[Irish335i]

I purchased a 2011 CPO 335i M-Sport about 2k miles ago. Between the winter weather (the RFTs are summer tires) here on the east coast and the city road conditions of Baltimore, I have to make a change.

I had test driven an M-sport xi locally, and learned afterwards about the suspension difference from this forum. Unfortunately, the supply of 2011 white M-sport with the minimum packages I wanted was scarce, and after finding a near-perfect RWD 335i, I was torn (plus the end of my G37x lease was approaching quickly). After doing some research and hearing opinions that the sport suspension wasn't "that much" harsher than the xi, I decided to just go ahead and get the non-xi.

On smooth highways, the car is an absolute dream. Having had both the G and the 335 simultaneously for a few weeks, I would switch back and forth as I tried to hit the exact mileage on the G lease for turn in. I found myself dreading the days I had to drive the G, except for the first and last 5 minutes of my trip to work as I left the city and got off the freeways. I do love the road connection from the 335 90% of the time - but I realize now that I favor ride quality more than I thought I would.

My options:

1) Keep the 18's, switch the RFT to Conti DSW
2) Move to 17's, and Conti DSW (I do love the 193's though...)
3) Keep the 18's, switch to RFT, switch to Koni Yellow's or FSD (and switch springs? I don't know how much the stock M-sport springs are contributing to ride quality, but I could deal with gaining a tiny bit of wheel gap if it would make a big difference)
4) Switch to the 335 non-sport shocks/springs and try to sell my sport susp.

My next car will definitely take ride quality into account more, but for now, I love this car and want to enjoy it even more without entirely loosing the sport feel.

Thanks in advance for all the advice and opinions!

[jjellyneck]

Depending on your budget, there are options for both a better ride and better handling. It would involved non runflat tires (as you are planning to do), and dampers.

Suggestions for dampers with your existing springs:
Koni FSD
Bilstein

Many of the coilovers also do an excellent job of both, but $ more...in the range of $1000-2400. This includes KW (V1 and Street Comfort) and Ohlins. Others can do a great job as well.

[gtaccord]

Runflats will make a big difference. Go with runflats on the 18s.

[cvc 22349a]

Originally Posted by jjellyneck

Depending on your budget, there are options for both a better ride and better handling. It would involved non runflat tires (as you are planning to do), and dampers.

Suggestions for dampers with your existing springs:
Koni FSD
Bilstein

Many of the coilovers also do an excellent job of both, but $ more...in the range of $1000-2400. This includes KW (V1 and Street Comfort) and Ohlins. Others can do a great job as well.

I had Koni FSD for a couple years and have to say they're a junk damper; they're inconsistent and underdamped on sharp impacts. Koni Sport is a good damper and provides good handling and ride quality with oem springs.

Irish: Getting rid of the runflat tires improves ride quality and grip more than anything. Koni Sports or Bilstein HD with your oem springs will further that improvement. Those Contis have soft sidewalls so the turn in response will slow down. There's a trade off for everything.

[jjellyneck]

Yes that seems to be the consensus about the FSD for aggressive driving or very hard bumps or big road undulations. Not always a consistent feel or performance.

[Irish335i]

Thanks so much for all the responses and recommendations.

I'm going to swap out the RFT's and then evaluate the ride quality to see if more is needed.

As far as the Koni Sports (is this synonymous with Koni Yellow?), how would they compare to the stock non-sport suspension?

[ashmostro]

Start with ditching those RFT's. I guarantee you will feel a huge difference in bump compliance. The RFTs are that horrible.

18"s are a great size for performance, comfort, and looks on these cars.

I doubt you will need/want Koni Yellows after making the change, given your comments.

Switching to non-sport shocks and springs won't do much other than make the car wallow more and ride higher. Don't bother with that.

[E92mech]

I have an E92 M-sport here in Baltimore as well and I have 3 sets of wheels: OEM 19" type 225 M wheels with 225/255 Michelin PSS, 18" Forgestar F14 8.5F/10R with 235/265 Michelin PSS, and for winter 18" Enkei Raijin 8.5F/9.5R with 235/265 Dunlop Sport 3D. When I bought the car and replaced the original run-flats on the 19" wheels with the PSS that made a huge difference. Then I went to 18" and that made an even bigger difference, although I think part of that is due to the fact that when I went to 18" I also dropped 40lbs of unsprung weight. At the very least just ditching the run flats will help you a lot. I personally really like running the 18's for performance reasons, and I actually think they look more purposefully badass than the 19's, but that's subjective.

Send me a PM as we're local to each other. You are welcome to experience the ride difference yourself.

[tunachris]

I put KW Series 1 coil-overs on my 2010 E92. I also replaced the RFT with Michelin PSS 2's. Even though the car sits quite a bit lower now, the ride is better than it was with the RFT. Body roll is minimal, and the combination of the suspension and tires has improved the handeling markedly. I later installed a Quaife LSD, and I plan on changing out the control arms, and other pieces with M3 parts. At this point the car handles much better than stock, and I anticipate it will go up another notch or two with the M3 bits.

[Eat.Sleep.Race]

i vote for buying a cadillac for work car. lol