Powerflex bushes vs myle-hd

[mr nurburgring]

he also says stick with meyle hd or OEM

So?
Maybe he doesnt like the extra performance. Maybe he has the driving style of a granny...
If you have, powerflex products arent for you. They're ment for people who attain a sporty driving style.

PMSL - so your saying that people who go to the ring etc who drive it like they stole it are in the wrong for choosing meyle bushings over Powerflex?

Power flex offer no extra performance over good Oem bushes on a road car or even a car you use on occasionally the track.
That lollipop bush is designed to absorb forces that are applied through the wheels, it’s not just a pivot point, if you solidly mount the rear of that arm those forces have to be absorbed somewhere, those ball joints are going to take a pounding.
Road noise is also transmitted through solid bushes, I tried powerflex years ago and removed them after a week in favour of oem.
I don’t drive like a granny on track, many uk tracks and the ring of course in 9 mins on oem stuff, nothing broken.

Fit what you want, it’s your car, but if you believe your going to gain extra performance you’re mistaken. Only negatives in my experience.

 

[jamie_z4]

So?
Maybe he doesnt like the extra performance. Maybe he has the driving style of a granny...
If you have, powerflex products arent for you. They're ment for people who attain a sporty driving style.

PMSL - so your saying that people who go to the ring etc who drive it like they stole it are in the wrong for choosing meyle bushings over Powerflex?

Power flex offer no extra performance over good Oem bushes on a road car or even a car you use on occasionally the track.
That lollipop bush is designed to absorb forces that are applied through the wheels, it’s not just a pivot point, if you solidly mount the rear of that arm those forces have to be absorbed somewhere, those ball joints are going to take a pounding.
Road noise is also transmitted through solid bushes, I tried powerflex years ago and removed them after a week in favour of oem.
I don’t drive like a granny on track, many uk tracks and the ring of course in 9 mins on oem stuff, nothing broken.

Fit what you want, it’s your car, but if you believe your going to gain extra performance you’re mistaken. Only negatives in my experience.

Finally,

 

[GuidoK]

That lollipop bush is designed to absorb forces that are applied through the wheels, it’s not just a pivot point, if you solidly mount the rear of that arm those forces have to be absorbed somewhere, those ball joints are going to take a pounding.
Road noise is also transmitted through solid bushes, I tried powerflex years ago and removed them after a week in favour of oem.

Powerflex aren't solid bushings. Why are you under the impression of that?
That simply isnt true. You're giving false information here!
Also the road noise transmitted through the purple fcab powerflex bushings is imho negligible and certainly not so much that its an issue for a sportscar.

You also dont highlight the advantage polyurethane has over normal rubber, and that is that it keeps a consistent compliance over its lifetime used, which is something normal bushings dont do. Normal rubber gets softer and softer over its lifetime. The polyurethane bushings will keep their stiffness from new .
And that a certain stiffness is important from a performance pov comes from the fact that not all bushings in a car have the same stiffness. Also not OEM from new.
And therein lies also the last advantage, and that is that polyurethane bushings usually can be had in different stiffnesses, so you can tune your car to a use that is different than what the manufacturer had intended, which is the point/goal of all performance tuning products.
And because they keep their stiffness, you will keep that performance unlike rubber bushings that will degrade over time.

That a car will transmit more NVH as you make it stiffer and stiffer, is a no brainer. Therefore you can get polyurethane in different stiffnesses, and the shore80a is hardly any stiffer than a new OEM bushing.
The extra NVH you get from the purple powerflex fcab's is for instance in no way comparable to say the extra NVH you get from fitting a KW coilover set or H&R anti rollbars. And those are popular mods too so I dont see the problem
But if you find it that much of a problem with NVH, why on earth did you buy a z4?
That is in the beginning quite a stiff and sporty car. Why not buy an SLK, that has way less road noise/NVH in the beginning. Accordiing to your logic that must be the better car because of that!

And the stiffness of the purple fcab's (which we are talking about here), is not an issue regarding wear on the ball joints.
But of course after only one week of using them you must be the expert on that.....
But I call that an unfounded speculation, scaremongering if you like. If that was the case, the thousends of powerflex users would come with those reports....

 

[enzed4]

And therein lies also the last advantage, and that is that polyurethane bushings usually can be had in different stiffnesses, so you can tune your car to a use that is different than what the manufacturer had intended, which is the point/goal of all performance tuning products.
And because they keep their stiffness, you will keep that performance unlike rubber bushings that will degrade over time.

What powerflex bushings would you recommend for a replacement for OEM, for someone like me who I would probably classify as a 'sporty granny' driving style? You mentioned shore80a, is this the product? Thanks.

 

[GuidoK]

What powerflex bushings would you recommend for a replacement for OEM, for someone like me who I would probably classify as a 'sporty granny' driving style? You mentioned shore80a, is this the product? Thanks.

Shore 80a is the stiffness.
With powerflex these are coloured purple.
But you have an e89 which has a different front suspension setup, that has less issues with wear on the bushings. The main bushing that's so heaviy stressed and causes premature failing on the e46/e85 isn't present (or anything like it) on the e89 because of a totally different control arm setup.
For the front suspension on the e89 powerflex has 1 bushing, in shore95A (black). Here probably shore80A was way to weak.


However, anti rollbarbushings in shore80a (so the purple ones) are an easy upgrade if want to control rollover in corners a little bit, as those bushings in OEM variant are very soft.

 

[MrPT]

As above, I only PU’d my ARB bushes during a recent refresh, the rest are OEM. Seems to be a good compromise.

You can pick up smal blocks of Powerflex PU in a lot of tuning shops or at Goodwood FoS etc. The purple stuff is pretty squishy.

 

[enzed4]

What powerflex bushings would you recommend for a replacement for OEM, for someone like me who I would probably classify as a 'sporty granny' driving style? You mentioned shore80a, is this the product? Thanks.

Shore 80a is the stiffness.
With powerflex these are coloured purple.
But you have an e89 which has a different front suspension setup, that has less issues with wear on the bushings. The main bushing that's so heaviy stressed and causes premature failing on the e46/e85 isn't present (or anything like it) on the e89 because of a totally different control arm setup.
For the front suspension on the e89 powerflex has 1 bushing, in shore95A (black). Here probably shore80A was way to weak.


However, anti rollbarbushings in shore80a (so the purple ones) are an easy upgrade if want to control rollover in corners a little bit, as those bushings in OEM variant are very soft.

Thanks

 

[ben g]

I've had poly bushes fitted to front and rear anti roll bars, lollyypops and rear trailing arms for at least a few years now and there's no noticeable difference to me.

The ride was firm anyway, so unless you're a tame racing driver, my guess is you won't notice much, if any, difference in ride quality.

The advantage is that you can fit them and forget, as they will outlive the car. That for me was a massive plus, as I don't like replacing things that I've already replaced before (case in point being the front droplinks). I purchased cheap ebay droplinks to replace the factory set. These eBay items lasted 12 months before requiring replacement. I went for meyle hd this time around

 

[z4pilot]

If poly bushes were a no brainer upgrade with only benefits and no downsides, surely they would be fitted as OEM? My experience of "upgrades" is that there usually is a downside, it's just where your personal tolerance for it lies and whether the benefit outweighs the negative.

 

[enzed4]

If poly bushes were a no brainer upgrade with only benefits and no downsides, surely they would be fitted as OEM? My experience of "upgrades" is that there usually is a downside, it's just where your personal tolerance for it lies and whether the benefit outweighs the negative.

Like stubby aerials. Oh wait, there is no downside... (good radio reception is totally overrated) :lol:

 

[ben g]

If poly bushes were a no brainer upgrade with only benefits and no downsides, surely they would be fitted as OEM? My experience of "upgrades" is that there usually is a downside, it's just where your personal tolerance for it lies and whether the benefit outweighs the negative.

Polybushes are more expensive than rubber.

Cost is massive for vehicle manufacturers, unless you think they're charities and not businesses?

 

[Piper1]

If poly bushes were a no brainer upgrade with only benefits and no downsides, surely they would be fitted as OEM? My experience of "upgrades" is that there usually is a downside, it's just where your personal tolerance for it lies and whether the benefit outweighs the negative.

Polybushes are more expensive than rubber.

Cost is massive for vehicle manufacturers, unless you think they're charities and not businesses?

You beat me to it. Not to mention job security for the mechanic who replaces wear and tear items, and money back to manufactures of those service parts. There's a huge aftermarket demand out there for owners to customize their car using the platform that auto markers make of one car to fit for all.

 

[z4pilot]

If poly bushes were a no brainer upgrade with only benefits and no downsides, surely they would be fitted as OEM? My experience of "upgrades" is that there usually is a downside, it's just where your personal tolerance for it lies and whether the benefit outweighs the negative.

Polybushes are more expensive than rubber.

Cost is massive for vehicle manufacturers, unless you think they're charities and not businesses?

You beat me to it. Not to mention job security for the mechanic who replaces wear and tear items, and money back to manufactures of those service parts. There's a huge aftermarket demand out there for owners to customize their car using the platform that auto markers make of one car to fit for all.

I disagree. I fail to see that at the volumes that would be used by OEMs, poly bushes would be any more expensive than rubber, and the maufacturers couldn't give a stuff about the downstream mechanic that swaps out the bushes on your 70k miles tired suspension - all they are bothered about are whether the components they use survive the warranty period. They won't be manufacturing the bushes anyway, so there's nothing in it for them - how many people would actually go back to the dealership to have bushes replaced? Near enough zero would be my guess. So there has to be another reason why they aren't fitted from new, and I would guess that it's something to do with NVH.

 

[Piper1]

Polybushes are more expensive than rubber.

Cost is massive for vehicle manufacturers, unless you think they're charities and not businesses?

You beat me to it. Not to mention job security for the mechanic who replaces wear and tear items, and money back to manufactures of those service parts. There's a huge aftermarket demand out there for owners to customize their car using the platform that auto markers make of one car to fit for all.

I disagree. I fail to see that at the volumes that would be used by OEMs, poly bushes would be any more expensive than rubber, and the maufacturers couldn't give a stuff about the downstream mechanic that swaps out the bushes on your 70k miles tired suspension - all they are bothered about are whether the components they use survive the warranty period. They won't be manufacturing the bushes anyway, so there's nothing in it for them - how many people would actually go back to the dealership to have bushes replaced? Near enough zero would be my guess. So there has to be another reason why they aren't fitted from new, and I would guess that it's something to do with NVH.

Is that why there's such a mark up at a dealer for parts you buy there??? True a lot of oem parts are made by other manufactures such as Bosch for example but even so there are many people as the every day joe that doesn't tinker on their car and yes when in for an alignment if a dealer sees that bushes are gone needing replacing yes people do have the dealer change them out while getting the alignment done. I'm sure many on these boards do much of the work on their cars but that's still a fraction of actual z4 owners out there.

When it comes to volumes, if you got the highest quality of every part possible that is available today, the sticker shock alone would prevent most buyers. Or we'd all drive a koenigsegg
Truth is some things are done at the highest quality by the lowest bidder. Why do you think car company's out source parts. Because the simplest answer is it's cheaper that way.

Regarding nvh on the LCA bush I'm sure the adjustable camber plates I have produce more. I'll know for sure once I fit mine in few weeks time. There's always a sacrifice when going for true sport/track tune suspension and on any car manufactures will choose the balance to comfort to try and please the masses.

Look at how Ford designed the new GT stating that they designed it for track first road second. There's that nitch market that they are targeting not the mass market that the z4 is targeted to.

True manufactures look at the warranty period, wanting it to last least to then, but you also have recall issues that cut into profits when they come up loooong after a warranty expires especially when it comes to safety, I had a car that had a recall due to outsourced ball joints for the life of the car due to low quality that they continued to use the low quality outsourced company. After the second time in I decided to do them myself with a higher quality aftermarket and never had issues since.

Different situation all together and not sure how it hit the uk market but the takata airbag deal hit the US market by storm so do give the manufactures little credit in not having the mentality it's gotta run till 70k out of warranty miles then not give 2shits bout the consumer. There wouldn't be brand loyalty for anyone on anything if that were to happen.

 

[GuidoK]

So there has to be another reason why they aren't fitted from new, and I would guess that it's something to do with NVH.

Obviously, but you're forgetting that the e85 is build on the e46 platform.
That is a car that has to be suitable for families and their dog to go on vacation.
That design dna shimmers through to the e85. It's way to expensive for BMW to overhaul a suspension system. The z4 is a parts bin car, that's the only way BMW can get the business case profitable (and with the last z4 they even had to team up to do that).
And that means that you have a suspension system that has the nice cusioness from the e46, a D class family car.

If you look at sportscars that are designed from the ground up, you see that suspension geometries and design are completely different.
take for instance the simple mx5. I dont know if you've ever seen one from the underside, but that car has more in common with a ferrari or corvette than a bmw. And if you look in detail to suspension bushings (what we're talking about here), you see that they're way smaller and thinner. Less rubber means stiffer, because the stiffness of bushingings, provided the same material used, is inversely proportional to the rubber thickness surrounding it. And with the e85 its that rather big, 86mm rubber bushing, with a really think core , maybe 15mm or so.
Sportscars like the mx5, or for instance ferrari's, they have a much much thinner bushings.

And if you step up again, to no compromise cars like koenigsegg, most is solid ball links

But the z4 has that dna of a family sedan partly in its undercarriage, and making the rubber in the bushing a little bit stiffer is a way way easier and cheaper method than casting a custom made lollipop and fitting a thinner, more sportscar style normal rubber bushing.

But if you dont feel the difference in added steering response by fitting a slightly stiffer bushing, these mods arent for you.
It thakes a certain kind of owner that expects certain things of his car to choose for poly bushings, and that goes for all performance tuning products.

 

[GuidoK]

Is that why there's such a mark up at a dealer for parts you buy there???

This is an interesting example of dealer/BMW markup:

Hydraulic belt tensioner assembly for m54 engine.

OEM is INA germany

partnumber 11287838797
Dealerprice is € 213,19 incl VAT (sorry, cant look up dealerprices in pounds)

This assembly is for sale at pkwteile. Its from INA, Only the BMW logo's on the castings is removed; they place a little insert in the casting machine that blanks out the bmw logos:
https://www.pkwteile.de/ina/2386289
€ 40,90. That means that the BMW part is 421% more expensive......
Dont forget, the part at PKW teile is also sold with profit, not only profit for INA but also profit for pkwteile.

So yes, profit on carparts is very very VERY lucrative.

I think what most people forget, is that we as end users aren't BMW customers. The dealerships are!
So BMW is mainly concerned with making cars that last their warranty period. After that, the interest for BMW lies with the dealers, not the end users.

 

[z4pilot]

But if you dont feel the difference in added steering response by fitting a slightly stiffer bushing, these mods arent for you.
It thakes a certain kind of owner that expects certain things of his car to choose for poly bushings, and that goes for all performance tuning products.

Ah ok, I think I understand... a certain kind of owner can feel the subtle differences through their contact points with the car; their hands, their feet and especially their arse. There's even an English phrase for it, 'through the seat of your pants'

So what were saying is it takes a special kind of arsehole to be able to tell the difference?

:wink:

 

[GuidoK]

So what were saying is it takes a special kind of arsehole to be able to tell the difference?

:wink:

No, it takes a certain kind of interest to feel the difference, not to be able to feel the difference.
There's a difference in that too

A person that bought his z4 to cruise around town and look pretty in the little sportscar probably doesn't take notice is those differences.

Just like a complete bushing refresh. A new OEM bushing also has huge improvement over an old bushing giving back that new car feel. But, as we all know, normal rubber bushings degrade pretty quickly. That 'new car feel' is pretty much gone after 15k miles so you can do that OEM bushing overhaul again if you want to keep that feel.
With polyurethane there is no degrading. The stiffness/compliency is kept over its entire lifespan.

 

[Chippie]

I fully re bushed an Audi S3 (8L) with polly bushes, which I had from new and there was definitely an increase in both the stiffness of the ride and noise/vibration over the OEM parts, especially the engine dogbone bushes which I did consider changing back to stock because of noise/ vibration travelling through the car, but in the end decided I could live with it (had that car 13 years and didn’t have to replace any of the bushes again), I will definitely be fitting polly bushes to the z4

 

[Magicarcher]

If poly bushes were a no brainer upgrade with only benefits and no downsides, surely they would be fitted as OEM? My experience of "upgrades" is that there usually is a downside, it's just where your personal tolerance for it lies and whether the benefit outweighs the negative.

You are right, but there are few things in life that only have benefits and no downsides. When it comes to engineering cars there are many attributes and targets that need to be met for the design to be approved. One such attribute is noise, vibration and harshness (NVH). Poly bushes are generally not good in that respect and I think the NVH engineers may not sign the car of in development (though I never cease to be amazed that BMW used runflats for so long!). They will also be testing the cars on many different tracks to cover as many intended uses as possible one being PAVE. I can't imagine how uncomfortable a poly bushed car would be on a PAVE track.

The requirements of users on this forum are likely to be very different from vehicle manufacturers, they may not be so bothered by NVH and are unlikely to drive at speed through a PAVE track.