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      06-26-2009, 06:59 PM   #23
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Quote:
Originally Posted by Terrance28 View Post
Then be in the right gear for the turn the car will only kickdown if there is room in the rpms to drop down to safely.
Not true, how does it know when to drop-down safely? Its not like it knows your in a tight turn and shifting down will upset the balance. The kickdown wouldn't be a big deal if you could disable it....for god's sake: when your in manumatic mode why the does it kick down..that makes no sense. With the gobs of torque, shifting down doesn't always make things quicker.
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      06-26-2009, 07:06 PM   #24
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Quote:
Originally Posted by 335lvr View Post
Not true, how does it know when to drop-down safely? Its not like it knows your in a tight turn and shifting down will upset the balance. The kickdown wouldn't be a big deal if you could disable it....for god's sake: when your in manumatic mode why the does it kick down..that makes no sense. With the gobs of torque, shifting down doesn't always make things quicker.
I think he meant if the engine still has some room to downshift without going over redline it will if you kickdown. If you're already in a low gear at high rpm and try to kickdown it won't downshift because that will over rev the engine.

I don't understand what the big deal is? Don't hammer your foot down and it won't kickdown. Just put enough pressure down to not trip the kickdown you still get 100% WOT without a downshift. I think kickdown was put there for safety reasons. If you have some noob driving in manumatic in too high of a gear and suddenly realizes he needs to accelerate quickly, kickdown will put him in the right gear.
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      06-26-2009, 07:23 PM   #25
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In a different thread, somebody explained the concept:
The button is a placebo and it does not help to remove it.

The throttle angel before the click is 90-95%, upon full throttle, which is when the button is pressed down, the ecu detects the 100% angels, shifts down and gives full power. (even a bit above standard turbo pressure if I understood well)

This seems to be different from a MT....
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      06-26-2009, 08:49 PM   #26
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Quote:
Originally Posted by 335lvr View Post
Not true, how does it know when to drop-down safely? Its not like it knows your in a tight turn and shifting down will upset the balance. The kickdown wouldn't be a big deal if you could disable it....for god's sake: when your in manumatic mode why the does it kick down..that makes no sense. With the gobs of torque, shifting down doesn't always make things quicker.
What the hell are you talking about. The car is controlled by a computer how wouldn't it know what's a safe gear to drop too. What I meant by it will drop down to the safest gear is simple. If you are in the right gear at the right rpms for the turn it won't kickdown if it doesn't have too.
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      06-26-2009, 08:51 PM   #27
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Quote:
Originally Posted by hsleiman View Post
I think he meant if the engine still has some room to downshift without going over redline it will if you kickdown. If you're already in a low gear at high rpm and try to kickdown it won't downshift because that will over rev the engine.

I don't understand what the big deal is? Don't hammer your foot down and it won't kickdown. Just put enough pressure down to not trip the kickdown you still get 100% WOT without a downshift. I think kickdown was put there for safety reasons. If you have some noob driving in manumatic in too high of a gear and suddenly realizes he needs to accelerate quickly, kickdown will put him in the right gear.
Thank you very much.
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      06-26-2009, 09:47 PM   #28
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Quote:
Originally Posted by Terrance28 View Post
What the hell are you talking about. The car is controlled by a computer how wouldn't it know what's a safe gear to drop too. What I meant by it will drop down to the safest gear is simple. If you are in the right gear at the right rpms for the turn it won't kickdown if it doesn't have too.
LOL. It's not as simple as that on a track...I'm sure its fine for street driving. You are talking safe kickdown for the engine/tranny and I'm talking safe kickdown while in a turn ...two different things.

LOL again for kickdown for safety reasons...in case someone has to accelerate quickly??

I am positive I would be able to adapt to know where the threshold for kickdown is, but I still think it is very dumb.
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      06-26-2009, 10:07 PM   #29
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Quote:
Originally Posted by 335lvr View Post
LOL. It's not as simple as that on a track...I'm sure its fine for street driving. You are talking safe kickdown for the engine/tranny and I'm talking safe kickdown while in a turn ...two different things.

LOL again for kickdown for safety reasons...in case someone has to accelerate quickly??

I am positive I would be able to adapt to know where the threshold for kickdown is, but I still think it is very dumb.
Umm yes for safety reasons I can immediately think of 2 or 3 situations where it would be beneficial to accelerate quickly. Some might argue the ability to accelerate quickly is just as important as the ability to slow down quickly when attempting to avoid an accident.

Also, if you are tracking your car I hope you possess the fine motor skills needed for throttle modulation and if you were in the right gear when exiting a turn kickdown should not be a factor. And if you track your car you might want to consider getting a stick. Auto boxes were devised so less input from the driver would be needed and on a track I would think that you would want as much control over your car as possibe.
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      06-26-2009, 11:31 PM   #30
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Quote:
Originally Posted by Mr. 5 View Post
Then can you explain why an auto has this button and the manuals don't?
If there isn't an actual button then why even have it?
It's for people who are used to driving cars back in the day that actually had a switch that you could feel. It's a placebo.
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      06-26-2009, 11:36 PM   #31
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Quote:
Originally Posted by 335lvr View Post
Not true, how does it know when to drop-down safely? Its not like it knows your in a tight turn and shifting down will upset the balance.
It absolutely does know if you're in a tight turn and shifting will upset the balance. It uses several sensors. Steering angle sensor, DSC rotation rate sensor, and other inputs to know that you're in the middle of a turn, and will do it's best to keep the same gear.
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      06-26-2009, 11:41 PM   #32
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Quote:
Originally Posted by 335lvr View Post
LOL. It's not as simple as that on a track...I'm sure its fine for street driving. You are talking safe kickdown for the engine/tranny and I'm talking safe kickdown while in a turn ...two different things.

LOL again for kickdown for safety reasons...in case someone has to accelerate quickly??

I am positive I would be able to adapt to know where the threshold for kickdown is, but I still think it is very dumb.
I understand what you are saying, but the easy solution is if you are in the right gear when you are going through a corner the kickdown feature is not an issue because the car would not need to kickdown because you are already in the right gear to accelerate out of it.
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      06-27-2009, 12:11 AM   #33
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Quote:
Originally Posted by SoCalTech View Post
It's for people who are used to driving cars back in the day that actually had a switch that you could feel. It's a placebo.
No it's not. The purpose of the kickdown is to put your car in a low enough gear to maximize acceleration. This is the same as flooring it in any other auto car. You floor it, the car will downshift, and you will accelerate. BMW has chosen to incorporate the "kickdown" feature to fine tune the behavior of the vehicle. If you want to accelerate without downshifting, you can push the pedal to the resistance point. If you want maximum acceleration and the car to behave just like any other car when you floor it, you push past the resistance point to engage kickdown. Obivously, manual transmission cars do not need this feature as the shifting is controlled solely by the driver and not the ecu.
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      06-27-2009, 12:28 AM   #34
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The "button" that you feel is a placebo. Take the pedal apart and see for yourself. There is no message sent to the DME saying "the kickdown button was pushed". There is no wiring, sensor, or signal associated with the actual feeling of pushing the "kickdown switch".
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      06-27-2009, 01:03 AM   #35
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Somewhat unrelated, but I was surprised that the Saturn Vue SUV will hold the gear, at redline, when in manual mode and full throttle! At least in 1st gear, I didn't test any of the others specifically, but I don't remember it kicking down when mashing the accelerator.

It was a Hertz rental car, otherwise I'd never get close to the thing.....
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      06-27-2009, 01:24 AM   #36
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Quote:
Originally Posted by SoCalTech View Post
The "button" that you feel is a placebo. Take the pedal apart and see for yourself. There is no message sent to the DME saying "the kickdown button was pushed". There is no wiring, sensor, or signal associated with the actual feeling of pushing the "kickdown switch".
"Placebo" or not, the car still behaves the way I described.
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      06-27-2009, 02:06 AM   #37
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To the OP:

Do this:

http://www.e90post.com/forums/showth...sable+Kickdown
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      06-27-2009, 08:39 AM   #38
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just buy a manual and you don't have to worry about your car driving you :P
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      06-27-2009, 08:41 AM   #39
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According to OBDII data, the car is at full throttle before the kickdown is pressed... pushing the "button" does not open the throttle plate any further in my testing. The last bit of pedal travel (the kickdown) tells the car to downshift.
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      06-27-2009, 11:38 AM   #40
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Quote:
Originally Posted by RiXst3r View Post
According to OBDII data, the car is at full throttle before the kickdown is pressed... pushing the "button" does not open the throttle plate any further in my testing. The last bit of pedal travel (the kickdown) tells the car to downshift.
So using that block of wood really does work, I would have never believed it, haha.
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      06-27-2009, 02:26 PM   #41
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Quote:
Originally Posted by RiXst3r View Post
According to OBDII data, the car is at full throttle before the kickdown is pressed... pushing the "button" does not open the throttle plate any further in my testing. The last bit of pedal travel (the kickdown) tells the car to downshift.
THANK YOU. Damn people is it that hard to understand.
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      05-10-2015, 05:06 PM   #42
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[u2b]http://www.youtube.com/embed/dOR4GQYnAx8[/u2b]
http://www.youtube.com/watch?t=36&v=dOR4GQYnAx8


Man there seems to be a lot of confusion about the kick down switch, which I guess is understandable because I don't think it's documented at all in the car's manual. But you guys are like a bunch of bad scientists, a lot of different theories, but no one's bothering to test.

I made this video today to explain what the kickdown switch does, how it's different than 100% throttle, and how it's not a 'placebo' It's a really cool feature in both automatic and 'manual' mode.


Quote:
Originally Posted by Martinmaxx View Post
When you drive a 6MT you do not always want to downshift to the lower possible gear when pressing the gas pedal all the way. Specially with cars such as a 335i that have loads of torque al low revs. That is why some people (including myself) prefer to disable the kick-down button while driving the steptronic in manual mode.
I'm surprised you and others feel this way, mostly because the 'switch' has a good amount of resistance. So much that I can effortlessly 'floor it' without engaging the switch. I had my car for a year now and floored it all the time, only just noticed the other week that I could push it further.

Quote:
Originally Posted by Mr. 5 View Post
Then can you explain why an auto has this button and the manuals don't?
If there isn't an actual button then why even have it?
A manual wouldn't have this button because a manual is... manually downshifted. This button is 100% and ONLY about automatic downshifting.

Quote:
Originally Posted by 335lvr View Post
The kickdown wouldn't be a big deal if you could disable it....for god's sake: when your in manumatic mode why the does it kick down..that makes no sense. With the gobs of torque, shifting down doesn't always make things quicker.
This is an awesome feature for manumatic! WTH are you talking about :P. In a real manual car when you downshift, many times you would skip a gear. You might go from say 6th directly to 4th. With manumatic you can't do this. That's why on manumatic and SMG for M3 there is a kickdown switch. This allows you down skip gears when downshifting in manumatic or SMG.

Quote:
Originally Posted by rismo View Post
In a different thread, somebody explained the concept:
The button is a placebo and it does not help to remove it.

The throttle angel before the click is 90-95%, upon full throttle, which is when the button is pressed down, the ecu detects the 100% angels, shifts down and gives full power. (even a bit above standard turbo pressure if I understood well)

This seems to be different from a MT....
This is incorrect as explained above and in my video. If you remove it with the wooden block like some people do, it's disabling the kickdown shifting logic, plain and simple.

Quote:
Originally Posted by RiXst3r View Post
According to OBDII data, the car is at full throttle before the kickdown is pressed... pushing the "button" does not open the throttle plate any further in my testing. The last bit of pedal travel (the kickdown) tells the car to downshift.
I agree with this completely. Other than to say, pressing down fulling WITHOUT kickdown will also tell it to downshift, just to a higher gear.

Quote:
Originally Posted by SoCalTech View Post
There is no kickdown button/switch. There is a detent built into the pedal to be a placebo, but there is no actual switch/button/wiring/sensor/signal related to it.
This is false, read above and watch the video.

Quote:
Originally Posted by SuPaSkillz View Post
+10.....If i wanted it to go into a lower gear I have paddles on the steering wheel for that. I would like to floor my car with out it kicking down to a useless gear that will last about two sec.
You can't skip gears when downshifting with the paddles. Thats the point of this switch.

Quote:
Originally Posted by SoCalTech View Post
It's for people who are used to driving cars back in the day that actually had a switch that you could feel. It's a placebo.
Nope.

Quote:
Originally Posted by hsleiman View Post
This is the same as flooring it in any other auto car.
Note quite true and I demonstrate this in my video. In automatic mode you can still "floor it" and it will downshift and behave like any other auto. The kickdown switch takes that to the next level. If you're cruising on the highway in 6th and floor it, it will downshift to 4th. If you instead floor it and mash down the kickdown switch it will downshift to 3rd.

One point, perhaps is if I'm not mistaken peak horsepower on the e90's inline 6 is in the 5-6K range. Which is what this gets you to.

Also at base value this now offers you two kinds of passing modes or acceleration modes. You can floor it like normal, taking you from 2000 RPM to 4000 RPM. You can floor it past the point of resistance which takes you from 2000 RPM to 6000 RPM. Or you can do 4000 first, and still go to 6000 if you decide you want it. IMO great feature for an automatic transmission. More control considering.

Last edited by ssshake; 05-10-2015 at 07:14 PM..
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