The trailing arms bushings were not available for DC/EH civic chassis so this was one of the only options. Again, everyone has their differing experience.

In the end i replaced all my Poly bushings in my track car with spherical and it did wonders and had not issues listed above. Over all spherical is totally the way to go. Or stick to OEM.

 

I know which part you're refering to .. rear of the front control arm, just trying not to be too wordy...

I have seen poly bushing kits wear out far faster then regular rubber, sometimes within the first year of use, just like anything, it's all about the quality of the product.
eg. taken from one of the bmw forums
Polyurethane comes in a seemingly countless number chemical variations with vastly differing properties. I've cast all sorts of parts like engine mounts using different hardnesses/mixes with varying results.
All I'm getting at is that I don't mind experimenting w/ some inexpensive poly bushings if they're easy to get at & replace if they fail/wear out, but the rear bushings on the front control arms are in the most miserable of places to get at, so I'll probably go w/ the tried & true Alta's (or wait it out for some Mini Madness R56 control arms).

 

I have a set of Madness front control arms on my R53 and they are very high on the list of "best mods for R53", right behind the supercharger pulley. I can't wait until Madness comes out with versions for the R56. The solid spherical non-offset bearing is superb.

 

as soon as issue 2 of the NAM Alliance is released, you can see a full how-to with lots of great info (& photos) on how to install a set of PSRS, and it is on a R56. to replace it on a R50/52/53 is about the same. we also offer the PSRS preinstalled into a control arm bracket so you would not need to press anything. you would get the unit pressed in ready to bolt up and put the arm on. then you just send your old brackets back. we even paint them a nice black or red to make them flashy. give us a call to talk more about this and look for the R56 PSRS install here on NAM.

 

how hard is swapping the bracket on the R53? I'd like to do this at some point

 

you need to drop the sub frame. i would not do it any other way. it may seem like a lot of work, but it's faster to drop it because you can get to every bolt with ease. you can spend hours fitting to get to one or two bolts because the sub frame is to close to the body. a few extra bolts and to drops right down and everything is in the clear and easy to get to and re torque.