Hi guy I bought an 06 R53 two months ago with 95k on the clock. The car is awesome and I realize its known as a harsh ride quality to begin with especially since I am almost fully lowered on Megan coilovers. However my car is a ROUGH RIDE. I still have the original bushings in there. Should I replace everything with powerflex bushings and will this help out the rattles and vibrations??

Also like on WMW what set do I buy? Do I literally replace every bushing on all the control arms from front to back?

 

At 95K mi., pretty much every bushing needs help. Let your wallet be your guide but, IMHO, I'd do the front control arm and swaybar bushings first along with the inner and outer ball joints (they've just go to be shot as well), then evaluate your ride before you do more, like engine and tranny mounts, rear control arms, etc. If you do everything at once, you won't be able to appreciate what you've done. Just one note of caution: The more bushings you replace with polyurethane, the stiffer things get...which means more NVH, rattles, vibration, etc.

 

+1
The coilovers aren't doing you any favors with respect to NVH either.

 

Inspect or have your suspension inspected and replace parts as needed. Otherwise, swapping OEM bushings for poly will make your ride harsher. Also to note is that the Powerflex bushings for the rear are just inserts - they stiffen the existing OEM bushing.

Ditto on your coilovers and ride height. That is your biggest culprit. Welcome to the reality of suspension tuning tradeoffs...

 

NO
Powerflex bushings..AKA urathane as oppsed to the OEM RUBBER can make a ride worse...less isolated...gain is longer life and sometimes a FIRMER feel....
if the ride is HARSH and rough...it is the dampers and/or the springs...the rates are wrong or the dampers are worn or set for the wrong rate if adjustable.

 

I like my power flex LCA Bushings that I just put in. I don't think they made the ride any rougher, nor added any vibration. I do think it firmed up the steering wheel a bit, turn-in might feel slightly quicker. Accuracy of holding a line in a corner is better,... It didn't really wander much before -it just feels awesome now!

The power flex passenger side lower engine damper (dogbone) big and little end, along with the transmission mount did slightly increase the vibrations I feel in the cabin durring idle and initial take off from a stop -but that doesn't bother me much. I no longer keep loose coins in the cup holder, and it's fine by me.

I think what you're complaint is mainly about the harshness of bumps on the road, kaboom kaboom as you hit minor things like a man hole cover that appears to be level with the pavement anyway.

As mentioned above, that's all about your dampers and springs. Maybe the ride would not be as harsh if you could raise (adjust) the coil overs up a bit to give the suspension more travel? I don't really know enough about coil overs, but that might be worth investigating before you replace the suspension. Also,.. Do you have run flat tires?

I contemplate my future suspension. Mine is stock now, and the struts have enough miles that they are probably blown. Koni FSD might be the ticket for me, but I worry they might be too soft for spirited runs through the twisties. The FSD set up is probably the opposite end of the harshness-spectrum compared to your coil overs though.

 

My suspension setup is OEM except for KONI FSD struts and an ALTA sway bar upgrade. Compared to a soccer mom grocery getter, the Gen 1 ride conveys much more 'road feel' and can be misconstrued as being 'harsh'. English sports cars are renowned for their road feel. Thank goodness they are no longer renowned for their Lucas electrics.

 

Poly bushings are less forgiving and less pliable than the OE rubber bushings which is why they are preferred as an upgrade for street or mild track use. I did my Powerflex lower control arm bushings when I installed my lowering springs because one of the bushings was starting to get some slop in it. I've been very happy with how the steering feels and how controlled the car feels.
Unless you plan on going to the track very often, I don't know that I would just run out and buy the catalog and install all of it just yet. I would recommend taking your time and having each bushing checked and then replace as needed.
Also, have you thought about changing the damping on the Megan coilovers. They all have adjustable damping and are easily changed. This may help quite a bit if you soften them up.

 

OE bushings. As others said, higher durometer poly bushings will only increase NVH in comparison to OE. I'd put all poly on a track car, but not a DD. Just my $.02

 

Well...I have the Polly ones....ride is actually pretty good (pretty subtle at worst..but certainly not BETTER)...AND Koni FSD's....Results with stock springs and 16 are pretty good....when I have my 15' snows....about "normal" ride for many cars (not exactly what folks want in a MINI in some cases...)....bet you migt HEAR some extra noise with the polly when on a very worn piece of pavement or concrete...but having percise steering is a big gain compered to worn OEM rubber ones....
The biggest issue with the OEM bushings is they seem to last 70,000 miles or so....and are a pain to change...
I would put the polly ones in compered to the oem in an instant....
When a choice of different "hardness" polly is available...usually shown by color..get the softer for a street car...

 

The increase in NVH with Powerflex front control arm bushings is minimal, and they
locate the front wheel better than OEM.
The BIG advantage of the Powerflex bushings in this location, however, is the fact
that they last MUCH longer than the OEM ones. I went through OEM ones every
30K - 35K on our "wonderful" PA roads until I switched to the poly ones.

 

That's the main reason I switched.

This is the same design that all BMW 3 series from E30 to present use. The rear of the front control arm just stabs in to the bushing and that bushing is under a lot of stress with cornering loads and pot holes. The stock ones are garbage and failure prone.

 

Replacing only LCA bushings is different than his question of "Should I replace everything with powerflex bushings and will this help out the rattles and vibrations?? ". If you replaced your LCA, Rear Wishbone, Anti-Roll, Steering Rack, etc.. with higher durometer bushings, you'd have a very sharp, albeit NVH laden car, and it would not magically rid you of rattles / vibrations. Quite the opposite, I'd say.

 

What about your tires? Are you still running run-flats?

If you have good shocks, your car should not ride rough. If you install harder bushings....it's going to make it ride harder.

 

The ride is actually pretty nice on good quality pavement ( which is rare) I live in Los Angeles and the 405 is all concrete and it feels like the rattle and jarring you get when playing Forza going through the last turn at Sebring!

Btw I am on 17 X 7.5 ESM (old school mesh wheels) with high performance summer tires. Not run flats! And yes I think I should possibly raise the ride height up more, but it looks good and now I'm use to driving up ramps and speed bumps at 45 degree angle!

 

How far off the bump stops are you? That could be contributing to your issues. I'd say it's more likely that it's just a car with close to 100k miles lowered on coilovers. The ride isn't going to be pleasant.

 

In your case I can almost promise that it's the coils making it super harsh.

I've been looking at the Powerflex bushings as well in the "Street" Duro. I'm in Maine and the roads here are SO bad. Iv'e heard that poly can reduce tire noise, increase steering sensitivity as well as be longer lasting. One thing that was mentioned was that it could ride slightly stiffer. powerflex.com / howtochoose.aspx explains stiffness. It would seem as if 70a duro is probably about +20 duro over the stock bushings. I DO NOT want to get this done again at 40k more miles so that doesn't seem like a bad trade to me. Since shocks absorb most of the impact wouldn't bushings not really make a HUGE difference?

This seems like a pretty hot debate so yeah. Bring on the opinions I guess?

In the end I wanted the Street Bushings and some shock tower support plates to reduce "Shrooming"

As for you thedrunkensamurai... I would say get as squishy as possible if you want to have a more comfortable ride. OEM would likely be your best choice. If you had OEM suspension I would say powerflex.