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alternatives to the butt strut and ground clearance

Discussion in 'Z3 Roadster & Coupé' started by joey, Nov 17, 2013.

  1. joey

    joey Zorg Addict
    British Zeds The M44 Massive

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    having read some testimonials on the butt strut, the marked effect of tightening things up planting the rear wheels better and counteracting the understeer characteristics of the Z3 I have decided to go ahead and fit one..

    however before I do I have some questions..

    is there cheaper UK alternative,? as it seems expensive for what it is..

    secondly my car is not lowered and I have no plans to do so but have a fair amount of speed humps where I live and I go into london regularly (speed hump capital of the world!) so am wondering if anyone has had issues with one or has any advice or opinions on it..


    thanks all


    joe
     
  2. Woody100

    Woody100 Zorg Addict

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    I have one fitted on my car and the car is lowered 30mm than standard and I have to be very careful !! Even down country lanes if you put your foot down it can ground out ! Speed bumps are ok when you know they are there cause you can act accordingly but when you get caught out and it's too late to take action beware !!
     
  3. Stormy_be

    Stormy_be Zorg Guru (I)
    Belgian Zeds

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    I migth have a "cheaperalternative" by March.........
     
  4. Boysie

    Boysie Zorg Guru (I)
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    They are definitely not for a lowered car, that's how I got mine
    I think Strong Strut sort mention they are not suitable for lowered cars
    Shame its a great add on to the car
    I'll you know what difference the body brace feels like when its fitted :happy:
     
  5. joey

    joey Zorg Addict
    British Zeds The M44 Massive

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    ok,so to confirm, fine if the car is not lowered in anyway..seems to be the consensus that a standard car will be fine.


    koen , sounds interesting! I am already taking those ARB's from you and am going for poly bushings on them so what else do you have?

    I will also change the rear coil springs for new as the car is sitting marginally lower on the rear driver side..have had it checked an there are no problems,and its so slight it's taken me 6 mths to notice it!.

    if anyone can recommend something I can fit other than OEM that will do a better job feel free to chime in.


    boysie I would be really interested to hear your thoughts on the butt strut when it goes on...


    thanks

    joe
     
  6. Stormy_be

    Stormy_be Zorg Guru (I)
    Belgian Zeds

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    Joe,

    About your springs: it's not per default because the ride is a little lower on one side that this has to do with the springs.
    If a bushing has 1mm of play...with the leverage it can already create some difference.
    Or it could be the rubbers on which the springs sit, etc, etc

    I'm not saying it can't be the springs, but it's not per default.

    Regards,
    Koen
    PS: by march I already have enough on the list. But I'm sure other things will follow...........
     
  7. deano1712

    deano1712 Zorg Addict

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    Just fit solid subframe bushes instead or fill the voids in the standard bush with inserts or expoxy resin. The flexibility of the standard bush at the front of the subframe
    is what causes instability and rear wheel steer. Thats what you need to fix. The butt strut doesnt do anything at all except make sparks and add weight - a complete placebo mod.


    Sent from my C6603 using Tapatalk
     
  8. joey

    joey Zorg Addict
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    Hi deano,

    i'm taking koens anti roll bars from his 2.8 and will fit poly bushes front and back, as well as some new coil springs, this should stiffen things up nicely along with the 17'' rims that will be going on too.. please excuse my ignorance but "subframe bushes" are they one and the same as the "suspension bushes'' everyone refers to when referencing body roll on the Z3?

    thanks


    joe
     
  9. swamper

    swamper Zorg Guru (V)
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    im about to find out as iv got one but not fitted yet...im going to give the M a good go on the twistys then fit it and run it again on the same day same roads and see if theres any difference.
    iv always looked at it that anything that can add stiffness in the right place can only help...the solid bushes (so iv heard) are to harsh...but the inserts are the way to go
     
  10. MAURICE THE MARTIAN

    MAURICE THE MARTIAN Zorg Guru (V)
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    Or you could just get a Z4.
    Lol.
    M

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  11. swamper

    swamper Zorg Guru (V)
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    old mans car...lol
     
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  12. MAURICE THE MARTIAN

    MAURICE THE MARTIAN Zorg Guru (V)
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    One you cant catch tho.

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  13. swamper

    swamper Zorg Guru (V)
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    haha...i dont wana... means iv got to talk to you if i do...!!!!
     
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  14. Boysie

    Boysie Zorg Guru (I)
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    I've contacted strong strut.
    And hoping to get reply via the forum regarding this remark, their input could be very helpful
    They sell thousands of these struts?

    I feel they make a difference,
    I think it's complete package though, engine, butt and body brace
    I didn't feel a lot of difference in the engine when first fitted, did the butt strut compliment and so on with body brace

    Wayne. When fitted try entering/exiting a roundabout fast, that was my first experience with butt fitted on the way to silverstone


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    #14 Boysie, Nov 20, 2013
    Last edited: Nov 20, 2013
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  15. Boysie

    Boysie Zorg Guru (I)
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    I received this from strong strut today
    shame he didn't post it on here

    Thank you for your inquiry, I read through the posts you referenced. Everyone is entitled to their own opinion of course but our customers can say it much better than we can. Please read some of the testimonials at this link http://www.strong-strut.com/rear_strong-strut_testimonials.htm
    The rear Strong-Strut is suitable for Z3’s that are lower slightly, not more than 13 mm. In any case, it does reduce ground clearance a tad but caution going over speed bumps is always good regardless. http://www.strong-strut.com/rear_strong-strut_testimonials.htm

    Best Regards,
    Paul & the Strong-Strut Team
     
  16. deano1712

    deano1712 Zorg Addict

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    It would be good to hear them explain how the butt strut works. What is flexing and how does the strut stop it?
    For front struts its obvious. There are assymetric loads going into the towers which are inherently flexible and tying them together (up to) doubles the stiffness and also prevents errors in steering geometry.
    At the rear there is no way the downward facing M14 studs are moving. In any case the rear beam is stiff and will apply equal loads into the bushes left to right. Tying the studs together with a flimsy bent bar wont help anything.
    Perhaps Im wrong though those testimonials are convincing (not).
    Am I coming across as grumpy? ;-)

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  17. Boysie

    Boysie Zorg Guru (I)
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    I got a engine strut, thinking it was a must have.
    Everybody else had one
    I assume that's how you become a good salesmen word of mouth.
    Like big loud exhausts, what do they really do?
    Deano you are more technically knowledgeable than most on here. And you are allowed an opinion

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    #17 Boysie, Nov 20, 2013
    Last edited: Nov 20, 2013
  18. badman gee

    badman gee Guest

    I've driven cars with and without struts.

    I did not notice any difference.

    Waste of money and time IMHO!
     
  19. Brian4

    Brian4 Zorg Guru (IV)
    British Zeds East Anglian Crew

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    Hi Joey regards 'please excuse my ignorance but "subframe bushes" are they one and the same as the "suspension bushes'' everyone refers to when referencing body roll on the Z3?'

    The subframe bushes are on the rear beam item 3 in the diagram below the suspension bushes are item 8
    Part no 2 is bolted into the car the bush is pressed into the beam 1 and is the fitted over the bolts and secured with item 4 which is also bolted to the side of the rear sill so in effect there is a strut brace fitted as the top of the bolts 2 are in the body and the bottom of them is braced against the sill. All the butt strut does is replicates the rear beam 1 with some 5mm plate.

    My opinion

    [​IMG]


    Most rear braces seem to be fitted to the top of the rear towers as per below.
    [​IMG]
     
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  20. swamper

    swamper Zorg Guru (V)
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    but in effect if the rear beam is running parallel with the strut fitted you are creating a box section?
    hence less flex (if any)

    but having had a look at mine..the ground clearance may be a problem
     
    #20 swamper, Nov 20, 2013
    Last edited: Nov 21, 2013

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