M3 + xDrive?

[Kevlar]

Another crazy idea... by yours truely.

Now here me out, we've all debated over the fact how we prefer RWD vehicles... but we can't deny the fact that AWD does have it's bonuses in certain circumstances.

Enter xDrive...

xDrive is a fully electronic AWD system with the ability to transfer torque from front-to-rear or rear-to-front a full 100% in just over 100 milliseconds.

Now my theory...

Why not put xDrive on a M3? Yes, we love RWD, but how about a button to disable (or enable) it? Under the 90% of our driving, we could have the system set to RWD, but when we need it, we can enable the system to do it's job.

Or even better...

Why not make a few options. By default it's a 10% front, 90% rear split, but with a knob in the passenger cabin, we can vary the split from 0% 100% to 50% 50% depending on how we feel on any given day (or we could just leave it to auto for the people who don't care).

Yes... there would be some added weight, but I'm sure BMW could find a way to compensate for the weight with some new composite materials.

And because it's a fully electronic system, you wouldn't have the added drag of a full-time AWD vehicle. Plus, think about the benefits. You could launch with a 25/75 split then after the first 60feet... switch to 100% RWD.

Crazy, yes... I know, but it's an idea I had.

[daihard]

An interesting idea. The Skyline GT-R has always had the system that transfers the power between the front and rear wheels (called ATTESA 4WD). Given its success on the streets and the racetracks, I'd say adding a system like that to the M3 will potentially boost its already stunning performance.

If they do that, though, I hope they put the car on a diet. 3,400 pounds is already pretty heavy. Adding a 4WD system will not help in that respect.

[///MDriver]

Wouldn't that go against BMW's ///M car philosophy? Its an interesting idea, but I doubt we will ever see it.

[themadhatter]

I'd buy one and it would have to have a method for the driver to directly interact with the distribution like the Skyline has.

Weight would be another concern, how much does the 330xi weigh over the 330i?

I'd really like to see a stripped down version of the M3 - no HK, light weight seats, extensive use of aluminum and carbon fiber etc.

now that would be fun

-Ron

[///MDriver]

There's no doubt that the 330xi offers superior performance on ice, snow and gravel when compared to the rear-wheel-drive 330i, but there are some penalties related to the extra weight. The all-wheel-drive model is 95 kg (209 lb.) heavier than the rear-drive model, which means a slight penalty in fuel consumption.

http://www.canadiandriver.com/testdrives/01bmw330xi.htm

[themadhatter]

if the system were directly transferable with no increase in weight then the 209lbs penaly would be livable.

heck some people's trunk funk weigh well over 200lbs with all that mdf, wiring, amps and subs.

-Ron

[///MDriver]

No where in BMW's sale pitch do they mention the phrase "x-Drive" in relation to the 3 series awd. They call it all wheel drive assisted by "DSC-x". Also, "on dry roads, a 38%-front 62%-rear torque split".

So it looks like its not 100% adjustable, nor is it even x-drive.

The X3, on the other hand, calls its awd system xDrive. Maybe just a technicality, but I think that the xDrive with its more complex workings is probably heavier than the awd system offered on the three series.

[Kevlar]

Originally posted by ///MDriver
No where in BMW's sale pitch do they mention the phrase "x-Drive" in relation to the 3 series awd. They call it all wheel drive assisted by "DSC-x". Also, "on dry roads, a 38%-front 62%-rear torque split".

So it looks like its not 100% adjustable, nor is it even x-drive.

The X3, on the other hand, calls its awd system xDrive. Maybe just a technicality, but I think that the xDrive with its more complex workings is probably heavier than the awd system offered on the three series.

Yes, BMWs previous generation AWD system was a locked 38/62 split. The new xDrive system is full electronically variable 0/100 or 100/0 or anywhere inbetween within 100 milliseconds. Unfortauntely, the system is electronically controlly by the DSC system and takes no interaction from the driver (no control in the cabin). However, the system switchs to full 100% RWD as speeds over 100mph and below that it varies depending on feedback from the DSC system.

For instance, when understeer is detected, power is transferred 100% to the rear and with oversteer, power is increased to the front, but not totally cut from the rear as to not trigger a rebound drift affect. When starting on ice... power is shifted 100% front.

[NegativeCambre]

Adding an AWD without adding a significant amount of weight (200lbs is a LOT!!!) is kind of a hoop dream. I agree with hatter on this one, a stripped down version of the M3 (maybe a "track edition" or somethign to that extent) that doesn't cost a bazillion dollars like the CSL and can be had in America would be SWEET.

Steve

[///MDriver]

Originally posted by Kevlar
Yes, BMWs previous generation AWD system was a locked 38/62 split. The new xDrive system is full electronically variable 0/100 or 100/0 or anywhere inbetween within 100 milliseconds.

For the time being though, this is only available on the SUVs. The cars haven't adopted this system yet, if at all.

[12:03]

tis blasphemy....

:

[themadhatter]

blasphemy? never! it'll be called the M4.

[daihard]

Originally posted by StevenRyan
Adding an AWD without adding a significant amount of weight (200lbs is a LOT!!!) is kind of a hoop dream. I agree with hatter on this one, a stripped down version of the M3 (maybe a "track edition" or somethign to that extent) that doesn't cost a bazillion dollars like the CSL and can be had in America would be SWEET.

I hope for the same, but doubt we're ever going to see it in the U.S. I'm sure BMW has done marketing researches and concluded that the number of potential buyers for a lightweight version of M3 will not be enough to justify bringing one in.

[daihard]

Originally posted by ///MDriver
For the time being though, this is only available on the SUVs. The cars haven't adopted this system yet, if at all.

I wish the 325xi had xDrive. My wife is looking for a 4WD car/SUV now. We're considering an X3 2.5 or a 325xi Sports Wagon. If the latter was equipped with xDrive, it would be a lot easier to make the final decision.

[themadhatter]

this is where the lotus elise will come in and take over - it's a virtual E30 M3 in terms of what it's meant to be.

light weight purpose built sports car with little frills and no heated seats.

-Ron

[dhruvp]

I just watch the Top Gear episode where Tiff takes the Skyline GT-R for a spin and all I can say is wow! If BMW could get an AWD system in the M3 it would make it sick, especially if that power could be transfered... However, with the recent trend of cars getting heavier and heavier I don't think it's a viable option for a car like the M3. The added weight does not outweigh the benefits in my opinion. It would have to be a CSL type car with that sort of modification. And in the slightest chance that something like that became reality, I highly doubt that BMW would sell it here ala CSL

[JLee]

that would be awesome, maybe PTG or one of the bmws could finally beat Audi off the line in speedworld challenge...

I think quattro's proven launching abilities would make the Ultimate driving machine even better, so the question is why wouldn't they do it.

jeff

[nsk223]

A common misconception on car forums is that awd is better than rwd because 4>2. Part of what makes the m3 the wondefully balanced and fun car that it is, is the fact that it's rwd. Quite simply, rwd cars are better driver's cars; they respond much more directly to throttle inputs and they make more efficient use of the tires. The above post says that 'it would be great if ptg used awd because they would be faster off the line." While the cars would be faster off the line, they would have that same issues with weight and tire wear that the audis have. The point is that while awd has its advantages, it is not a better system per se. Sure, Tiff put on a good show in the Skyline GTR, he also put on a good show in the fwd Ford Puma (Top Gear car of the year 97 or 98) and he also put on a great show in the E46. It's tempting to go along with the idea of an awd M3 that weighs the same as a rwd M3, and there are certainly driving styles and geographic locations which would support such a car, HOWEVER, even if this hypothetical car weighed the same, it would not therefore be a better car. The dynamics of a rwd car are, in the majority of professional driver's eyes, preferable to awd. If you want awd, get an S4. If you can't appreciate the dynamics of rwd, learn how to drive it (i.e driving schools and car control clinics. I promise you that, with enough track time, pretty much all of you would prefer that future M3s be rwd.

[daihard]

I don't disagree with you about the pros and cons of the RWD and 4WD cars. One thing I want to ask you though is, what is your definition of a "better" car? I do feel that RWD is more fun to drive than 4WD, and if that means RWD is better, hey, I'm a happy camper. But is RWD necessarily faster than 4WD? Lancia was dominating WRC with its RWD cars until Audi introduced the Quattro...

[Kevlar]

But what you guys are not getting here is the system would have the ability to be turned off. So in essence, most of the time the car would be RWD, giving you the bonus of RWD driving. The only time you would want the AWD system would be in incliment weather or if you wanted a aggressive launch or if the surface was less than optimal... like rain.

Remember, it's fully electronic and can be bypassed.

But this is all just a theory. I don't like AWD cars for driving or track purposes personally, but you can't deny the fact that an AWD system would have a bonus here or there... especially if you could turn it on/off.

[daihard]

Originally posted by Kevlar
But what you guys are not getting here is the system would have the ability to be turned off. So in essence, most of the time the car would be RWD, giving you the bonus of RWD driving. The only time you would want the AWD system would be in incliment weather or if you wanted a aggressive launch or if the surface was less than optimal... like rain.

Are you thinking about a system that you can manually turn on/off and/or change the torque transfer rate between front and rear, or one like Skyline's ATTESA where it's controlled entirely by the computer? Just curious.

[Kevlar]

Originally posted by daihard
Are you thinking about a system that you can manually turn on/off and/or change the torque transfer rate between front and rear, or one like Skyline's ATTESA where it's controlled entirely by the computer? Just curious.

Since it's electronic, you could have both. You could have a knob in the passenger compartment. You of course would have an AUTO setting for those people who just don't care... then of the enthusiasts, you could have a setting which would do...

100 front / 0 rear (FWD, equivalent to a Honda or something)
80 front / 20 rear
60 front / 40 rear
50 front / 50 rear
40 front / 60 rear (equivalent to the previous generation AWD)
20 front / 80 rear
0 front / 100 rear (which would be pure RWD just like an M3 is now)

or any variation of the above. It's electronic, so you should in theory beable to adjust it down to 1% increments.

[nsk223]

Bobo, YES. The weight of a the necesary parts to allow such an idea would weigh a TON. Secondly, if BMW could lose the necesary weight from the M3 to maintain its current weight while adding an awd system, wouldn't you just rather BMW take that weight off the car and NOT get awd: in other words make the current car a lot lighter.

Umm, yea Quattro represented a significant advantage for audi when it was first introduced because WRC races on gravel. With lower levels of grip, awd cars are generally better at putting the power down. Let's not forget Auberlen's performance in the rwd PTG car in the pouring rain at Lime Rock in 02-he lapped the awd cars.

[daihard]

Originally posted by bobo5
And as for the AWD, if it is going to be offered, it will be during the next evolution of the M3, I just don't see BMW reengineering the current body style to accomidate such a major design change. little things here and their are changed... for instance OBD1 to OBD2 in the E36's that was a major change, but a government enforced one, ASC added to E36's, a small change.... but AWD to the current body, don't see it happening, just wait 'til the new M3 is released, MAYBE such a beast will have the option.

Well E46 is offered with 4WD as 325/330xi. Since M3 shares the chassis with the non-M 3-series, I'd imagine the platform per se is ready for the change.

[teknopanda]

An M3 with x-drive is something I'd be all for. And it'd finally put to rest the already ridiculous comparisons of the M3 with EVO's and STI's