Any SMG experts in the house?

[dirtboy]

I know SMG, SMT, etc (semi-automatic) transmissions from the F1 racing world are starting to show up, but I don't completely understand how they work. The manufacturers always brag about how fast the car can shift, but how does the engine drop revs fast enough to meet the ultra fast shift times?

I know with my car, depending on gear, I need to drop approximately 1,500 rpms for the next gear to be smooth. I can't force the engine to drop revs, so I have to wait, but a SMG doesn't wait.

 

[FeathersMcGraw]

You mean this isn't a Sarah Michelle Gellar thread?

 

[Zenmervolt]

From what I can understand, it's fancy engine management combind with a well-modulated clutch takeup. I think the main thing it the clutch modulation by the hydraulics.

ZV

EDIT: What I mean is that with an SMG, the engine management knows that the shift is going to happen even before the shift happens, so the throttle can be controlled much more precisely than with a standard transmission.

 

[LiQiCE]

Not an expert on SMG at all, but I remember being told that the M3 SMG-II when in "race" or "sport" mode (which means shift fast) ... the engine shifts are not smooth at all (they're actually pretty rough) ... But when you're in one of the normal driving modes of the M3 SMG-II it will shift smoother, and I'm assuming less aggressively. Don't know if that helps answer your question or not..

 

[dirtboy]

Ah... if the shifts are rough, then the transmission must be shifting early and forcing the engines revs down. Interesting.

 

[SithSolo1]

Uhh, I guess this isn't about Counter-Strike either. =(

So what is a, non-Sarah Michelle Gellar/non-Sub Machine Gun, SMG?

 

[LiQiCE]

SMG = Sequential Manual Gearbox.

Essentially its a new type of transmission for cars which works like a manual transmission, but the clutch and shifting is controlled by a computer. (At least on the M3, the clutch and shifting can be controlled by the computer with the option of the driver controlling shifts. In the new Toyota MR2 the shifting is always manual with the clutch being computer controlled).

 

[MercenaryForHire]

Count in another sucker/hopeful who was thinking that SMG = Small Machine Gun.

You mean you don't want to talk about why the SWAT teams have switched away from the MP5SD series to a 5.56 carbine?

- M4H

 

[ChefJoe]

Yummm, Buffy....

 

[Hammer]

its the same as the steptronic but mounted on the steering column, not a heck of a lot of difference other than the coolness factor.

 

[minus1972]

I'm not sure that it is the same as the steptronic, I thought that this was more like a computerized manual transmission where the steptronic was an automatic that you could shift when you wanted to.

 

[FuZoR]

Originally posted by: FeathersMcGraw
You mean this isn't a Sarah Michelle Gellar thread?

i was thinking the same

 

[LiQiCE]

Originally posted by: Hammer
its the same as the steptronic but mounted on the steering column, not a heck of a lot of difference other than the coolness factor.

Steptronic IIRC is basically an automatic transmission that allows you to shift to different gears. SMG is completely different, it is a manual transmission that has a computerized clutch. You would never see an F1 race car utilizing a steptronic automatic transmission but they do use SMG. Whats the big difference? A manual transmission is much more efficient at converting horsepower at the crank to horsepower at the wheels. SMG gives you an added bonus in that when the computer is shifting for you it can actually shift faster than most humans can shift driving a manual transmission.

Here's a link to many of the different types of transmissions used in automobiles : Link

BTW- SMG has nothing to do with where the "shifters" are located. On the M3, the shifters are located on both the steering wheel, and the normal shifter.

 

[Mr.IncrediblyBored]

Originally posted by: minus1972
I'm not sure that it is the same as the steptronic, I thought that this was more like a computerized manual transmission where the steptronic was an automatic that you could shift when you wanted to.

Um, mechanically they are completely different.

LiQiCe has the right idea.

 

[dirtboy]

Originally posted by: Hammer
its the same as the steptronic but mounted on the steering column, not a heck of a lot of difference other than the coolness factor.

You are misinformed.

 

[thawolfman]

Originally posted by: FeathersMcGraw
You mean this isn't a Sarah Michelle Gellar thread?