20" Wheels Driving Impressions
 

OK, I have a 2011 Xdrive 5.0 Sports Package Adaptive Drive. Came with Style 335 19" x 9" wheels - 255/50/19 tires. I got rid of the run flats immediately and went to Vredestein Wintrac snows. The Vreds were a huge improvement (overall) comparted to the Conti run flats.

fast forward to today

Installed Avante Garde M510 20" x 10" Wheels with Vredestein Ultrac SUV Sessantas.

The wheels weigh 30 lbs each and the BMW Style 335s weigh 36 lbs. The Sessantas are 1.5 (rear) - 2.5 lbs (fronts) lighter than the Wintracs so overall I reduced unsprung weight by 7.5 (rear) - 8.5 lbs (fronts) per wheel.

315/35/20 - rear
275/40/20 front

Driving impressions after taking a 40 minute drive out in some twisty Colorado canyons:

I was surprised. The car immediately felt more grounded -I don't mean cumbersome - I mean more stabile. The reduction in weight was also noticeable - the car felt very quick to respond and jump forward upon acceleration (Another time I reduced an E36 M3s weight by 10 lbs per wheel and that difference was larger) However, the 8 lbs per wheel has given the X (I believe) a slightly more nimble response. Although, I realize this will come at the same time as much wider tires which will have their own characteristics.

The cornering was improved, being extremely flat and solid - more go kart like compared to the 19s. The turn in with the Sessanta summer tires was much quicker as well (to be expected).

Overall the feeling is that the X has become a bit of a sporty brawler, and I like it so far!

Another feeling that makes no sense - the car feels lower to the ground (in a good way). I haven't a very good idea why I would feel this, but it is a distinct impression and if I didn't know better, I would be wanting to conclude that the car was a couple inches shorter. The only thing I can surmise is that the "well grounded-ness given by the wider tires is producing in me the impression that I am driving a car that is lower to the ground.

Seriously, this X with Adaptive Drive is a pretty good cornering machine but the 20s with the sessanta tires has just increased the Xs cornering enjoyment by around 30% to 50% (again, all my subjective perception - nothing measured obviously). But, I am sure the car's real cornering ability has improved as well!

I can't wait to drive her some more tomorrow!

I need to go search some posts her by Ard on getting an alignment (and rhe specs to get dialed in) because I intend to have an alignment done in the am by a reputable shop!

More impressions to come, but I an happy so far and surprised by the increase in handling ability! :thumbup:

Here is a picture!

http://i1130.photobucket.com/albums/...psdf59fa12.jpg

More pictures here - scroll down to the Alpine White . . .

http://www.xoutpost.com/bmw-sav-foru...thread-38.html

Looks good! I went from OEM 19s to OEM 214s with Dunlop Sportmax run flats. The X5 looks worlds better with the fat tires.

You could use a wider fender flare though.

As far as alignment go, I'd go with minimal toe (1/16 toe in), and maybe -1 to -1.4 degree of camber in the back.

Extended Fender Flares are on the way!

I have the 336's and they are awesome. When I move to my winter 219's (255/19's) there is a bit of an adjustment. Not nearly as bad as when I bought 18's for my winters (quickly sold for 19"s) but i can feel the car with a bit more float but still feels very stable. I get the same from my M3 when I go from my 19's to the 18's, under hard acceleration i can feel the ass floating.

My wife always gets complements on the 315's on the rears all the time. I get a kick out of guys commenting on her tires. Makes the car look like a tank from behind. She always hates it when it starts getting cold because she knows I will be removing the massive 275's/315's for the puny 255's. She just asked me today when am I going to but her awesome wheels back on the car.

MRV99,

That's why I got a 20" winter wheel/tire combo. I couldn't stand the puny tires in the winter :)

So you have all seasons or 20" winters? I am sorry but I don't do all seasons and I know myself and my wife both agree that we would rather have weak looking winter setupa than (x5 and m3) than use allseasons. Yes many people say they are fine but here in Chicago, I want the better winter performance. Winters have saved my a$$ from many a crazy out of control mini van.

Looks good, as you know I run the vreds as well. Only fault is that they look narrower than the OE Michellin tires, even in the same size

Yes, I'm sure the Vreds must be a little narrower than other brands such as Mich, Conti, etc. The Avant Garde rims are 10" wide and the Vred 315/35/20s are the only 315s I know of that are factory spec'd to fit a 10" wide rim.

But, they are plenty wide for me! Especially compared to the Vred Wintrac snow tires which are 255/50/19's.

And, I LOVE the Vred Sessantas - I just drove the X today about 250 miles and it was a dream - I had a couple stretches of backroad where I hit about 110MPH and is was as solid as a rock!