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whiskychaser
08-02-2009, 10:23 AM
Kickdown switch works but your foot has to be fairly hard down before it changes down. The effect is that the car goes off like a scalded cat in S mode and its best to make sure you are holding the steering wheel firmly. I can twiddle with the height of the switch to my heart's content but wondered if anyone has come across a measurement for the distance between the back of the throttle pedal and the top of the switch?

whiskychaser
08-02-2009, 01:34 PM
Did some experimenting and the cause of the scalded cat (SC) mode is pretty clear: At about 40mph the car is in 4th gear doing around 2000rpm. Put your foot down firmly and it drops to 3rd gear and the revs go up to 2500-3000. BUT if you put your foot down firmly you can also cause it to drop TWO gears. I'm now in second gear so no wonder it takes off! ( In E mode it changes up from second to third at 20mph)
Any advice on the difference between the 'firm' pressure that causes one gear shift and the 'firm' pressure that causes two would be appreciated

leicesterboy15
08-02-2009, 04:53 PM
Hmm...

I will check tomorrow :)

bubba966
08-02-2009, 08:09 PM
Did some experimenting and the cause of the scalded cat (SC) mode is pretty clear: At about 40mph the car is in 4th gear doing around 2000rpm. Put your foot down firmly and it drops to 3rd gear and the revs go up to 2500-3000. BUT if you put your foot down firmly you can also cause it to drop TWO gears. I'm now in second gear so no wonder it takes off! ( In E mode it changes up from second to third at 20mph)
Any advice on the difference between the 'firm' pressure that causes one gear shift and the 'firm' pressure that causes two would be appreciated

You're saying you don't like the double downshifting? That's a performance function.

mzarifkar
08-03-2009, 08:32 AM
The effect is that the car goes off like a scalded cat

vivid imagery, experience in the matter? lol

whiskychaser
08-03-2009, 02:41 PM
vivid imagery, experience in the matter? lol
I didnt make it up - its an expression:D I think if you were to use this 'performance function' in a bend you would be very likely to follow the cat in a fast excursion into the bushes.

leicesterboy15
08-03-2009, 04:16 PM
Well I did some reaserch today - in the name of science of course! My extensive research identified that when your foot is all the way down there is a second notable level that allows you to push further and engage the 'maniac' mode. Watch the speedo shoot up rapidly and the fuel gauge go down just as fast.

I'm sure you don't always need to push past the first bit for it to kick down if there are enough revs left 2 gears down and similarly if the revs would be too high it will not drop 2gears and I imagine it depends on your engine and box - my car only has A (adaptive) and S (**** yourself), no E mode.

tim eh?
08-03-2009, 07:24 PM
hey guys is it possible that one setting is controlled electronically and the other by the throttle cable?

I don't think it is the same in an m20... I don't have the wire under the carpet and my kickdown only ever drops one gear. It is triggered by the throttle cable at the throttle body, which I only know through trying to watch my mechanic adjust it while I moved the accelerator pedal. The reason he was adjusting it was because of this leak, which I was told was caused by the increased play in the throttle cable. (shrug? - he fixed it for cheap anyway...)
http://www.bimmernut.com/forum/attachment.php?attachmentid=5567&stc=1&d=1249344900

Not sure if it's an issue for you guys or not- I was going to stay out of this thread because mine is different and I hope this is not relevant to you. Here is the realoem page for my cable-to-tranny rig anyway.
http://www.realoem.com/bmw/showparts.do?model=HC23&mospid=47402&btnr=24_0763&hg=24&fg=15

whiskychaser
08-04-2009, 04:32 PM
hey guys is it possible that one setting is controlled electronically and the other by the throttle cable?
I don't think it is the same in an m20... I don't have the wire under the carpet and my kickdown only ever drops one gear. It is triggered by the throttle cable at the throttle body, which I only know through trying to watch my mechanic adjust it while I moved the accelerator pedal. The reason he was adjusting it was because of this leak, which I was told was caused by the increased play in the throttle cable. (shrug? - he fixed it for cheap anyway...)

Not sure if it's an issue for you guys or not- I was going to stay out of this thread because mine is different and I hope this is not relevant to you. Here is the realoem page for my cable-to-tranny rig anyway.
http://www.realoem.com/bmw/showparts.do?model=HC23&mospid=47402&btnr=24_0763&hg=24&fg=15
There is no cable from the throttle linkage to the tranny on mine. The owners' manual says it should only drop one gear but I think its generic. Until Leicesterboy said his did the same I thought it was a fault. I'd thought the kickdown switch was a simple short to ground but clearly not. Will have to go through all my files to see if I can find out how this works. TBH if you have dropped 2 gears and are running at about 5000rpm it doesnt feel like there is a lot left to give:D