Front Strut Brace for 1988 M6 - Racing Dynamics Interference

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Sbeaud
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Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by Sbeaud »

As part of my suspension refresh I purchased a Racing Dynamics front strut brace (https://www.racdyn-usa.com/PROD/196+99+24+010.html). It's noted as fitting the US M6. After installation I ran into an interference issue with the throttle. Wondering if anyone else has used this brace on a M6 and if there are fitment issues? Any suggestions would be welcome!

Thanks

Scott
1988 BMW M6 Racing Dynamics Strut Bar Interference.jpg
1988 BMW M6 Racing Dynamics Strut Bar Interference.jpg (386.98 KiB) Viewed 412 times
1988 M6
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by bpoliakoff »

It should have been made higher to avoid the throttle pate or to fit behind It. I am using a Hartge strut brace that I found, and it fits perfectly
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Slownrusty
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by Slownrusty »

That sucks!

Have you contacted RD and given them this feedback?

Yasin
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by bpoliakoff »

In their ad, shown here, the bar is fitted on an "M". If you look at the picture, at least to me, the throttle doesn't appear to be the same there for its has the clearance I think that is the problem
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by kronus »

It doesn't look completely installed in their photos, I wonder if they just set it on the M6 and figured "eh, good enough"
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by hornhospital »

You are absolutely correct. They have ONE nut on the near-side mount and NONE on the far side. I call false advertising. The studs aren't even through the mounting holes on the far side mount!
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Sbeaud
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by Sbeaud »

Thanks all. Yes, I noticed as well that their own images did not show the strut installed! :-k Wonder why? But the application list on the site notes the M6. I've contacted them by email with the following response:

Mr. Biaudry,

Thank you for your order for Racing Dynamics performance accessories for your BMW. I am sorry that this interference is occuring. I know the owner of a local BMW service facility
who installed this brace on his personal M6 without this clearance concern. But I also know that an 1988 M5 owner did have a similar clearance concern. I wondered if the placement
of the motor in relation to the shock towers was different in the M5 E28 chassis vs the M6 E24 chassis like yours. Or aged motor mounts shift the motors in relation to the shock towers.
My first thought is loosening up all the nuts and bolts associated with installing this brace, pushing everything towards the front of the car (there is slop in all the connection points/holes of the strut brace), then tightening down everything while holding it forward. I hope this makes sense. After doing this, if you still have interference, you may need to grind down the side of the throttle cable bracket a bit.

Regards,

Scott
The Racing Dynamics Sales Team
www.RacingDynamics.net


My response:

Thanks for the reply. There really isn't any additional clearance in the mounts to shift the bar forward. And it's not possible to grind the throttle lever down since that area is clearly important to the strength of the lever. I'm afraid if I can't resolve the issue I'll need to return the bar. What is the process to do that?

Thanks

Scott Beaudry


I have not heard back, so it's time to give them a call.

Scott
1988 M6
GAflyer
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by GAflyer »

Scott,

When I bought my M6 in 2007, a Racing Dynamics strut brace had been previously installed. I do not know if RD has made any modifications to their brace since 2007 (hole spacing, etc.) I have never had any issues attaching it to the tops of the strut towers (the 3 nuts each side).

Upon comparing your first picture to a similar picture of my installation, it appears likely that whoever installed mine bent the throttle bracket slightly in the direction of the firewall to make it all fit. I have never had any issues with interference with throttle movement (based on this apparently non-standard geometry).
M6 strut brace.jpg
M6 strut brace.jpg (191.13 KiB) Viewed 271 times
Whether you choose to keep the RD brace or send it back, at least I wanted you to know it is possible to attach it (at least it was on my M6). As to how much it affects the car handling, I couldn't say. I don't drive my older cars very aggressively, and I haven't driven the M6 without the brace.

Rob
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Sbeaud
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by Sbeaud »

Rob, thanks very much for posting. It's really worthwhile to have a apples to apples comparison. Even after reviewing the pictures it's hard to determine what's driving the difference. :-k
  • There does not seem to be much difference in the engine-to-body relationship - engine fore/aft location.
    The strut bar mounts look similar.
    Throttle bracket to motor is the same.
A couple of additional pictures of my application. Given how much interference I have I don't think bending the bracket would get me enough clearance. In addition to relieving the crash condition I would need ~5mm plus for engine roll, fore/aft movement.

I called Racing Dynamics and they said they will send a return authorization. A little frustrating - I liked the strut brace and I was looking forward to an improvement in rigidity. It also costs me a few bucks since the nuts are one-time use!

Looking now at the Bavarian Autosport (https://www.ecstuning.com/b-bavarian-au ... 10408~bav/) and Racingline (https://www.ecstuning.com/b-wiechers-sp ... 67013~wie/) strut bars.

I'll measure the Racing Dynamics and see if I can compare the bar width to these. Any other suggestions by the group are welcome!

Thanks again Rob.

Scott
1988 BMW M6 Racing Dynamics Strut Bar Interference - 2.jpg
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1988 BMW M6 Racing Dynamics Strut Bar Interference - 3.jpg
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1988 M6
K1W1
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by K1W1 »

The strut I bought also needed a tweak. Tho not as much as the (poor quality sorry) photo attached makes it look.

Came from the "B2D shop" in the UK (Description; steel drift race motorsport front strut brace bar E28 E24 M6)
GBP 100 delivered to home in NZ was a bargain.
Strut brace.jpg
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Sbeaud
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Re: Front Strut Brace for 1988 M6 - Racing Dynamics Interference

Post by Sbeaud »

Very interesting - thanks very much for the picture. That seems like a good work around. I'd like to exhaust some other alternatives before taking that step. I don't have a welder, though I have a friend that might be able to help. Seems like the bar itself would have to be lengthened slightly to make it work.

I'm still waiting for the return authorization from Racing Dynamics. I'll have to give them another call to remind them. Still open to other suggestions as to a brand of strut that might offer more clearance.

I've gotten sidetracked a little - my heater blower fans are doing the infamous "always on high" failure. Some great write ups from a few years ago are really useful. Transistor is ordered and I'm taking the controls apart now.

Thanks

Scott
1988 M6
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