Powerflex Black Rear Subframe Inserts

[BruceWarne]

The black inserts are harder than the yellow ones.

All the good things people say about the M3 bushings seem to apply.

I've never driven a car with the M3 bushings, but I can hardly imagine that those can be much better than this.

Very little if any increase in NVH.

You can get these for $82/side on ebay.

[PrematureApex]

Any reason you didn't just put this into your Powerflex Insert thread 5 threads down?

Oh wait, you already did.

[BruceWarne]

Originally Posted by PrematureApex

Any reason you didn't just put this into your Powerflex Insert thread 5 threads down?

Oh wait, you already did.

Yeah, because that thread was already too long for anyone looking for some quick info 2 years from now.

Anyway, so these have been on the car for about a week now.

I'm still very impressed. I think the positive changes these made are up there with changing to BMW PS. Also interesting: You know that funny thing these car do when you do a quick shift from 1st to 2nd and get on the power hard (a very scary form of uncontrolled oversteer - someone else posted something about it recently). It's gone.

[dcaron9999]

About to order rear bushing inserts, but hesitating between Powerflex and Whiteline. Why did you get the more expensive Powerflex - are they much more durable, stiffer, for a dual-purpose daily driver + track car? I know that ideally, M3 bushings plus 8 hour labor are the ultimate solution, but not ready to throw $1000 at labor and parts.

So I may start off with DIY inserts, and see how that goes and lasts ...

[dcaron9999]

Got this note from the Design and Development manager at PowerFlex:

"The rear bushes give the best control of the subframe but are harder to fit (getting the old bush out is the worse part!) and can add to the NVH in the Black material.

The Inserts do work very well and block some of the movement with reported improvements over the standard car, if the original bushes are badly worn best to change the bushes.

Both options have advantages over the standard set up, obviously for the best control of the subframe in track conditions is the complete black series bushes.

The yellow bushes still offer a firmer location of the subframe over the standard bush and would be more comfortable on the road."

[nato-main-man-5am]

Originally Posted by BruceWarne

The black inserts are harder than the yellow ones.

All the good things people say about the M3 bushings seem to apply.

I've never driven a car with the M3 bushings, but I can hardly imagine that those can be much better than this.

Very little if any increase in NVH.

You can get these for $82/side on ebay.

Which vendor did you go with on ebay? I'm only seeing the yellow ones....