Polybush all standard new bushes
Discussion
Technical question.
I am currently preparing a Boxster 986S for track day use.
Not going mad as we all know, this is a fun thing. Car needs quite a bit of work, (to say the least) and is progressing well .I have had to renew all the coffin arms, (like a lower wishbone) and these have an inner pivoting bush and an outer bush where a control arm bolts on. There is also a rear control arm with a rubber bush to the chassis on the rears.
I’ve had to renew all these components as the existing 21 year old bushes were seized solid on the pivoting bolts and were far past their best.
Looking at all the new components with their new very firm rubber bushes in place I am wondering whether to continue with my plan of pressing these out and renewing with polybushes.
I have already bought the new polybushes, unopened packs, so I guess I could return them. I have black for the inner pivoting bushes and the standard purple, (because black aren’t available for the outer bush where the control arm attaches.
Question: at this stage, am I wasting time fitting the polybushes? Will the benefit, be so meniscal that I will barely notice over the new rubber bushes.? This will be pressing out 10 brand-new bushes and of course fitting the polybushes.
Car will be running standard engine, different exhaust, track brake pads, R888’s , polybushed ARB’s and some lighter seats.
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I am currently preparing a Boxster 986S for track day use.
Not going mad as we all know, this is a fun thing. Car needs quite a bit of work, (to say the least) and is progressing well .I have had to renew all the coffin arms, (like a lower wishbone) and these have an inner pivoting bush and an outer bush where a control arm bolts on. There is also a rear control arm with a rubber bush to the chassis on the rears.
I’ve had to renew all these components as the existing 21 year old bushes were seized solid on the pivoting bolts and were far past their best.
Looking at all the new components with their new very firm rubber bushes in place I am wondering whether to continue with my plan of pressing these out and renewing with polybushes.
I have already bought the new polybushes, unopened packs, so I guess I could return them. I have black for the inner pivoting bushes and the standard purple, (because black aren’t available for the outer bush where the control arm attaches.
Question: at this stage, am I wasting time fitting the polybushes? Will the benefit, be so meniscal that I will barely notice over the new rubber bushes.? This will be pressing out 10 brand-new bushes and of course fitting the polybushes.
Car will be running standard engine, different exhaust, track brake pads, R888’s , polybushed ARB’s and some lighter seats.
They definitely work better & last better.
Personally I have done 3 x track day cars now (different to yours) and with each I have gone full poly-bush & the benefits have definitely been noticeable over worn originals.
Whether the same would be true over good OE bushes I have no idea, but if I were in your position I would carry on as you are.
Personally I have done 3 x track day cars now (different to yours) and with each I have gone full poly-bush & the benefits have definitely been noticeable over worn originals.
Whether the same would be true over good OE bushes I have no idea, but if I were in your position I would carry on as you are.
Are you going genuine Porsche or spurious?
I changed my lower wishbones with good looking new febi ones and they didnt last 6months.
If going new porsche genuine you should get good service out of the oe item, if going spurious I'd use the polybushes so you dont have to revisit the job.
I changed my lower wishbones with good looking new febi ones and they didnt last 6months.
If going new porsche genuine you should get good service out of the oe item, if going spurious I'd use the polybushes so you dont have to revisit the job.
Not genuine Porsche. I have bought a complete set of. Mahle lower arms. These are generally good quality replacements.
I feel bad cutting out the new bushes, especially the outer bushes as these have a steel sleeve. The inner ones would be easy enough I guess.
Just wondering whether I should put it together standard. Will probably do about 6–8 Track Days in a year, and as they are all being assembled like new will come apart very quickly if I need to then change the bushes.
My mood swings, I think due to how cold it is in the garage at the time of thought!
I feel bad cutting out the new bushes, especially the outer bushes as these have a steel sleeve. The inner ones would be easy enough I guess.
Just wondering whether I should put it together standard. Will probably do about 6–8 Track Days in a year, and as they are all being assembled like new will come apart very quickly if I need to then change the bushes.
My mood swings, I think due to how cold it is in the garage at the time of thought!
E-bmw said:
They definitely work better & last better.. .
.. than 20+ year old originals.This is the problem, everyone compares their new, aftermarket stuff with knackered old stuff on their old whatever and proclaims it to be a huge improvement. I've fallen for it myself previously.
However - I've e now done a full, front to back, full chassis, arms, links etc type job on two cars, one of which was a Boxster.
The car, ostensibly had nothing wrong with it. To most people it was fine. No knocks, bangs, leaks, etc.
However let me assure you that once I'd replaced all that "fine" original kit, the difference was remarkable. Such better body control, tighter, quieter, more communicative.
Honestly. Cutting up brand new arms is madness. Send the poly bushes back. Drive it.
snotrag said:
.. than 20+ year old originals.
This is the problem, everyone compares their new, aftermarket stuff with knackered old stuff on their old whatever and proclaims it to be a huge improvement. I've fallen for it myself previously.
However - I've e now done a full, front to back, full chassis, arms, links etc type job on two cars, one of which was a Boxster.
The car, ostensibly had nothing wrong with it. To most people it was fine. No knocks, bangs, leaks, etc.
However let me assure you that once I'd replaced all that "fine" original kit, the difference was remarkable. Such better body control, tighter, quieter, more communicative.
Honestly. Cutting up brand new arms is madness. Send the poly bushes back. Drive it.
Slightly confused. Aren’t you contradicting yourself?This is the problem, everyone compares their new, aftermarket stuff with knackered old stuff on their old whatever and proclaims it to be a huge improvement. I've fallen for it myself previously.
However - I've e now done a full, front to back, full chassis, arms, links etc type job on two cars, one of which was a Boxster.
The car, ostensibly had nothing wrong with it. To most people it was fine. No knocks, bangs, leaks, etc.
However let me assure you that once I'd replaced all that "fine" original kit, the difference was remarkable. Such better body control, tighter, quieter, more communicative.
Honestly. Cutting up brand new arms is madness. Send the poly bushes back. Drive it.
Or have I read that wrongly?
Imho polybushes are at their best when there's very little movement in the joint, otherwise in a road car they tend to squeak (even when lubed on assembly), and wear pretty quickly despite the claims.
So now I'll use them for fairly static applications, then use good OEM metallastic for joints that have pretty big movements instead.
Once thing that's absolutely worth it is engine and gearbox mounts as said, and I've had good experiences with the inserts that some mounts can be upgraded with instead of replacement.
So now I'll use them for fairly static applications, then use good OEM metallastic for joints that have pretty big movements instead.
Once thing that's absolutely worth it is engine and gearbox mounts as said, and I've had good experiences with the inserts that some mounts can be upgraded with instead of replacement.
Coincidentally, just been reading about the polybush insert for the engine mount for the Boxster .
I was just looking at the prices of rear engine mounts, nearly 400 pounds the pair, ridiculous but I guess these are OE. Spyder Performance do mounts at about 90 quid each but they are bound to be pattern. I’m going to speak to Design 911 tomorrow and ask their advice.
I was just looking at the prices of rear engine mounts, nearly 400 pounds the pair, ridiculous but I guess these are OE. Spyder Performance do mounts at about 90 quid each but they are bound to be pattern. I’m going to speak to Design 911 tomorrow and ask their advice.
I'd be tempted to get the pattern mounts and fit these, or even in black series strength if it's more track and less road-biased: https://www.powerflex.co.uk/product-details/Front+...
phazed said:
Slightly confused. Aren’t you contradicting yourself?
Or have I read that wrongly?
My point - you do not need to 'upgrade'.Or have I read that wrongly?
You just need to *fix*.
Bog standard, OE or OE equivalent, such as the kit the OP has already bought, is so, so, so much bettter than than 20 year old originals. Without the drawbacks of 'upgraded' polybushes, such as the squeaking mentioned above.
I get your point.
Sadly, I never drove the car more than 100 yards before taking it apart but all the suspension was original 22 year old and has now been or in the process of being replaced, at least 95% anyhow! I have only left the front and the rear tuning forks as original but of course the bushes were they bolt on to the lower arms are all new.
Suspension units are Bilstein B8’s with 30 mm lower and stiffer H&R springs.
Plan is to remove about 100 KG from seat change, the usual spare wheel and ancillaries removed without going too mad. Should be good.
Sadly, I never drove the car more than 100 yards before taking it apart but all the suspension was original 22 year old and has now been or in the process of being replaced, at least 95% anyhow! I have only left the front and the rear tuning forks as original but of course the bushes were they bolt on to the lower arms are all new.
Suspension units are Bilstein B8’s with 30 mm lower and stiffer H&R springs.
Plan is to remove about 100 KG from seat change, the usual spare wheel and ancillaries removed without going too mad. Should be good.
honestly - rebuild it all with what you have.
Its documented on here but I did a 2002 with 120k odd miles on it - used all decent brand OE equivalent stuff, Mahle, Febi, Meryle, TRW etc like you have. coffin arms, trailing arms, droplinks, etc etc new bilsteins, and it was superb (on track too). And as you've said, once its all been off once, it will ocme apart easily later if you wanted. I just think its mad to cut out all the brand new rubber bushes you've just paid for.
Its documented on here but I did a 2002 with 120k odd miles on it - used all decent brand OE equivalent stuff, Mahle, Febi, Meryle, TRW etc like you have. coffin arms, trailing arms, droplinks, etc etc new bilsteins, and it was superb (on track too). And as you've said, once its all been off once, it will ocme apart easily later if you wanted. I just think its mad to cut out all the brand new rubber bushes you've just paid for.
Apart from obviously being the most simple solution, I think I will go down that route. I will leave the poly bushes on the shelf. They won’t go to Waste. I also have a really nice standard RS60 which I have used on Track Days but decided it was Too nice as it is a keeper. Hence the purchase of this very cheap 3.2.
Out of interest how did your 986 behave on Track compared to your Elise? I’m guessing probably about 80%.
RS60.
Coincidentally, the 3.2, 986 is the same colour! Just a coincidence. Complete with spoiler that won’t go down, roof that won’t go down and windows that won’t go down, seems to have a common theme this car!
Out of interest how did your 986 behave on Track compared to your Elise? I’m guessing probably about 80%.
RS60.
Coincidentally, the 3.2, 986 is the same colour! Just a coincidence. Complete with spoiler that won’t go down, roof that won’t go down and windows that won’t go down, seems to have a common theme this car!
Just to add a little more confusion...
My Cayman is polybushed all round (including gearbox mounts but not the engine mount). It doesn't squeak and apart from a little more low level vibration, I have experienced no drawbacks at all.
My race car (not a Porsche) is also fully polybushed and (on track at least) that does not squeak either.
If you are building this for track days, then I would happily fit polybushes. If it is primarily a road car then I wouldn't bother because a) you won't need them and b) the rubber bushes do dampen those vibrations.
An added benefit of the Powerflex bushes is that you can also fit camber adjustable bushes to the front to get a little more front camber (my Cayman runs -2 all round).
My Cayman is polybushed all round (including gearbox mounts but not the engine mount). It doesn't squeak and apart from a little more low level vibration, I have experienced no drawbacks at all.
My race car (not a Porsche) is also fully polybushed and (on track at least) that does not squeak either.
If you are building this for track days, then I would happily fit polybushes. If it is primarily a road car then I wouldn't bother because a) you won't need them and b) the rubber bushes do dampen those vibrations.
An added benefit of the Powerflex bushes is that you can also fit camber adjustable bushes to the front to get a little more front camber (my Cayman runs -2 all round).
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