Would anyone have sources for reinforced (urethane or else) rear upper strut bushings?

Please let me know what's available out there.

Thanks!

 

Peter of M7 has made some delrin bushings, of which I have a couple. I don't recall if he made any for the rear, but it couldn't hurt to ask..

 

Why not just eliminate it all together Alain? That's what I will be doing. We'll just make a whole new plate with a solid shock mount.

 

Here's your link, a Mini-Madness product. I have them on my MCS. Great improvement, makes the suspension work, and not the bushings. As the urethane doesn't compress as much as the OE rubber bushings, the car's rear ride height increases by about 1/2 inch. Not a problem with coilovers, but if you can't adjust your ride height, you may not like the results.

http://www.mini-madness.com/index.as...ROD&ProdID=260

MGC

 

I got some from Helix a couple of months ago - check with Eric.

 

Nice!

 

Mini-Madness:
http://www.mini-madness.com/index.as...ROD&ProdID=260

 

Greg, that was my original thought, but after speaking (through a friend who has contacts) with Moton, they mentioned the lateral loads of the MINI rear suspension design, based on Nuzzo's car. If you look at the angle of the upper plate, it makes sense to me.

My current suspension setup still utilizes some of the OE components. I have an upper spring perch under the OE cup and can tell you that there is quite a bit of movement there. Some of it is of course due to the bushing, but I am affraid that the shock shaft could take some of that lateral load if there's no give in the assembly.

I noticed the weakening of the bushing when it started rattling/banging under load. The upper cup is now touching my spring perch, judging by the marks left in the assembly.

This is obviously a race suspension.

May be the good Dr. can chime in.

 

Good points Alain. We have not yet put any thought into building these yet, but we will come up with something. Maybe a ball joint or something. I'll bring this up with my builders and see what we can start to design. I'd be happy to share with if you are interested.

 

Greg,

Whatever you come up with, I'm interested in.

 

Here is an approach to consider: Made a set of monoball rear strut upper mounts from cut down TC Kline rear shock monoballs for the BMW M3. The strut shaft size is 10mm, the same size as the BMW M3 shock shaft. The modified monoball assembly bolts directly into the stock rear strut mounting bracket.

Fine for the street. Not so fine for the track. Removed them in favor of the Madness urethane bushings. Why? Felt that the rear end was unstable under threshold braking at the track and on the freeway. The car would yaw and pitch. Put some compliance back into ther rear suspension and the instability disappeared. Not sure whether something else changed as well and whether the monoball rear strut mount was really the culprit.

Cannot attach photos, because of their size. Cannot edit the photos either. If anyone is interested in a photo(s), email me at: petrich@u.washington.edu and I can attach to a regular email. Don't bother to PM.

Regards,

John Petrich in Seattle

 

Good to hear from you John. It's been a while... I just referenced you in this thread last night!

https://www.northamericanmotoring.co...60715&posted=1

I'm going to check into getting some urethane ones. Thanks!

 

You sure about that? I just spoke with Eric and he says that he does not sell something like this, only the PowerFlex stuff (yellow & purple) and they don't make such a bushing for the top of the strut.

Madness has this market cornered I guess.

This was the 2nd time that I've spoken with Eric, and he was very pleasant to speak with, and helpful!

 

Ooops - my bad - Ordered some from Helix and some from Madness around the same time - you are right the Rear strut top bushings are from mini-madness.

I getting these put on next week

 

Well, if you don't mind, and can remember, kindly share your impressions... Thanks.

 

Tony B and the group,

Have

 

Tony B and the group,

Have been experimenting with the rear strut upper bushings. Have posted about my bad results with monoball bushings. Reverted to a set of new OEM bushings for the first half of the track season. Picked up a set of Madness upper strut bushings and have just completed two fast and furious track days on the Madness replacements.

The Madness rear strut upper bushings seem to work perfectly in my car. They definitely offer less compliance than the stock bushngs on inspection and with simple manipulation. The street ride is indistinguishable to me. On the track they performed perfectly. I don't know if I can tell that the car is more stable, but I think that the chassis sets up a little more quickly and predictably under braking/shifting for a turn. Under heavy braking, from 115 MPH on an admittedly rough track surface, the car settled quite nicely and there was none of that violent rear end hopping around that I experienced with the monoball bushings. (Don't think that I wasn't relieved.) The rear end rotates quite predictably and I don't perceive any little "wiggles" or minor motion that I would attribute to sloppy rear strut bushings.

I think that the rear strut bushings are a great component where one is working on tightening up the handling by minimizing unwanted bushing compliance.

Hope that this helps people,

John Petrich in Seattle

 

John, knowing you, and all that you've done, a kudos from you means something! Thank you.

 

Just finished an all day autocross school on Sunday. This past week I had the Madness delrin upper strut bushings installed, four helix rear control arms (vice h-sport), and the M7 USS. After realignment I was ready to go.

The car was amazingly predictable -- in the slaloms it felt even more planted and it would rotate on lift without being "snappy". I also noticed (like John) that on very hard braking the rear was more behaved will very little hopping.

One of the instructors (National level M5 driver) said it was one of the best handling MINIs he had ever driven. I got within .8 sec of his time.

David

 

David, thanks for remembering to share your impressions, and also those of the M5 driver/instructor. Good stuff!

It sounds as though you did quite a few things to impact the cars response, not just the uppoer rear strut bushings. I've heard so many wonderful things about the M7 USS, and I'm guessing that much of what you felt can be attributed to it (esp. the turn-in). I don't have one, so I can't say first-hand...

Hey, just to clarify, the Madness bushings are urethane, right? They don't look to be delrin...

I love to hear the opinions of others, but even more so from those who compete such as yourself. Best of luck to you the rest of the season!

 

David, Tony B and all,

Thanks for the up date on your experiences with the new bushings. Yes, the Maddness bushings are a type of urethane, not Delrin.

I am wondering how durable and rigid the M7 USS actually is? Are the USS installations holding up under use, or do they loosen up after a time? Never seen one in the flesh, just photos.

Regards,
John Petrich in Seattle

 

John, I too am/was thinking the same. First it was my overly **** concern about adding weight... but given the resounding input from others, that is no longer an issue for me. I truly believe that it makes for a very nice difference... simply based upon the volumes of folks who love it.

I asked Peter about its rigidity over time... To be honest, having become close with him over recent years, it was more difficult for me to ask than if he was just another vendor/tuner. I know the time he puts into his product offerings, and pride that he has for them... I've become an M7 fan. He told me that the way it was designed or tied together (triangulated if you will), it will perform as intended for years to come...

He still asks me on occassion if I want an USS... and I'm on the brink!

John, as you might know, there are several threads on the USS. You might want to go in there and ask folks who have had it for a few thousand miles if their impressions remain...

 

Just a couple ¢ worth.
I installed the OMP frame brace a couple months ago.
Here's the old thread

For $100 it does a really nice job as I commented in the thread.
Considering it's about 1/3rd the cost ( and maybe the weight Tony ) I feel it needs more opinions than just mine.

Thanks all for the info in this thread. I'm getting a bit more involved in auto-x this year and the suspension area is hwere I need the most improvement/help. Since I'm stuck in SM I don't have too much to worry about.
It's all about how many seconds back I'm in last place

 

I'm also running in SM now and you are right about measuring seconds back from first. Do you have or have you considered adding an HSport front swaybar? IMHO it helps get more grip.

Back on thread now - hijack completed

 

I've thought about it.
I've got this whole PSS9 vs FSD thing going on in my head right now.