polyurethane bushes?? experiences

[tiger18]

hi guys im gonna rebuild all my rear end suspension,,, 6 new mazda pillow balls and replace all the rubber bushes. Now im looking into maybe powerflex polyurethane..
What im wanting to know is how is the ride quality on poly,, i dont want the car to get stupidly hard or vibrate,,, how much a difference is poly over OE rubber bushes.
Can anybody help who has polyurethane bushes fitted?

[gonzoninja]

I\'ve just had powerflex bushes fitted all round my car, and thank god all that horrible squeaking it was making has gone! EDIT: I mean from the old bushes, not the powerflex ones squeaking!!!

To be honest I don\'t think it makes too much difference to the ride (can\'t tell they also lowered my car at the same time and fitted new top mounts).

It feels a lot tighter when driving though.

[efiniste]

Shameless plug.

Poly bushes group buy

[Grizzly]

I personaly don\'t rate them, Might be a bit difrent with Fd\'s but on my T2 i went through a few sets in the 3 years the car was on the road, becouse they are hard they tend to elongate the Holes and go small in the Mountings, Also the Noise they Make gets on your Nerves after a bit.

I now only use Mazda or Mazdaspeed Bushes, I\'ve never had a problem with them (apart from being a bit expencive)

[tiger18]

think ill just stick with stock mazda all round,,, tried and tested no hassles,,,just maybe a bit more expensive:Talking1

[stylus350]

I personaly don\'t rate them, Might be a bit difrent with Fd\'s but on my T2 i went through a few sets in the 3 years the car was on the road, becouse they are hard they tend to elongate the Holes and go small in the Mountings, Also the Noise they Make gets on your Nerves after a bit.

I now only use Mazda or Mazdaspeed Bushes, I\'ve never had a problem with them (apart from being a bit expencive)

Were the ones you tried powerflex? Ive held a couple of powerflex ones and they seemed soft in comparison to the solid poly type which are hard and can be noisey,but they are harder than stock. I am looking to replace FD ones so watching this thread. Any other input?

[cruiser]

I talked to some racer in USA, as I was about to install some jimlab or delrin bushings, and he said that these bushes are not appropriate for the rear suspension, is it doesnt move in just one direction.

His reply:
Personally I don\'t think solid (nylon, delrin etc) bushings are a good solution. The bushing often needs to allow more than one degree of movement so you need rubber, urethane or a solid rod end heim joint (which isn\'t a practical solution for a street vehicle). Look at the rear suspension for instance. The trailing arm locates the fore/aft position of the wheel. Since the trailing arm swings through an arc the wheel will move slightly forward and back as the suspension moves. This means the lower a-arm not only swings, it moves slightly fore and aft as it does so. The lower a-arm also swings through an arc from its inner bushing. As it swings the end of the trailing arm must move very slightly side to side since it\'s connected to the lower a-arm. The stock rubber bushings (or anything with some "give") allow for this deflection. Solid ones do not. At worst solid non-spherical bushings will bind or reduce suspension compliance when under load, and at best they will wear quickly due to that fact that there\'s more going on than most people realize. At the front suspension this isn\'t a problem.

I go through a set of rear pillowballs every couple seasons (20+ autox and a half dozen track days every season). I spend so much time under hard braking on race rubber that I wear pillowballs out quickly. The ones in the rear uprights wear out first because they have to resist the brake reaction forces. I go through the pillowballs in the uprights twice as fast as the pillowballs at the trailing arm. I wear out the smaller outer toe link bushing about every 2-3 seasons as well. The larger inners seem to hold up longer; I\'ve only replaced them once.

I run stock bushings everywhere with the exception of Mazdaspeed trailing arm bushings. These are rubber bushings which are slightly firmer than stock. They\'re available through Mazdaspeed Motorsports. I\'ve run aftermarket toe links in the past and don\'t recommend them. They offer no real advantage and wear out faster than stock. I\'ve tried nylon trailing arm bushings as well and wore them out quickly. I didn\'t see any real gains from them either. My advice is stick with stock bushings but realize if you race often you will need to replace parts due to wear. That\'s how life is. The only solid bushing I would run would be in the diff but at my stock power levels I don\'t have issues with the stock diff bushings and I like that the stock ones are quiet. Keep the engine and diff mounts in good shape and you\'ll have few axle tramp problems.

[Grizzly]

Were the ones you tried powerflex? Ive held a couple of powerflex ones and they seemed soft in comparison to the solid poly type which are hard and can be noisey,but they are harder than stock. I am looking to replace FD ones so watching this thread. Any other input?

I tried two diffent Types (Energy (red) and i think the other was Superpro (blue) they both where the same, If you give it some abuse (Track days and such) you will very soon find they start to deform.

I would say mine where good for a Year before they started to go out of shape, the Squeeking started problerly a month after i fitted them (the grease i used to fit them was pushed out).

[Grizzly]

I talked to some racer in USA, as I was about to install some jimlab or delrin bushings, and he said that these bushes are not appropriate for the rear suspension, is it doesnt move in just one direction.

His reply:
Personally I don\'t think solid (nylon, delrin etc) bushings are a good solution. The bushing often needs to allow more than one degree of movement so you need rubber, urethane or a solid rod end heim joint (which isn\'t a practical solution for a street vehicle). Look at the rear suspension for instance. The trailing arm locates the fore/aft position of the wheel. Since the trailing arm swings through an arc the wheel will move slightly forward and back as the suspension moves. This means the lower a-arm not only swings, it moves slightly fore and aft as it does so. The lower a-arm also swings through an arc from its inner bushing. As it swings the end of the trailing arm must move very slightly side to side since it\'s connected to the lower a-arm. The stock rubber bushings (or anything with some "give") allow for this deflection. Solid ones do not. At worst solid non-spherical bushings will bind or reduce suspension compliance when under load, and at best they will wear quickly due to that fact that there\'s more going on than most people realize. At the front suspension this isn\'t a problem.

I go through a set of rear pillowballs every couple seasons (20+ autox and a half dozen track days every season). I spend so much time under hard braking on race rubber that I wear pillowballs out quickly. The ones in the rear uprights wear out first because they have to resist the brake reaction forces. I go through the pillowballs in the uprights twice as fast as the pillowballs at the trailing arm. I wear out the smaller outer toe link bushing about every 2-3 seasons as well. The larger inners seem to hold up longer; I\'ve only replaced them once.

I run stock bushings everywhere with the exception of Mazdaspeed trailing arm bushings. These are rubber bushings which are slightly firmer than stock. They\'re available through Mazdaspeed Motorsports. I\'ve run aftermarket toe links in the past and don\'t recommend them. They offer no real advantage and wear out faster than stock. I\'ve tried nylon trailing arm bushings as well and wore them out quickly. I didn\'t see any real gains from them either. My advice is stick with stock bushings but realize if you race often you will need to replace parts due to wear. That\'s how life is. The only solid bushing I would run would be in the diff but at my stock power levels I don\'t have issues with the stock diff bushings and I like that the stock ones are quiet. Keep the engine and diff mounts in good shape and you\'ll have few axle tramp problems.

This sounds quite accurate.

[stylus350]

This sounds quite accurate.[/QUOTE

Yes sounds like a man who knows. He did say

\'Personally I don\'t think solid (nylon, delrin etc) bushings are a good solution. The bushing often needs to allow more than one degree of movement so you need rubber, urethane or a solid rod end heim joint \'

Isnt urethane what powerflex are made of?

[Grizzly]

Yep. I would suget sticking with Stock or Mazdaspeed.

[Grizzly]

Isnt urethane what powerflex are made of?

Ok, To put it in a Nut shell, a polly bush is alot harder than Rubber, this causes a problem where Rubber takes an Impact or load deforms and then reforms to its origanal shape, the Polly bush does\'nt do this. What is does is take the Impact or load and try to hold its shape (becouse its harder) ok this keeps the Suspension Geo closer to the pre set specs but the Rubber Bush acts like a Damper and takes the Shock out of the blow, Polly bush does\'nt reform like a Rubber Bush so after a few Hits it will start to deform, thats why if you buy Proper Bushes (Like Mazdaspeed of feed) they are still rubber lined but the steel cases are alot thicker so there is less rubber (in turn less movement)

If you have seen a Polly Bush close up they are very Cheaply made when you put it next to say a feed bush, at the end of the day you get what you pay for.

[Grizzly]

This sounds quite accurate.[/QUOTE

Yes sounds like a man who knows. He did say

Sorry you did\'nt understand what i ment, If you go on the US forums you will quickly find out alot of people don\'t know what there talking about and just pass on other peoples Opinions rather than what they have personaly Experianced.

[pdtaylor18]

I have powerflex bushes fitted and have so far heard nothing from them in terms of noise and the handling has a marked improvement, not massive but its better. To me it was the most cost effected way of replacing worn bushes and no way could i afford the mazda or mazdaspeed replacements. For someone who does not race, the powerflex do the job for the milage we do in them per year.

[Grizzly]

If you don\'t mind me asking what milage do you do and how do you treat them? (Trackdays etc?)

TBH they proberly would make a good stock road replacments but if you are thinking of Track time i would go stock.