norb

SMG only down shifts automaitcally if you're about to bog your engine down because of low revs. If you are driving this way in an autocross or a track, you might want to go to a driving school.

krispykrme

No. Here is the problem I have. If i manual down shift. Especially down shifting more than 1 gear at once. SMG does not respond well to that. In addition, it's actually a very jerky down shift, which increases chance of losing control. If you drive SMG hard, it does not really respond that smoothly.

norb

Dude, I don't know what the heck you're talking about, SMG is tailor made for autocrossing and for the track. You're complaining about jerkiness while tracking your car? Are you freaking serious? Do you also gingerly apply brakes? Have you ever done any steering corrections?

Yes around town SMG isn't the smoothest, but you keep bringing up autocross and track use, I'm begining to doubt you've done either.

krispykrme

No, I don't gingerly apply the brake. However, this does not mean I particularly enjoy uneeded jerkiness from rough down shift of SMG.

My point is that I would much prefer a clutch pedal because I could done it smoother (not faster). Yes, I admit that I am not used to SMG's timing.

What does this has to do about my complaints. All I am stating is that compare to manual, SMG at track although shifts faster than I could ever down. It's not a smooth operation.

I am getting fed up by a lot of your response. You are taking my comment way out of context.

All I am saying is that, during tight turns, it's very difficult to time the SMG to have a smooth turn and not cog up your engine. I just found the true manual easier and smoother to deal with. I am not stating that SMG does not have its performance advantages. It's lightening fast and smooth for upshift. But for down shift, especially for more than 1 gear, SMG just falls flat on its face.

You don't see me complain about the upshift.

smgC32

It could be than you are not downshifting at the correct rpm range for the next lower gear? I have driven many SMG equiped cars at the track and have never experienced the problems you are experiencing. Then again, I have never let the computer take control of the downshifting for me and allowed the rpm's to drop to such a low level that the computer must down shift three gears for me before the car stalls while in mid corner and coasting, as there is neither power or brake application happening during this computer pause.

Drive the SMG transmission just like a manual with the same shift points and they should be smoother than a manual for most drivers, unless you are really good at heal and toeing. Most slow turns from a fast straight away will require a minimum of two if not three downshifts prior to turn in. While in the brake zone, you should have completed your first 5th-4th downshift while hard on the brakes. As you approach the end of the brake zone, you should have completed your 4th-3rd downshift as you enter the turn with some throttle input. You may even need to downshift from 3rd-2nd just prior to turn in as you may also elect to trail brake into the corner to adjust final entry speed and car attitude as you aim for the apex.

You are doing something wrong in your utilization of the SMG transmission on the track. Even on the street, if you learn your shift points, the SMG will shift very smoothly, as smooth as a good manual shifting. Some people even heal and toe their SMG tranny to help out the computer if their shift points are not within range. Good luck on your learning curve.

krispykrme

It really depends on the turn itself. Yes, ideally you should be able to have enough time to allow yourself time to down shift twice (one gear at time). However, in the case your describe, when shifting from 4th to 3rd and onto 2nd. The SMG will take a long time to rev match. And the shift timing is much different if you are doing one upshift. I just had a difficult time adjusting to that.

If you down shift too quickly through two gears, you really can't time the shift point that well. Upshifting is quiet easy to time and drive smoothly. I just did not like the downshift. I would much prefer true manual.

smgC32

If you drive the SMG like a manual (which it is, technically), the timing is no different. What most people do with the SMG is drive it like a auto tranny, which it is not. Some think that you can just paddle your way through the gears without any pause when downshifting like a traditional auto tranny or the MB unit.

An immediate 5th to 2nd gear shift cannot happen in either a SMG or manual under the same circumstances. If you are at 7,000rpm in 5th, you cannot just paddle down three gears immediately and expect the car to select 2nd on command. Either tranny would explode in this situation. If you try this manuver, there will be a long lag before the speed drops off to a safe level to shift gears. If it is taking a long time to match rev's, then you are shifting too early. Would you have shifted at the exact same moment in a 6 speed manual tranny during your heal toe braking? For those that don't heal toe and ease the clutch out during downshifts, the shift time is greatly lengthened and the shift becomes much more jerky and unsettles the car. If you learn the sweet spots for each upshift and downshift in each gear, then the timing of the shift provides a very fluid up or down shift in the SMG tranny. It just takes some time to get good at it.

Have someone who has perfected the downshift with the SMG tranny take you for a ride and demonstrate its fluidness. Or stop by any BMWCCA driver's school and ask one of the instructors to take you for a hot lap in their SMG equipped car. Or better yet, sign up for the whole day and practice for hours in a safe environment.

norb

smgc32 forget about debating logic with KK, you'll never win.