RT article on transmisions..

[jtace]

http://www.roadandtrack.com/technical/ArticleDisplay.asp?ArticleID=139&page=1

I found this article to be very interesting. Good read, both about F1 style shifting in general and BMW's specific system. :)

[Spiderman]

Interesting. Most of it went over my head though :(

I don't know if this is the same as semi automatic. I read something about "semi automatic" gears being introduced in f12002. They say that the gears will work normally in automatic mode for upshifting but down shifting can be done manually.

[DC_Targa]

Great article. This is exactly what I want in my next car... Something that is not a pain in stop and go traffic, but something that has paddle shifters for the back roads.

Those of you that have read my "what's new" page on my site, you will know my 76 Targa has a "Sport-a-matic" transmission. It is a technically poor version of a semi-auto, having both a torque convertor and a vacumn actuated mechanical clutch triggered by pre-travel lever motion of the all-to-long a throw shift lever. Upshifts are fine, but aggressive downshifts require a lot more finesse than a normal manual transmission. I can just imagine how much driveability would improve if it had a good close-ratio, 6-speed, paddle shifting box like in the article.

Enough dreaming... Back to work.

DC_Targa

[KyzrSoze]

Wow, Targa! I hope that you dont put too many miles on that car. The Porsche mechanic must be drooling over the prospect of billing you for that transmission rebuild!!:D

[jtace]

Yeah that's what I'd like to have on my next car too.. :)

[Wazza]

can i put one of these on a classic mini.. :D

They tell you about the technology, I can tell you how it works, in practice on the new BMW M3!


1. Select Manual mode 6 (the fastest and sharpest shift program)
2. Hold gear lever forward
3. Floor the throttle (engine revs rise to about 3500rpm)
4. Let the gear lever go.
5. M3 rockets away
6. Now just keep pulling back on the gear-selector each time the engine reaches 7900rpm.

You must remember on the M3 that it's gearbox is set up like the old 2 litre Touring cars, you pull back to upshift, and push forward to downshift.

But, if you don't believe me, see the following video, which demonstrates it:

http://www.bmwclub.org.hk/gallery/videostreaming/smg2_video/MOV00071.MPG

The system is designed to:

"Provide near motorsport levels of acceleration on surfaces affording sufficient levels of grip."

This quote from the BMW M3 (SMG) owners handbook.

It should also be noted that the SMG II gearbox in the new M3 has 6 auto-shift modes (where it works just like a auto gearbox), and 6 manual modes where it is a straight sequential gearbox. The modes are organised from 1 to 6 in terms of shift speed and feel. 1 delivers very smooth gear shifting, whilst 6 delivers very fast gear shifts, like you'd achieve in a race car with a sequential gearbox.

[DC_Targa]

KyzrSoze,

You do know who my Porsche mechanic is, don't you? :)
He works real cheap. Usually for beer and peanuts. He's the same guy that built my off-road race engine, gearbox, etc. He's also the nut behind the wheel.

You may have seen the 3 car workshop on my "home" page. Well, in there ya might just find an engine hoist, arc welder, gas welder, lathe, drill press... even a rig to CC heads.

So the mechanic comes cheap. I wish I could say the same for the parts. Have a look around http://performanceproducts.com and you will see the real fun in owning a Porsche.

DC_Targa