Strut brace question

D

David-H

Senior member
 Prees, Shropshire
Need some help / advice.

I've changed the front and rear suspension on my MC and fitted the Bilstein B12 kit (Eibach springs + Bilstein shocks, 20mm lower than standard at the front and 10mm lower at the back) which seems to have improved the handling somewhat.

Next I'm about to change the 18" OEM 224 wheels and tyres to 19" 313Ms with 235/35/19 & 265/30/19 Eagle F1 AS2 tyres with 5mm Eibach spacers on the front and 10mm on the back.

Question is what else to improve ride / handling (road only - no track).

What are the merits of the OEM strut brace (~ £229) or even the AC Schnitzer racing strut brace which looks great but is quite pricey (~£625).

Are there any downsides to fitting a strut brace? :?
 
DLH said:
Need some help / advice.

I've changed the front and rear suspension on my MC and fitted the Bilstein B12 kit (Eibach springs + Bilstein shocks, 20mm lower than standard at the front and 10mm lower at the back) which seems to have improved the handling somewhat.

Next I'm about to change the 18" OEM 224 wheels and tyres to 19" 313Ms with 235/35/19 & 265/30/19 Eagle F1 AS2 tyres with 5mm Eibach spacers on the front and 10mm on the back.

Question is what else to improve ride / handling (road only - no track).

What are the merits of the OEM strut brace (~ £229) or even the AC Schnitzer racing strut brace which looks great but is quite pricey (~£625).

Are there any downsides to fitting a strut brace? :?
Click to expand...

I can't think of any real downsides, apart from the cost I suppose, though I don't know how much difference you will feel on the road. The primary purpose of a strut brace is chassis stiffness - as it ties the two suspension towers together and prevents independent movement.

To be honest I suspect your ride quality will go down when you fit the 19s.
 
DLH said:
Any views on the strut brace(s)?
Click to expand...
They do tighten up the front end and give a noticeable improvement to the steering feel because they prevent slight movement of the tops of the suspension towers from moving relative to each other, which must happen, especially on bad roads. I have the Strongstrut strutbrace on my ZMs.
 
Do you have the full Strongstut kit with front & firewall braces of just the front brace?
 
I have the full StrongStrut kit. I would say that on my car at least the front brace very slightly fouls the little rubber pipe thing (I assume it is a breather or something) on top of the engine.
 
exdos said:
I just have the front strutbrace because the two OEM firewall braces already do that job. :thumbsup:
Click to expand...
Stongstrut themselves seem to think that the OEM firewall braces aren't very good?
  • The factory installed strut to firewall braces are poorly designed. The ends are flattened out to a thickness of 1/8 of an inch which provides almost no additional support or rigidity. It's the same old engineering fact but true, a chain is only as strong as it's weakest link and1/8 of an inch is weak indeed! We understand from many of our customers the ends of the OEM braces are cracking from metal fatigue and the dealers are welding them back together. Our replacement firewall strut braces greatly improve the performance and appearance over the factory version. The strong-Strut components are available separately, firewall braces only, or as a complete set.
 
tertius said:
I have the full StrongStrut kit. I would say that on my car at least the front brace very slightly fouls the little rubber pipe thing (I assume it is a breather or something) on top of the engine.
Click to expand...

Your comment has just made me go and check. I can pass a piece of 3/16" piece of plywood between the breather pipe and the underside of the strut brace. I have the Vibra Technics engine mounts if that makes any difference, but the strut brace didn't touch with OEM engine mounts either.

DLH said:
Stongstrut themselves seem to think that the OEM firewall braces aren't very good?
Click to expand...
They would say that when they want to sell their products, but they do have a point. My take on this is that OEM braces will probably only fail when there isn't the additional strut brace which completes the triangulation between the suspension towers. I preferred to spend the cost of buying the two firewall braces on a Turner Motor Sport Rear trailing Arm Bush Limiter Kit , see: http://www.z4-forum.com/forum/viewtopic.php?f=9&t=38918&p=569454&hilit=Limiter+kit+exdos#p569454
 
exdos said:
tertius said:
I have the full StrongStrut kit. I would say that on my car at least the front brace very slightly fouls the little rubber pipe thing (I assume it is a breather or something) on top of the engine.
Click to expand...

Your comment has just made me go and check. I can pass a piece of 3/16" piece of plywood between the breather pipe and the underside of the strut brace. I have the Vibra Technics engine mounts if that makes any difference, but the strut brace didn't touch with OEM engine mounts either.
Click to expand...

I have the Vibra-tech mounts as well now - might have another look. However, for clarity, it doesn't touch when at rest - it obviously happens when driving - you can see the wear on the strut brace.
 
I'd say the OEM strut brace is 60-70% cosmetic and 30-40% of mechanical use. For road use only the ratio is further towards being solely cosmetic. What are you hoping to achieve by fitting it? RTAB limiters will markedly improve the feedback from the rear under load, especially when cornering under power. Uprated ARBs (eg H&R) will reduce body roll and certainly improve handling and feedback when cornering. It depends what you're aiming for...
 
BMWZ4MC said:
I'd say the OEM strut brace is 60-70% cosmetic and 30-40% of mechanical use. For road use only the ratio is further towards being solely cosmetic. What are you hoping to achieve by fitting it? RTAB limiters will markedly improve the feedback from the rear under load, especially when cornering under power. Uprated ARBs (eg H&R) will reduce body roll and certainly improve handling and feedback when cornering. It depends what you're aiming for...
Click to expand...
Just aiming for a more stable, predictable ride for fast road use and better than the standard OEM setup.
 
BMWZ4MC said:
The RTAB limiters will make a greater difference than the strut brace.
Click to expand...
OK - thanks for your advice. I've ordered the RTAB limiters and sent an enquiry to StrongStrut for their full kit.
 
gwatson said:
Definitely on my list. Which kit did you buy and from where if you don't mind me asking.
Click to expand...
The Turner Motorsport bush limiting kit from Turner Motorsport in the USA but be aware that postage is high!
 
You must log in or register to reply here.
Back
Top Bottom