[IN54NITY]

Originally Posted by TrackRat

Rule changes don't allow AWD in most cases to compete with RWD as it's now acknowledged that AWD is an unfair advantage, as Audi proved even after IMSA added a lot of weight on the Audis.

Thanks! Just goes to show I've been out of touch with professional car racing. But I'm about to change that, I'm going to try to follow BMW this year, even though they're out of F1.

Originally Posted by TrackRat

AWD/snow tires aren't a substitute for driving skills and good judgment. That's why you see a lot of SUV's with AWD in the ditch for no reason in snowy conditions. Snow tires and AWD provide increased traction not driving skills.

+1 Everbody's 'only' got "4 Wheel Braking", as I like to say.

BTW, I'm leaning towards TC Kline for my suspension upgrade.

[philsteroni]

Originally Posted by howiedds

Even with AWD and winter tires..its not completely bulletproof..ive slipped down a small hill on dunlop m3s. I wasnt even going fast...and my xi slip past the stop sign with ABS going off like a machine gun. Still got to be aware of icy condition (nasty slushy turned into ice that happens here in the NE)

Did you try your hill decent control? Works like a charm when I use it down an icy hill.

[BRAISKI]

Originally Posted by TrackRat

AWD/snow tires aren't a substitute for driving skills and good judgment. That's why you see a lot of SUV's with AWD in the ditch for no reason in snowy conditions. Snow tires and AWD provide increased traction not driving skills.

Well put!

Thats the problem just because the car is AWD/4WD and maybe with winter tires ppl think they are invincible.

[PeteB]

Hi Everybody,
I want to say many posts on this site and this thread have been very helpful to me. I live in Denver but really want a 335i for its affordability, etc. So far I only find xi's for test drives at dealers, but we don't have any snow on the ground to test anyway!
Talk about a passionate debate for some -whoa. Overall, I have read many positive reviews of rear drive with the highest-tech winter tires available. Also, people not surprisingly love the abilities of x-drive in weather conditions.
I'm driving a '93 corolla. Its front drive, seasonal tires, and low mass have served me well over the last 6 winters, including many snowboarding trips.
I'm looking forward to a car, 335i, that is a phenomenal upgrade in every department -I've never owned winter tires except some studded sets. If I could afford it, the xi would of course provide even better winter traction, but again I'm already looking forward to a substantial improvement.
My dad owns a German auto shop and I expected, despite everything I've read, for a heavier 335xi (than my Corolla) to feel softer, or more disconnected like older MBs, like 300E or SL500 from early 90's. Not so - on dry pavement the 328 xi and 335 xi that I both drove felt like go-carts. Sharper and more nimble than my roll happy Co rolla!
I'm psyched at this point -thanks for all the good info everyone. -PeteB

[mashimarho]

BAH. too many mixed opinions. I want the 335.. If i HAVE to I might get the 328... It's either: 328xi... or 335i....
I'm just afraid I'll end up getting the 335i and wintertires then driving it in 2 feet of snow and regreting it.

Plus I do... like mods.

damn...


EDIT: maybe I'll add weight to the trunk in the winter + snowtires?

[howiedds]

Originally Posted by philsteroni

Did you try your hill decent control? Works like a charm when I use it down an icy hill.

it was just regular city driving. i didn't even think that the ground was that icy and i was going about 10mph, slowly stepped on the brakes...and abs when off like crazy...and the car kept sliding...shitiest feeling having your ( at the time) 3 month old car slide almost into crossing traffic. my friends in their suvs did the same thing..and we all have dedicated snows on. I was just saying that we aren't as invincible as you think in awd..and HP snows....in that predicament, studded snows would have been perfect...lol

[PeteB]

Originally Posted by mashimarho

BAH. too many mixed opinions. I want the 335.. If i HAVE to I might get the 328... It's either: 328xi... or 335i....
I'm just afraid I'll end up getting the 335i and wintertires then driving it in 2 feet of snow and regreting it.

Plus I do... like mods.

damn...


EDIT: maybe I'll add weight to the trunk in the winter + snowtires?

From what I understand, you will do fine with winter tires -there are many cars out there that weigh more or handle worse, and the owners often don't get winter tires (they ought to).

An article in one of the popular car magazines said they loved their M3 as a daily driver, even during winter. They said the winter tires made the car track well through snow. I guess growing up in Colorado I expect to slide in snow and plan to drive like a slow defensive grandpa in the winter. -Pete

[PeteB]

I sure have read a lot of debate for 335i vs. 335xi regarding the higher xi acceleration due to its increased traction.
I know some of the most common articles you can find online point out their experience of clocking higher 0-60 in the xi, but by 100 the weight difference prevails and the i is indeed ahead by enough fractions of a second to put the xi in its rearview mirror.
Now I don't know how often I'll be hitting 100 (well, highway) or actually perceive this difference. Of course the ~250lbs. shows up slightly in mileage, but obviously the same engine will be quicker with a lighter load.
The traction difference isn't enough overcome this by 100 mph.
But who even cares? I obsess over this stuff and if you get either the i or xi you're getting phenomenal performance, the differences are splitting hairs.
I'm sure xi is much more forgiving in snow but hey, it's more than just a 2000 dollar difference. I reviewed around 300 CPOs online recently- you can get a 335i under 30k miles for under $30k. To get this mileage with an xi, the price starts at $35K - big difference.
Finally, I'm just about to order a 2007 335i:
Sport, Premium, Cold, Comfort Access, Rear Park, Sunshades, and Active Steering.
I've seen a few of these loaded manufacturer's vehicles online and they seem to be great deals. -PeteB.

[PeteB]

Originally Posted by TrackRat

PeteB - the comments on acceleration are in regards to slippery surfaces, i.e. rain and snow. That's where AWD shows it's value for typical consumers. It's not in 0-100 drag races. On the track AWD is also superior in wet or dry but some folks prefer RWD for personal reasons. There is always a weight penalty with AWD but in return you get better traction. It just depends on your personal priorities but there is no escaping the reality that AWD provides better traction on any surface and that translates into more safety and for many drivers more fun.

I say buy what makes you happy as long as you're a technically informed consumer.

That is true - I do agree with all your comments. I realize I sort of left that aspect out of my post- I promise I'm not trying to advocate either setup. I think they're all really awesome cars and all wheel capability is a bonus on top of that. Thanks, Pete

[Hitzugaya]

Love me Xi with Kw v3s =)

[jpsimon]

i'd say it's an advantage Launching in an XI will break your neck if you aren't prepared

[jeveryday]

if your worried abt the snow, get the XI... The XI worked great for me.

[Nikolas]

LOL at the people adding weight to the trunk of a 3500 lbs car w/ 50/50 weight distribution!

It's not a pick-up truck. Adding weight will do nothing for your traction and ruin the dynamics of the car in any conditions.

[Nikolas]

Originally Posted by TrackRat

With all due respect increased weight = increased traction on any surface. One can argue having passengers in the rear seats alters the vehicle dynamics, driving with a full tank of fuel alters the dynamics, carrying your lunch, a spare tire or golf clubs in the boot alters the dynamics... The increased traction in a pick-up truck may be more dramatic, but the fact is more weight = more traction and in snow that's a good thing, especially in a RWD vehicle.

Sorry, but there is a point where weight does not equal more traction given the same contact patch of the tire. If you do not increase the contact patch, weight will eventually overcome the traction abilities of the tire. This is why lighter cars with awd fair much better than heavy cars like SUV's with awd. My point about adding sand bags in the trunk of a RWD car that already has 50/50 weight distribution is that it will make no difference, unless you are talking more than 300 lbs. At that point the dynamics that I refer to would be snap oversteer on the snow - no fun.

[kcboost335xi]

i had 6 speed 325i this last winter it did all right u just really got to watch wear your going , i traded it in for a 335xi but i drive 80 miles a day for work and we got a lot of heavy snow in kansas last year im not going through that again like they said if you dont have to go up a lot of hills rwd is all right

[Nikolas]

Originally Posted by TrackRat

Tires have a traction efficiency curve which shows the traction vs. vehicle weight on the tire, aka load. As you increase load on the tires the efficiency goes down but the traction still increases unless you get absurd and overload the tire beyond it's designed load capacity. In other words you don't get as much traction increase as the load increase but you still get more traction.

If you can't place a few hundred pounds of weight in the trunk then you can't carry passengers in the rear seats safely either without making the vehicle dynamics terrible - according to your beliefs. I'm not saying you can add 5,000 lbs. to the trunk, but adding a reasonable amount of weight does in fact increase traction and with a tire efficiency curve for a tire and the vehicle weight you could determine exactly how much is acceptable.

I can assure you from personal experience and physics that adding a reasonable amount of weight to the trunk will both improve traction and not cause snap-oversteer. In fact it actually improves rear tire traction.

Feel free to read any chassis engineering book on vehicle dynamics such as Herb Adam's "Chassis Engineering", Fred Pruhn's "Making your car handle", any of Carrol Smith's Engineering/Tuning/Suspension books, Allan Staniforth's "Competition car Suspension design, construction and tuning" or countless others for factual info. on the physics involved and how downforce, i.e vertical load on the tire most definitely increases traction unless you overload the tire beyond it's intended operating range, which a few hundred lbs. would never do.

So you honestly believe a heavier car given the same contact patch as a lighter car will do better in winter driving?

Well I guess I live in a little microcosm where the laws of physics do not exist. It is a small area that gets around 400 inches of snow annually and I can tell you that our lighter cars are far superior to the heavy ones. The traction ability of tires is easily over come due to excessive weight on the contact patch when you consider the surface of ice and snow. The problem with weight on a low friction surface is that it is much more difficult to control than that of a lighter vehicle. It's that little aspect of traction called gravity that takes over all advantages that the pressure on the contact patch provides.

[issabmw]

even in FL, the xi is a blessing, because of our notorious summer storms. in any situation where weather is not on your side, xi buffers the negativity.

[issabmw]

Originally Posted by TrackRat

In my experience there is no substitute for AWD, especially in snow and I've driven many makes and models of AWD, FWD and RWD models on dry pavement, in snow, on ice, in rain and on the race track. To each his own, but reality is reality.

+1 although I sometimes exhibit tads of awd understeer on occasions, the distribution throughout all four wheels gives the car a solid stance.

Then again, I like oversteering purposefully, thats what the 30ci is for

[Drakos]

Aside from lots of snow where I live, there is no substitution for being able to stomp and go without worrying about wheelspin.

[ImUsinIt]

I spend time in New Brunswick and Nova Scotia in Canada.
I used to drive a 323i and even with great snow tires, it came nowehere close to comparing to my 330xi's performance in the snow (with all seasons, at that).

On slushy days the difference seems to be not as great, however the xi still prevails.

Now do I miss the handling of RWD?

Yes...

But not as much as I hate digging my car out of a snowbank at 2:00 a.m.

It all boils down to where you live.
Out here we can have snow on the ground for 4 months so it was a no brainer for me to get the xi.

[Mimio]

Love it. My XI tracks and recovers better than my old A4.

[Nikolas]

Originally Posted by TrackRat

Feel free to compare a tire graph for traction vs. load, i.e. tire efficiency. Perhaps then you'll understand that adding weight, i.e. load to a tire will increase traction within the design limits of the tire. Any of the listed references in the post above have tire traction vs. load graphs to illustrate this fact.

You are joking I assume? Added weight may certainly help at initial start for a tire to gain traction, but I don't care what any graph shows. Added weight in slippery conditions does not help any vehicles ability to handle. If you have graphs that show otherwise great! I'll take my experience in living in an area for the last 16 years that gets over 400 inches of snow annually, over any graph you provide. Heavier vehicles do not handle as well as lighter vehicles on snow and ice. Given identical contact patches, the results are amplified. I see it every day all winter long.