Flo-Flex poly bushes - any good?

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fearlessphil
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Post Sat Oct 13, 2012 8:52 am

ive got my rear end off at the min just been blasted and painted now im about to buy poly bushes for it i was going to go for power flex but ive just seex that flo-flex are about half the price! does any one have any experience with the flo-flex stuff is it worth a go?
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HJG-E30
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Post Sat Oct 13, 2012 10:38 am

Personally I'd just put OEM bushes on the car. Yea poly bushes may be more durable, but you're extremely unlikely to still be in ownership of the car when new OEM bushes begin to perish
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Post Sat Oct 13, 2012 11:12 am

I would not suggest polybushes of any kind for the rear axle carrier bushes on a road car.Trackday fun car,maybe...the OEM type rubber bush is designed to add a touch of rear wheel steer,making the car more controlable on the road.Having the arse snap out on track is fine,you have a large,empty run off area to spin into...

Poly bush the trailing arms and the diff carrier,and the ARB too!
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Post Sat Oct 13, 2012 12:33 pm

Do not polly bush the diff carrier

New OEM Z3M bush is the best option.
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Brianmoooore
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Post Sat Oct 13, 2012 1:18 pm

daimlerman wrote: Poly bush the trailing arms and the ARB too!
Wouldn't use the here either - the OE bushes produce a zero friction bearing, whereas poly bushes introduce friction where it's not wanted.
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Post Sat Oct 13, 2012 2:04 pm

Brianmoooore wrote:
daimlerman wrote: Poly bush the trailing arms and the ARB too!
Wouldn't use the here either - the OE bushes produce a zero friction bearing, whereas poly bushes introduce friction where it's not wanted.
Poly bushes that I have used for the trailing arms have a stainless steel bush,the poly just fills the void,so zero friction...
ARB bush mirrors OEM in design,but in a material that will outlast OEM,but does,however,transmit noise.
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Brianmoooore
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Post Sat Oct 13, 2012 2:12 pm

daimlerman wrote:
Poly bushes that I have used for the trailing arms have a stainless steel bush,the poly just fills the void,so zero friction...
Unless it incorporates a roller bearing, then it introduces friction!
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Post Sat Oct 13, 2012 2:30 pm

i was going to use the z3m diff bush and standard for the ARB just polly bush the rear beam and trailing arms its a fun / fast road (we have no speed limit on the isle of man ) / track day car that i am just about to restore (if i ever find some where to do it where the rent wont cripple me! As the main beam has to be taken off to change the bushes i want to do them in poly so they last but you got me thinking about the trailing arms now, does anyone know the life span of the trailing arm bushes? if its upwards of 10 years i may go OEM
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Post Sat Oct 13, 2012 2:45 pm

Brianmoooore wrote:
daimlerman wrote:
Poly bushes that I have used for the trailing arms have a stainless steel bush,the poly just fills the void,so zero friction...
Unless it incorporates a roller bearing, then it introduces friction!
:bow:

On the two E30's that I have restored with my own hands :o:

I found 'side to side' movement on the trailing arm bushes.Fitting poly bushes just gave me a free 'up and down' movement,now,I a'int no engineer,but a OEM bush would have given me an 'up and down' movement that would have returned like an Assie boomerang to the position it was bolted to,therefore causing tension in the bush as it moved,the poly bush,with it's stainless centre,eliminates this twisting action....
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greg124
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Post Sat Oct 13, 2012 5:38 pm

Mr. Moore,

if as you stated above OE bushes produce a zero friction bearing, and you only get zero friction with a roller bearing, are you seriously telling us that the OE bushes consist of a roller bearing?
Schadenfreude - the German's haven't got a word for that.
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Post Sat Oct 13, 2012 11:25 pm

The OE bearing is rubber and is frictionless. There is no hysteresis with the twisting of a rubber bush, so it is frictionless. The twisting of the rubber just adds to the rate of the springs.
In a poly bearing, one surface slides on another, whether that substance is plastic, stainless steel or whatever, there is friction and hysteresis. I.E. If you compress the suspension with a calibrated jack, the pressure to compress it to a certain point will be higher as it compresses the suspension than it will be when the suspension has drooped to the same point as the jack is let down.
Even a roller bearing is not entirely frictionless, just a lot closer to it than one bush sliding on another.
Regarding the life of OE bushes; a pair of genuine beam bushes should easily last ten years, and I've never found a set of OE trailing arm bushes in unserviceable condition yet.
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Post Sat Oct 13, 2012 11:36 pm

poly bushes will shake your fillings out .
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Post Sat Oct 13, 2012 11:39 pm

magpie wrote:poly bushes will shake your fillings out .
Do you have Poly bushes then Mick???
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Post Sat Oct 13, 2012 11:47 pm

no,all my bushes are brand new oem ,M3 eccentrics up font with Dan's void fillers and standard trailing arms taking care of the rear lol.

who needs poly's . i wanted to build a comfortable fast car that handles well on the road .

gold fillings rav :chuckle:
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Post Sat Oct 13, 2012 11:49 pm

polybushes =Fail

nothing wrong with Lemforder replacements, they take a good hammering and cost less :mad:
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Post Sat Oct 13, 2012 11:52 pm

Fook off, poly bushes are fine. :D
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Post Sat Oct 13, 2012 11:53 pm

On a road car, the only bush that i would use polly on is an anti roll bar bush as there is virtually no extra vibration caused and the OE rubber one's hole in which the bar passes through wears oval through friction of the the bar twisting. A polly one will wear slower.

Never use a polly diff bush for two reasons, one because it transmits vibration from the final drive and two because the diff bush triangulates the rear axle mounting which needs to move for the reasons all ready mentioned.

Nearly all trailing arm bushes i have seen have been fine even after 15-20 years!
I can think of two E30's where they needed replacing, on was my mates old 320iS in which the Left hand outer bush had completely deteriorated to the point that the trailing arm moved enough for the inside of the 8J Alpina with 225 tyre, to touch the exhaust rear box!

The car had done approx 210,000KM. We rebushed the whole car with OEM.

The other was Felix's old Alpina C2 2.5 which had the most rusty, f*cked worn out suspension i have ever seen on an E30 and the trailing arm bushes were very old and cracked but these still didnt have excesses play in them!
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Post Sat Oct 13, 2012 11:53 pm

Rav335uk wrote:Fook off, poly bushes are fine. :D
for your turd they are :D
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Post Sat Oct 13, 2012 11:55 pm

e30topless wrote:
Rav335uk wrote:Fook off, poly bushes are fine. :D
for your turd they are :D
Will be. :D
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e30topless
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Post Sun Oct 14, 2012 12:01 am

bss325i wrote:On a road car, the only bush that i would use polly on is an anti roll bar bush as there is virtually no extra vibration caused and the OE rubber one's hole in which the bar passes through wears oval through friction of the the bar twisting. A polly one will wear slower.
Bazzle it does take around 15-20 years to go oval :D

OEM FTW, why pay more to have poly bushes and make your turd ride shite.. I have never worked that out :P
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Post Sun Oct 14, 2012 12:06 am

e30topless wrote:
bss325i wrote:On a road car, the only bush that i would use polly on is an anti roll bar bush as there is virtually no extra vibration caused and the OE rubber one's hole in which the bar passes through wears oval through friction of the the bar twisting. A polly one will wear slower.
Bazzle it does take around 15-20 years to go oval :D

OEM FTW, why pay more to have poly bushes and make your turd ride shite.. I have never worked that out :P
I did say that the ONLY polly bush that is ok to use is the anti roll bar bushes, they will NOT give any detriment to the ride quality.

The bushes that come with eibach and H&R roll bar kits are polly.
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Post Sun Oct 14, 2012 7:11 am

The ones on my chrome turd were fooooooked

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Replaced withh OEM

:D
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e30topless said : Proper BMW's have 4 headlights, last of the run was the E30 and E34/E32 anything after that is just complete shite