PMS rear beam bearing

[scotiamr2t]

Currently refurbing a rear beam and have considered changing from powerflex black series bushes to the PMS bearing kit.

Anyone any experience with the PMS kit who could give a review or there experience with it?

 

[clio tyres]

changing from powerflex black series bushes

Is there any play in the powerflex?

 

[scotiamr2t]

Is there any play in the powerflex?

No, although the bushes do provide a fair bit of resistance to the beam moving vertically.

For some reason i feel the PMS kit would allow the beam to alot more freely in vertically, not convinced the beam should be as stiff to move as it is with the powerflex bushes.

 

[Steven103]

It does seem like quite a good idea tbh.

Cars with powerflex bushes in particular have loads of hysteresis / stiction. Sit in the boot, it goes down 40mm, get out and it only goes up 30mm type thing. Until you jump around a bit to help settle it. So that makes the spring/damper less effective which increases contact patch variation and reduces outright grip.

Can minimise this by loosening the beam & damper bolts and torquing them up at ride height not at full rebound. It’s just general good practice for assembling a car properly but I bet no garages other than main dealers (where it’s specifically written in the workshop manual) bother.

And then even though the bushes look really solid I bet if you put a go pro on or something you’d see a fair amount of lateral compliance when cornering on hot semi slicks on track. Adds toe in to the outside wheel and adds toe out to the inside wheel during cornering. Sounds helpful for stability but not helpful for consistency or outright grip.

 

[Steven103]

Obviously we’re into minimal gains so only do it after brakes, tyres, rarb etc

 

[scotiamr2t]

Obviously we’re into minimal gains so only do it after brakes, tyres, rarb etc

Those are all already taken care of, AP’s, semi slicks and full coilovers already fitted.