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View Full Version : What does differ BMW from other brands ?


AM123
03-06-2011, 09:57 AM
1) One man told me once that my X5 has an adaptive transmission. It means that the car remembers how fast u drove it and adopts itself to your habits.

The question - don't other brands have the same property and can u describe this property more accurate?

2) Another my friend advised me that an extraordinary feeling appearing during driving a BMW car is due to the fact that the weight balance in a BMW has been accomplished for 100%, tires are in the closest distance to the ends of a car, an engine is in the closest distance to the center of gravity.

Which other majour properties of BMW cars do u know ? I mean those which distinguish BMW cars from other cars ?

Yorgi
03-06-2011, 10:48 AM
1) BMW has been using adaptive transmissions for over 15 years. I am sure almost all car manufactures use the same technology these days.

The transmission learns your driving style and then changes the gear shifting pattern to match how you drive. If you are aggressive it will rev higher and shift closer to redline, if you drive at a slower pace it will shift early.

These days adaptive transmissions are very advanced and will shift differently in the winter vs summer and they recognize when you are in rush hour traffic or on the twisties etc...

2) BMW aims for a 50/50 weight distribution on all of their cars. Cars handle their best when there is equal weight distribution over the front and rear axles. When you turn the car weight shifts around from wheel to wheel and when the car has 50/50 weight distribution the shifting weight will be linear and predictable which is one of the requirements for a good handling car. It also makes a huge difference when driving the car at the limit.

It takes a lot of work to achieve 50/50 weight distribution. BMW mounts engines low and close to the firewall, they put the battery in the trunk, they use lightweight materials on the front of the car, etc...

swajames
03-06-2011, 01:20 PM
2) BMW aims for a 50/50 weight distribution on all of their cars. Cars handle their best when there is equal weight distribution over the front and rear axles. When you turn the car weight shifts around from wheel to wheel and when the car has 50/50 weight distribution the shifting weight will be linear and predictable which is one of the requirements for a good handling car. It also makes a huge difference when driving the car at the limit.

It takes a lot of work to achieve 50/50 weight distribution. BMW mounts engines low and close to the firewall, they put the battery in the trunk, they use lightweight materials on the front of the car, etc...

The problem, of course, is that the 50/50 and supposedly ideal weight distribution is only that way when the car is stationary. When driving, and particularly at the limit, it's not quite so clear cut. The load will transfer based on what the car is doing.

Load transfer to the rear provides under acceleration provides much better traction for the driven wheels and load transfer to the front means the weight balance gets closer to neutral under heavy braking. If you look at most modern Ferraris, Lamborghinis, Lotus (and of course Porsche) you'll find the weight distribution tends to be closer to 40/60. The 50/50 car becomes nose heavy under braking where a rear biased car will under load transfer tend towards neutral. There's also the question of steering feel - it's no surprise that the steering feel in the many of the higher end cars is better, in large part because of the generally reduced load over the front wheels.

I am not, of course, saying 50/50 weight distribution is bad, but the bigger picture is nowhere near as clear cut as your post implies. There's a lot of complex interaction with load transfer, your car's center of gravity, your car's polar moment of inertia and a host of other things that impact feel, handling and balance.

Yorgi
03-06-2011, 01:40 PM
The problem, of course, is that the 50/50 and supposedly ideal weight distribution is only that way when the car is stationary. When driving, and particularly at the limit, it's not quite so clear cut. The load will transfer based on what the car is doing.

Load transfer to the rear provides under acceleration provides much better traction for the driven wheels and load transfer to the front means the weight balance gets closer to neutral under heavy braking. If you look at most modern Ferraris, Lamborghinis, Lotus (and of course Porsche) you'll find the weight distribution tends to be closer to 40/60. The 50/50 car becomes nose heavy under braking where a rear biased car will under load transfer tend towards neutral. There's also the question of steering feel - it's no surprise that the steering feel in the many of the higher end cars is better, in large part because of the generally reduced load over the front wheels.

I am not, of course, saying 50/50 weight distribution is bad, but the bigger picture is nowhere near as clear cut as your post implies. There's a lot of complex interaction with load transfer, your car's center of gravity, your car's polar moment of inertia and a host of other things that impact feel, handling and balance.I'm an old track dog and I am fully aware of the 911's advantages of rear weight bias when it comes to braking and accelerating out of slow corners but the bias also requires a very skilled driver to prevent what the car naturally wants to do in fast or off-camber corners and especially in the wet - spin and go backwards off the road. No problem for race drivers and track day regulars but deadly for drivers with more money than skill. Same goes for the mid-engine exotics. BMW and Porsche have two different philosophies and you could argue until the cows come home as to which one is better.

That said my next track car will probably be a GT3 RS. :)

AM123
03-06-2011, 02:28 PM
Thanks to both, but do u know some other special properties of BMW ?

Yorgi
03-06-2011, 11:38 PM
Thanks to both, but do u know some other special properties of BMW ?What exactly are you looking for? Things to tell your buddies that BMW's have and that their cars do not? Or are you just interested in some features your car might have that you don't know about?

02BMW530
03-07-2011, 05:22 AM
I had a 1993 VW Golf 1.8 with a 4 speed adaptive automatic. While maybe not as sophisticated as our BMWs, it would switch between Economy and Sport (Ha!) mode depending on how you drove.

BMWs have lots of cool things like double pull door handles that will bog down your friend's exit from the car (great for after a Taco Bell lunch and you rip one while he has to try to figure it out) and expensive maintenance.



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335i Driver
03-07-2011, 07:24 AM
I had a 1993 VW Golf 1.8 with a 4 speed adaptive automatic. While maybe not as sophisticated as our BMWs, it would switch between Economy and Sport (Ha!) mode depending on how you drove.

BMWs have lots of cool things like double pull door handles that will bog down your friend's exit from the car (great for after a Taco Bell lunch and you rip one while he has to try to figure it out) and expensive maintenance.



Sent from my iPhone using BimmerApp

Actually I think that's better for a car that doesn't have DS mode. I've never liked an adaptive transmission with no other driver options. You putt along in traffic all the time and it learns that as your driving style and then when you finally get some free roads and want to open it up you get nothing.

There's a big difference between my driving style due to the conditions vs what I would like for my driving style to be and actually is when I finally get an open road.

Oh, and a couple more thing about BMW's - they have 2 kidneys on the front grill and a propeler on the front center of the hood.

AM123
03-07-2011, 01:29 PM
What exactly are you looking for? Things to tell your buddies that BMW's have and that their cars do not? Or are you just interested in some features your car might have that you don't know about?

Both.

First to tell buddies and to me what my car has their cars do not and as a consequence to be able to explain myself why just on BMW I feel myself very compfortable ( I owned Lexus LX for 5 years, I also own now Mercedes ML and X5 but feel on BMW what I don't feel on others - I want to understand why?).

And the second reason you indicated is also important. For example I didn't understand why at some moments it accelerates very fast but sometimes "thinks" as if there is a lag , after I got what is an adaptive transmission I understood why. But, of course, the speech is about some majour properties not about minor properties like "some combinations of buttons opens some display screen and etc.." that I may not know.