Rear beam bush question.

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AdamGardner
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Post Sun Jan 31, 2010 10:39 pm

The rear beam/subframe bushes are knackered on my e30 road rally car, just wanted to know what bushes people are using for hard use?? Was thinking of going to poly bushes from power flex and changing the diff bush for a poly bush also. Any opinions welcomed on what to use.
telski789
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Post Sun Jan 31, 2010 10:41 pm

powerflex are the way to go fella!! all bushes should be poly,especially on a road/rally car!!
rix313
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Post Sun Jan 31, 2010 10:42 pm

If it's a competition car then I'd defo recommend upgrading to poly bushes. Powerflex do two versions, a fast road 'purple' bush or a full race hard 'black'.

One of my freinds recently fitted purple sub frame bushes to his iS track car and said there was a marked improvement with rear stability.

There is abit of a wait to be had for Powerflex stuff at the moment as their factory burnt down. They have got lead times down to a couple of weeks now from what I've read so they're on the mend :)
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Post Sun Jan 31, 2010 10:54 pm

Cheers lads ill get some ordered in the morning
RPM
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Post Mon Feb 01, 2010 9:59 am

Powerflex offer 2 compounds, purple and black the black being the harder of the two

I run purples on my race car, and am very pleased with my complete setup including bushes. I haven't driven on the blacks but I doubt there will be a noticable difference

Blacks are circa 15% more

We are a powerflex dealer, let me know if we can help out

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Post Mon Feb 01, 2010 10:35 pm

For a road rally car I would run new rubber bushes.. The beam is part of the rear suspension, rubber bushes will offer you more traction.. I run new BMW rear bushes with the voids filled with rubber on my car, and the rear end feels fantastic, very planted. That's with hard coilovers also, so more likely to show up any 'sloppiness'
Got cable ties? Get diffin..

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Bob_S
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Post Mon Feb 01, 2010 11:01 pm

Jhonno wrote:For a road rally car I would run new rubber bushes.. The beam is part of the rear suspension, rubber bushes will offer you more traction.. I run new BMW rear bushes with the voids filled with rubber on my car, and the rear end feels fantastic, very planted. That's with hard coilovers also, so more likely to show up any 'sloppiness'
I've always run BMW rubber bushes too and have to say that I found poly bushes poor and didn't suspend the axle as well as the rubber stuff.

RPM, I have no problem with your advice but blatent plugs all over the forum are bloody annoying it's kind of like alerting everyone you have a cure for genital warts.. nobody really wants to know unless they need it and in which case they will search for it.
Bollocks to this 24v scrap!
djs325
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Post Tue Feb 02, 2010 11:50 pm

I'd highly recommend PowerFlex too; have sorted some E30 people out with a couple of sets from BimmerWorld in the US; who just might still have some in stock if the UK factory is unable to supply right now.

Fitted race durometer rear subframe and diff bush to my mate's E30; he said it felt a lot nicer, but was easier to induce oversteer without making any other changes - basically he needed to learn to drive smoother, as there was less 'slack' in the rear axle assembly to compensate for his jerky pedal technique.

I used AKG in mine, wouldn't recommend again (not as easy to install as PowerFlex, room for movement still (around the bush not in the bush itself), but noticed a big difference in the 'pointy-ness' and responsiveness of my E30.
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stratos
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Post Wed Feb 03, 2010 8:36 pm

I made and fitted some solid ( ally ) bushes for mine ( a track only car ) raising the beam by about 20mm ( ie lowering the body ). It feels good , althoe Ive only had limited track time so far. Why would you want bushes in the subframe anyhow ?
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Post Wed Feb 03, 2010 10:47 pm

No intention to annoy or offend, will try and sit on my hands next time I feel the urge to post a link outside the the relevant selling forums.

PMSL @ the analogy though :lol:
RPM, I have no problem with your advice but blatent plugs all over the forum are bloody annoying it's kind of like alerting everyone you have a cure for genital warts.. nobody really wants to know unless they need it and in which case they will search for it.
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Jhonno
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Post Wed Feb 03, 2010 11:41 pm

stratos wrote:I made and fitted some solid ( ally ) bushes for mine ( a track only car ) raising the beam by about 20mm ( ie lowering the body ). It feels good , althoe Ive only had limited track time so far. Why would you want bushes in the subframe anyhow ?
For a smooth track only car, solid beam bushes are fine..

Rubber bushes reduce the vibration etc transferred into shell on a road car, but as the beam is also designed as a dynamic part of the system, they allow some movement which helps traction over rougher surfaces..

M3 Touring cars used harder rubber bushes to mount the beam iirc, though might be getting confused with Grp N
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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e30topless
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Post Wed Feb 03, 2010 11:47 pm

Bob_S wrote:
Jhonno wrote:For a road rally car I would run new rubber bushes.. The beam is part of the rear suspension, rubber bushes will offer you more traction.. I run new BMW rear bushes with the voids filled with rubber on my car, and the rear end feels fantastic, very planted. That's with hard coilovers also, so more likely to show up any 'sloppiness'
I've always run BMW rubber bushes too and have to say that I found poly bushes poor and didn't suspend the axle as well as the rubber stuff.

RPM, I have no problem with your advice but blatent plugs all over the forum are bloody annoying it's kind of like alerting everyone you have a cure for genital warts.. nobody really wants to know unless they need it and in which case they will search for it.
:rofl:
clarko74
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Post Sun Feb 07, 2010 5:08 pm

Jhonno wrote:I run new BMW rear bushes with the voids filled with rubber
How do you do that?
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MarkT
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Post Sun Feb 07, 2010 5:45 pm

I'm going to turn up some delrin sub frame mounting bushes for my track car. There are some alloy ones available, but not going to use them as I'm concerned about the alloy reacting with the steel of the car and not being able to remove the subframe again.
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teamalsoran
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Post Sun Feb 07, 2010 11:28 pm

if you fit the bushes upsidedown the beam will go back in higher, i take things one step further and trim about 10mm off the top of the beam to get it to sit even higher, although in doing so you need to shorten the bushes and swap the brackets that bolt to the sill over side for side and then bolt them on upside down, doing so allows to to considerably lower the car before rear camber becomes too excessive