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E90/E91/E92/E93 (2006 - 2013)
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  #1  
Old 07-01-2012, 08:39 PM
TXFred TXFred is offline
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Aggressive driving with a tiptronic.

Some smartass is going to post, "Get a stick shift."

The fact is, I prefer manuals. But a few years back I messed up my knee, and can no longer operate a clutch without pain.

I'm trying to find the best way to drive the Tiptronic in "manual" mode, especially when it comes to corners. I have a method, but I suspect that there are better methods out there.

It is my opinion that BMW's paddle shift system stinks. It's all well and good when you're going straight, but when you're shifting and cornering, you cannot find the paddles. Making the paddles move with the steering wheel was a dumb idea.

I have had better luck shifting with the selector.

Currently, I set the transmission to manual mode for this sort of work. Approaching the corner, I brake hard (ABS engaged), release the brakes and enter the corner. As I slow, the Tiptronic will downshift the car to keep the RPM's above 1000. I then downshift once manually. The manual downshift gets the car into a gear where it has some power. At the same time, I get back on the gas to exit the corner.

I'm no race driver, and I'm sure my technique can be improved. So I'd like to hear how others handle corners with the Tiptronic.

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Old 07-01-2012, 09:34 PM
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pointandgo pointandgo is offline
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Quote:
Originally Posted by TXFred View Post
Some smartass is going to post, "Get a stick shift."

The fact is, I prefer manuals. But a few years back I messed up my knee, and can no longer operate a clutch without pain.

I'm trying to find the best way to drive the Tiptronic in "manual" mode, especially when it comes to corners. I have a method, but I suspect that there are better methods out there.

It is my opinion that BMW's paddle shift system stinks. It's all well and good when you're going straight, but when you're shifting and cornering, you cannot find the paddles. Making the paddles move with the steering wheel was a dumb idea.

I have had better luck shifting with the selector.

Currently, I set the transmission to manual mode for this sort of work. Approaching the corner, I brake hard (ABS engaged), release the brakes and enter the corner. As I slow, the Tiptronic will downshift the car to keep the RPM's above 1000. I then downshift once manually. The manual downshift gets the car into a gear where it has some power. At the same time, I get back on the gas to exit the corner.

I'm no race driver, and I'm sure my technique can be improved. So I'd like to hear how others handle corners with the Tiptronic.

Frederic
I suspect that "smart asses" are lurking.
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  #3  
Old 07-02-2012, 02:04 AM
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Zooks527 Zooks527 is offline
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I'm not sure why you would do it this way. As described above, you're in manual mode, slow into the corner until the engine loads enough to auto-downshift because it's at minimum revs, and then you downshift again once. Seems like a way to guarantee you're out the bottom of the torque curve and lugging every time. That doesn't seem better than (and, in fact, looks like a degradation from) leaving it in Sport mode and letting the computer pick the best shift points. Sport mode may not give you the same shift points as you would do with a manual, but it would seem to be an improvement over guaranteeing overly low revs on every curve, which surely doesn't fit the description of "aggressive driving".

If you must do it manually, why not just shift to maintain the RPM band you want during the curve they way you used to with a manual, instead of slowing the engine all the way down?

Side note: BMW calls it a Steptronic. VW calls it Tiptronic.
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Last edited by Zooks527; 07-02-2012 at 05:04 AM.
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Old 07-02-2012, 05:59 AM
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If you are holding the steering wheel correctly for "racing", your hands should be 9-3 (or 9.30-2.30 because of the wheel spokes). Your fingers should be right by the the shift levers. If you are feeding the wheel, and lose the levers, you are not doing it right if you want to drive quickly.

You should be braking in a straight line and shift into your "exit" gear when the speed drops to the level that will allow that gear to get into the bottom of your torque band. This should be in a straight line before entering the corner too. You shouldn't be trying to turn and change gear at the same time.

As for braking, don't use the brake pedal (well, any pedal for that matter) as an on/off switch. To maximise the grip of your tires and minimize unsettling the car, you should squeeze the brakes on and progressively release them. This stops the front springs unloading too quickly and unweighting the front suspension and losing front end grip by sort of bouncing. If 0 is no brakes, and 10 is locked up, your brake pressure should be 0 => 1 => 9 => 6 => 3 => 1 => 0 through the braking zone - note the slow off. The braking is a hard squeeze, not a stamp. Try it, the car will feel different. This lets the tires load up somewhat gradually and maximize the grip. You can practice this at stop lights - try and stop without the front giving a jerk when the car comes to a stop. That "jerk" is the springs unloading and bouncing back at the car. A good comment from an instructor was "let the car know what you want to do...start slow and then make the action, whether is is accelerating, braking or turning" This lets the car's suspension adjust to the weight movement and will give you more control than jerking it about. Jerking the car around makes it feel fast, but all it does is make it feel uncomfortable.
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Last edited by ///M-ratedE90; 07-02-2012 at 06:01 AM.
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Old 07-02-2012, 07:37 AM
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Quote:
Originally Posted by ///M-ratedE90 View Post
If you are holding the steering wheel correctly for "racing", your hands should be 9-3 (or 9.30-2.30 because of the wheel spokes). Your fingers should be right by the the shift levers. If you are feeding the wheel, and lose the levers, you are not doing it right if you want to drive quickly.

You should be braking in a straight line and shift into your "exit" gear when the speed drops to the level that will allow that gear to get into the bottom of your torque band. This should be in a straight line before entering the corner too. You shouldn't be trying to turn and change gear at the same time.

As for braking, don't use the brake pedal (well, any pedal for that matter) as an on/off switch. To maximise the grip of your tires and minimize unsettling the car, you should squeeze the brakes on and progressively release them. This stops the front springs unloading too quickly and unweighting the front suspension and losing front end grip by sort of bouncing. If 0 is no brakes, and 10 is locked up, your brake pressure should be 0 => 1 => 9 => 6 => 3 => 1 => 0 through the braking zone - note the slow off. The braking is a hard squeeze, not a stamp. Try it, the car will feel different. This lets the tires load up somewhat gradually and maximize the grip. You can practice this at stop lights - try and stop without the front giving a jerk when the car comes to a stop. That "jerk" is the springs unloading and bouncing back at the car. A good comment from an instructor was "let the car know what you want to do...start slow and then make the action, whether is is accelerating, braking or turning" This lets the car's suspension adjust to the weight movement and will give you more control than jerking it about. Jerking the car around makes it feel fast, but all it does is make it feel uncomfortable.
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  #6  
Old 07-02-2012, 07:44 AM
Pasa-d Pasa-d is offline
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Besides what M-Rated said, I don't ever let the car do the downshifting, I always work down through the gears as the car slows to get to the gear I want to be in for corner exit. I use a combination of paddles and stick shifting. On a corner approach when all or most of the braking is in a straight line, I downshift with the paddles, particularly if I'm next to a wall or armco and I want both hands on the wheel. On a corner with more trail braking or where there's open space next to the corner entrance, I will most often reach for the stick. There's no reason for that other than the paddles still feel weird to me.

People will say I shouldn't be shifting in the corner, but it's different in a automatic because you upset the car very little with a downshift due to the indirect torque connection and unfortunately you are sometimes forced to do this just because of the sequential shifting, the time delay between shifts and the ECU's control over the actual shift.

All these comments are in a track setting, so you have many opportunities at the same corner to get it right and fine tune your approach. I don't drive anywhere near this hard on the street for it to make any difference. Even when running the canyons I just leave it in sport mode and focus on being smooth.
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Old 07-02-2012, 08:12 AM
dtc100 dtc100 is offline
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I consider our E90 328i AT the last batch of fun cornering sedans for street driving. A good compromise for many who must share the car with manual-hating spouses or SOs.

While I totally agree with the above assessment for track and autox, it takes out a lot of fun in street conditions, because in street driving you rarely get to the point of letting the tires break loose under the speed limits, even if you take on a band or corner at 20 mph above, especially if you have a set of good summer tires. Not that I do it but this is just how I think your tire grip should be at a minimum.

The most fun is to first make sure it is safe, no traffic around, then quickly approach and just as you begin the turn, hit the brakes hard, and release it as you just about to come out of the corner but before the car straighten itself.

If you want to add some manual driving feel to it, use what they call "throttle blip" in the sport mode (works in standard mode also but I doubt you are in that mode at this point anyway). Before braking, quickly tap the throttle, if you do it right, the tranny will shift to a lower gear and hold it while you corner.

The throttle blip needs some practice to activate consistently. If it does not trigger it can be awkward. But if it works, can be a lot of fun. I am at the point I can make it work 80% of the time.

I don't use manual mode for this, it is too slow to react to your shift.

Keep in mind this is to assume your tires will chirp but are never loose in such action, and your traction control is not turned off.

Last edited by dtc100; 07-02-2012 at 08:29 AM.
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Old 07-02-2012, 11:03 AM
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Quote:
Originally Posted by dtc100 View Post
I consider our E90 328i AT the last batch of fun cornering sedans for street driving. A good compromise for many who must share the car with manual-hating spouses or SOs.

While I totally agree with the above assessment for track and autox, it takes out a lot of fun in street conditions, because in street driving you rarely get to the point of letting the tires break loose under the speed limits, even if you take on a band or corner at 20 mph above, especially if you have a set of good summer tires. Not that I do it but this is just how I think your tire grip should be at a minimum.

The most fun is to first make sure it is safe, no traffic around, then quickly approach and just as you begin the turn, hit the brakes hard, and release it as you just about to come out of the corner but before the car straighten itself.

If you want to add some manual driving feel to it, use what they call "throttle blip" in the sport mode (works in standard mode also but I doubt you are in that mode at this point anyway). Before braking, quickly tap the throttle, if you do it right, the tranny will shift to a lower gear and hold it while you corner.

The throttle blip needs some practice to activate consistently. If it does not trigger it can be awkward. But if it works, can be a lot of fun. I am at the point I can make it work 80% of the time.

I don't use manual mode for this, it is too slow to react to your shift.

Keep in mind this is to assume your tires will chirp but are never loose in such action, and your traction control is not turned off.


Oh my...not sure where to start with this...

Make sure that if you follow this advice that
a) it's dry
b) traction control is on, you'll need it to get around the corner
c) send a card to BMW driving dynamics engineers thanking them for their superb system which will be responsible for getting you home

Quote:
The most fun is to first make sure it is safe, no traffic around, then quickly approach and just as you begin the turn, hit the brakes hard, and release it as you just about to come out of the corner but before the car straighten itself.
This has to be the worst advice I have ever read on Bimmerfest...which has some strong competition...

[I'd like the GBP10 argument please]
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Old 07-02-2012, 01:27 PM
dtc100 dtc100 is offline
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Originally Posted by ///M-ratedE90 View Post


Oh my...not sure where to start with this...

Make sure that if you follow this advice that
a) it's dry
b) traction control is on, you'll need it to get around the corner
c) send a card to BMW driving dynamics engineers thanking them for their superb system which will be responsible for getting you home



This has to be the worst advice I have ever read on Bimmerfest...which has some strong competition...

[I'd like the GBP10 argument please]
I know I know, but we are talking 328i, or even 335i, and in street driving. With a good set of tires and balanced weight at the rear, the power delivered are unlikely to break your tires loose. Don't try this in an M3 or a muscle car.

I get the tires to chirp but never had triggered traction control. And I was talking about dry conditions of course.

Different environment, different way to have fun. You can of course use the correct techniques tailored to tracks, and be bored to death.

Last edited by dtc100; 07-02-2012 at 01:28 PM.
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Old 07-02-2012, 01:41 PM
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DSXMachina DSXMachina is offline
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Originally Posted by dtc100 View Post
I know I know, but we are talking 328i, or even 335i, and in street driving. With a good set of tires and balanced weight at the rear, the power delivered are unlikely to break your tires loose. Don't try this in an M3 or a muscle car.

I get the tires to chirp but never had triggered traction control. And I was talking about dry conditions of course.

Different environment, different way to have fun. You can of course use the correct techniques tailored to tracks, and be bored to death.
Dtc, I'm afraid that your way can lead to some exciting videos on YouTube, but M's way is the fast way.
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Old 07-02-2012, 01:57 PM
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cwinter cwinter is offline
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Quote:
Originally Posted by dtc100 View Post
I consider our E90 328i AT the last batch of fun cornering sedans for street driving. A good compromise for many who must share the car with manual-hating spouses or SOs.

While I totally agree with the above assessment for track and autox, it takes out a lot of fun in street conditions, because in street driving you rarely get to the point of letting the tires break loose under the speed limits, even if you take on a band or corner at 20 mph above, especially if you have a set of good summer tires. Not that I do it but this is just how I think your tire grip should be at a minimum.

The most fun is to first make sure it is safe, no traffic around, then quickly approach and just as you begin the turn, hit the brakes hard, and release it as you just about to come out of the corner but before the car straighten itself.

If you want to add some manual driving feel to it, use what they call "throttle blip" in the sport mode (works in standard mode also but I doubt you are in that mode at this point anyway). Before braking, quickly tap the throttle, if you do it right, the tranny will shift to a lower gear and hold it while you corner.

The throttle blip needs some practice to activate consistently. If it does not trigger it can be awkward. But if it works, can be a lot of fun. I am at the point I can make it work 80% of the time.

I don't use manual mode for this, it is too slow to react to your shift.

Keep in mind this is to assume your tires will chirp but are never loose in such action, and your traction control is not turned off.
You know, when I first got my car in 2009 and had only driven it for perhaps a week, I came upon a wreck on my way to work of another, brand new, E90 335i M-sport sedan. It was Jet Black too and the LCI was in its first few months of availability so the car stood out to me, as I was essentially driving its 328i non M-sport equivalent. The 335i still had dealer paper plates on it.

Somehow, on dry pavement and just after a very slight turn, on a 2-lane road, the drive had somehow managed to do a 180 and run the rear tires over the curb. Nobody was hurt, no other car was involved, but clearly the rear-suspension of the car was in some major pain. Perhaps the car wasn't totaled, but I doubt it ever drove the same.

In any case, I always wondered what in the world the guy did. Perhaps too much fun with DCT off on a car pushing 300 ft-lbs of torque on the rear; who knows. I almost stopped to add some condolences. However, I think you describe another possible scenario for what happened to that car.
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  #12  
Old 07-02-2012, 02:00 PM
dtc100 dtc100 is offline
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Dtc, I'm afraid that your way can lead to some exciting videos on YouTube, but M's way is the fast way.
My cornering described above was not to go fast, but to have fun. Next you probably will argue a burnout is stupid too.

I know when I was at autox it would not work, since there are too many more turns and straight lines ahead, you need to get there fast, and your tires are chirping all the time anyway, anymore excitement can overwhelm the senses.

But at your street corner, there is only one shot to get some excitement out of it before you must again stop alongside a Prius at the light. And the way those Prius drivers go aggressively in straight lines these days, without the regard of traffic, a corner with some drama might be the only way to show them what they are missing, and still be safe and responsive at it.

Last edited by dtc100; 07-02-2012 at 02:05 PM.
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Old 07-02-2012, 02:20 PM
dtc100 dtc100 is offline
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You know, when I first got my car in 2009 and had only driven it for perhaps a week, I came upon a wreck on my way to work of another, brand new, E90 335i M-sport sedan. It was Jet Black too and the LCI was in its first few months of availability so the car stood out to me, as I was essentially driving its 328i non M-sport equivalent. The 335i still had dealer paper plates on it.

Somehow, on dry pavement and just after a very slight turn, on a 2-lane road, the drive had somehow managed to do a 180 and run the rear tires over the curb. Nobody was hurt, no other car was involved, but clearly the rear-suspension of the car was in some major pain. Perhaps the car wasn't totaled, but I doubt it ever drove the same.

In any case, I always wondered what in the world the guy did. Perhaps too much fun with DCT off on a car pushing 300 ft-lbs of torque on the rear; who knows. I almost stopped to add some condolences. However, I think you describe another possible scenario for what happened to that car.
I actually did try the same cornering in two separate 335s, one standard, one with sport. Even the 335 did not manage to break the rear loose, though I was more cautious and did not let the nose dive too much. The wheel chirping effect is what I am after.

Just to be clear, I let off the brakes and am on the throttle hard before the car is fully out of the corner to avoid any spin. So far have not activated TC, and I don't turn TC off BTW.

No matter how aggressive you drive in the street, it does not compare to off road racing, not even close.

Last edited by dtc100; 07-02-2012 at 02:23 PM.
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Old 07-02-2012, 04:58 PM
dtc100 dtc100 is offline
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I think I do need to make it clear if you follow what I do, do so at your own risk, or listen to the pros.

But I want to ask the pros something. I am pretty sure what kind of car you drive makes a big difference as far as what technique is used.

I have read a review of the new Tesla S first drive, according to the reviewer, the new Tesla has such a low center of gravity, there is simply no concern of weight transfer at the corner no matter how aggressive you take it.

Is it possible that a car with low enough center of gravity your conventional driving school instructions no longer apply, at least in street conditions where you will never get the chance to push the car into a corner at 100 mph?
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Old 07-02-2012, 05:27 PM
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No. Typical "reviewer" auto-journal's ignorant bull-crap. Anything on a sprung system will have to obey the laws of vehicle dynamics, and it's a very unforgiving law...Even go-karts will have to adhere to weight transfer rules.
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Old 07-02-2012, 06:09 PM
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No. Typical "reviewer" auto-journal's ignorant bull-crap. Anything on a sprung system will have to obey the laws of vehicle dynamics, and it's a very unforgiving law...Even go-karts will have to adhere to weight transfer rules.
Simply get an older model car that was built before the vehicle dynamic laws were passed,

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Old 07-02-2012, 08:02 PM
dtc100 dtc100 is offline
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No. Typical "reviewer" auto-journal's ignorant bull-crap. Anything on a sprung system will have to obey the laws of vehicle dynamics, and it's a very unforgiving law...Even go-karts will have to adhere to weight transfer rules.
Will a race car driver in a Formula 1 car have to obey the same rules when entering a corner at 45 mph (yes at 45, not 145 mph) to avoid a spin out of control? There has to be different rules for cars with different physics. Again, I am not trying to go fast, just figure out how safe it is to have some fun.

Doing donuts and burnouts can be fun, and can be done safely, without going anywhere at all. Although clearly a different set of rules must apply.

Last edited by dtc100; 07-02-2012 at 08:07 PM.
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Old 07-03-2012, 04:03 AM
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CALWATERBOY CALWATERBOY is offline
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Originally Posted by dtc100 View Post
I have read a review of the new Tesla S first drive, according to the reviewer, the new Tesla has such a low center of gravity, there is simply no concern of weight transfer at the corner no matter how aggressive you take it.

Is it possible that a car with low enough center of gravity your conventional driving school instructions no longer apply
, at least in street conditions where you will never get the chance to push the car into a corner at 100 mph?
Interesting thread.

A big negatori & +1 to The HACK. Although a very low CG will minimize weight transfer problem dynamics, the laws of physics, curse them, still apply.

Pretty good ref's:

Of course, rear issues such as wheel hop and handling characteristics in general, 335i/328i, can be resolved w/part replacement.

For OP: M-Rated's hand position advice makes those paddles work well if you remember which way's up & which down - left paddle / right paddle's more intuitive when driver's gotta think fast IMHO - less an issue if using the stick but control's sacrificed. Have to admit I prefer the stick on public roads!

.

Last edited by CALWATERBOY; 07-03-2012 at 04:05 AM.
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Old 07-03-2012, 08:20 AM
dtc100 dtc100 is offline
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The manual mode in the AT 328i simply does not react fast enough to driver's input to be a fun factor. I was forced to play with all possible tricks in the SD mode. The 335i AT tranny might be better, but there is much less different feel between the D and SD modes in a 335i, whereas the two modes offer two very distinct personalities in a 328i.

Throttle blip and kickdown are the two obvious tricks, but the amount of force applied to the pedal can also control when the ECU shifts gears.

As far as law of physics, it will always be there, but it's significance may no longer be there as much. In a Tesla S with fat tires, I seriously doubt you have to worry about loss of traction entering a corner at 45 mph.
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Old 07-03-2012, 09:04 AM
hyperzulu hyperzulu is offline
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Originally Posted by CALWATERBOY View Post
For OP: M-Rated's hand position advice makes those paddles work well if you remember which way's up & which down - left paddle / right paddle's more intuitive when driver's gotta think fast IMHO - less an issue if using the stick but control's sacrificed. Have to admit I prefer the stick on public roads!
The LCI cars are left/down, right/up.
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Old 07-03-2012, 09:13 AM
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CALWATERBOY CALWATERBOY is offline
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Originally Posted by dtc100 View Post
The manual mode in the AT 328i simply does not react fast enough to driver's input to be a fun factor. I was forced to play with all possible tricks in the SD mode. The 335i AT tranny might be better, but there is much less different feel between the D and SD modes in a 335i, whereas the two modes offer two very distinct personalities in a 328i.

As far as law of physics, it will always be there, but it's significance may no longer be there as much. In a Tesla S with fat tires, I seriously doubt you have to worry about loss of traction entering a corner at 45 mph.
Wow! Shoulda assumed - pretty good point.

I find big diff ZF's D / DS; stock sport suspension less than what I like on any but totally unblemished, new pavement. Mods cured those suspension issues. That said, 4 electric motors should grossly out-class conventional drive trains - combined w/magneto rheological shocks and, if totally cool, 4 just-in-time radars. Cryin' shame energy density nowhere near.

What's Tesla's expected range, driven for fun?

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Old 07-03-2012, 09:37 AM
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captainaudio captainaudio is offline
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The laws of vehicle dynamics and physics are constant. Regardless of the "cornering on rails" claims that you see posted here there is always some slippage as a car is cornering regardless of how fast the corner is being taken.
This can be demonstrated by taking the car to a large empty parking lot and driving in a circle while holding the steering wheel perfectly still. As you speed up the radius of the circle will increase and as you slow down the radius will decrease.

Poor driving techniques are poor driving techniques and the fact that you can get away with them without unsettling the car when you are well below the limits does not mean that they are not poor driving techniques. Also the laws of physics and vehicle dynamics are the same whether you are on a track or public roads.

As an example, snapping off the accelerator while turning will unsettle the car, shift the weight to the front of the car, increase the size of the front contact patches and decrease the size of the rear contact patches. Obviously the results of this are going to be different when the car is cornering at low speed and is nowhere the limits of adhesion than when the car is using most or all of the available grip to turn. In that situation snapping off the accelerator will cause the car to spin out. You never want to do anything sudden. Brakes pedals and accelerators are not on off switches and should be applied smoothly and progressively.

Grip is finite and if all of the available grip is being used for braking there will be none left for turning.

There is a very good visual tool called the Friction Circle that expalins how this works.
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  #23  
Old 07-03-2012, 09:40 AM
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Speedwagon Speedwagon is offline
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Originally Posted by dtc100 View Post
I consider our E90 328i AT the last batch of fun cornering sedans for street driving. A good compromise for many who must share the car with manual-hating spouses or SOs.

While I totally agree with the above assessment for track and autox, it takes out a lot of fun in street conditions, because in street driving you rarely get to the point of letting the tires break loose under the speed limits, even if you take on a band or corner at 20 mph above, especially if you have a set of good summer tires. Not that I do it but this is just how I think your tire grip should be at a minimum.

The most fun is to first make sure it is safe, no traffic around, then quickly approach and just as you begin the turn, hit the brakes hard, and release it as you just about to come out of the corner but before the car straighten itself.

If you want to add some manual driving feel to it, use what they call "throttle blip" in the sport mode (works in standard mode also but I doubt you are in that mode at this point anyway). Before braking, quickly tap the throttle, if you do it right, the tranny will shift to a lower gear and hold it while you corner.

The throttle blip needs some practice to activate consistently. If it does not trigger it can be awkward. But if it works, can be a lot of fun. I am at the point I can make it work 80% of the time.

I don't use manual mode for this, it is too slow to react to your shift.

Keep in mind this is to assume your tires will chirp but are never loose in such action, and your traction control is not turned off.
I tried the throttle blip that described in your post, It was great! I didn't know it would do that Thanks for the post. Comes in handy on the fast roads here in Europe!
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Old 07-03-2012, 09:45 AM
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CALWATERBOY CALWATERBOY is offline
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The LCI cars are left/down, right/up.
Latest LCI, yes - as God intended.
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Old 07-03-2012, 10:50 AM
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Mark K Mark K is offline
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Poor driving techniques are poor driving techniques and the fact that you can get away with them without unsettling the car when you are well below the limits does not mean that they are not poor driving techniques. Also the laws of physics and vehicle dynamics are the same whether you are on a track or public roads.
Very true. The difference is when you KNOW that what you are doing is a poor driving technique vs doing it without knowing. In the first case you WANT to be an idiot, in the second case you are just an idiot. Big difference because, as Churchill once famously said, "True, but I'll be sober tomorrow."

The opposite is also perfectly true. Just because soccer mom's minivan brake lights go off at the apex doesn't mean she is trailbraking.

My favorite idiot moment is with crappy handling FWD cars where I intentionally bring fronts to the grip limit (VERY easy with crappy handling FWD cars) at the apex and then turn off the throttle like a switch. Stupid, but huge fun, especially on a low grip surface.

To OP, what ///M said is the way to do it properly. Once you know that, you can try and do stupid fun stuff.
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