Re: how does it work? Some detail. (archive)

: : : but then would manual clutch and a stick shift would really be a "true manual"?
: : : And how different is it for the driver? I have driven stertronc bimmers before and it was not nearly as much fun as a regular manual. It gave a lot less control of what's going on. How is SMG different from that? What exactly is changed by the lack of the torque converter? Does it give the same control of the car?

: I'll try to give you a quick overview of the torque converter. Imagine placing two common house fans face to face. When you turn one on, the other will begin rotating because of the blowing air reacting to blades on the other fan. Notice that the second fan does not spin as fast as the fan that is powered, this is the concept of "slippage". Now imagine these fans made in a housing, with many more blades and the air replaced with transmission fluid. The more viscious fluid will transmit the rotation from the engine to the trasmission much faster than the air, but there is still slippage occuring. Once the transmission catches up to the engine the slippage is minimal. This slippage is what makes the automatic transmission feel so smooth, but it also loses power, therefore less gas milege. Picture a torque converter that has a slippage of 5% (I'm not sure of the typical values) with an engine output of 300 HP, you lose 15 hp through the transmission. In defense, torque converters are availabe that "lock-up" after a certian RPM is reached.

: In contrast, with a manual transmission the clutch is in direct contact with the flywheel. And unless the clutch is not designed with the correct surface area and pressure for the application, there is no slippage once the clutch pedal is fully released. So, as someone said before, all of the power is transmitted to the rear wheels.

: The SMG provides the all of the power through the use of a conventional clutch, but the convience of a automatic transmission through the computer actuated clutch and engine RPM syncronization. There was a good article in the BIMMER magazine a few months ago describing the SMG. (If you want the exact issue, I can find it). The SMG can be shifted, currently with a stick up or down through each gear one after the other. (Picture a video game, where you must go from first, to second, to third with the push of a button, without the option of going from first to third)(Also used in Formula one Racing) The new reports say the gear stick will be removed and replaced with paddles or buttons on the steering wheel, one shifts up, the other shifts down. But there is also the option to put it in an automatic mode and just drive it like an automatic. (At least that is what the article says). Pretty much providing you with the best of both worlds. Fun driving when it is needed and automatic shifts when you are eating or relaxing.

: Hope this helps.
It helps a lot - thanks!
However, what exactly stopped them from doing it like this from the very beginning? Just the fact that it's harder to drive or something? Or that it's more expencive?

Follow Ups:

Re: how does it work? Some detail. Richard Peterson 15:44 9/23/99 (1)
- Here's how it works Pete 01:10 9/24/99 (0)
too expensive...more Gilbert 12:54 9/23/99 (6)
- Gilbert is correct... Bruce 14:10 9/23/99 (5)
  - Cost in Europa approx. US$ 2900 depending on exchange rate used (eom) 00:53 9/24/99 (0)
  - bubbaclub.com/rob.....click on "articles" Den 21:00 9/23/99 (0)
  - typo(again)...use this link Den 20:57 9/23/99 (0)
  - typo...use this link Den 20:54 9/23/99 (0)
  - SMG Articles Den 20:51 9/23/99 (0)

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