sequential manual transmission

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Hi,
I don't know hardly anything about cars yet (I'm learning). You know the Toyota MR2 Spyder, with the sequential manual transmission, I was just wondering if say, you're in 4th gear for example, and you're coming up to a red light. In a regular manual you'd push the clutch and the brake and stay in 4th gear until you stopped. But with the sequential, do you HAVE to downshift, or do you just push the brake and come to a stop. Sorry if this is a stupid question, I'm still learning.
Thanks
Paddy.
 
I hope it's not a stupid question, because I don't know either :) Actually I was unaware that Toyota actually put the sequential in the MR2, I read about it a while ago when they were talking about doing it, I didn't realize it made it to production though.

If the car has a clutch pedal, then you could just push that in when you come to a stop... I don't know how their system works though, I don't know if it even has a clutch pedal.
 
If it's the same transmission type as the one the Mazda6 comes with then nope, it down shifts automatically when you slow down.. and it also shifts up if you go to certain RPMs to prevent you from doing something bad :D
 
For ya'lls info (FYI :)) With a sequential manual transmission, so it acts exactly like a manual except for there is no clutch. I actually has two modes. One is an automatic mode (no it's not called that, but that's what it is), which acts like an automatic tranny. Then there's another mode (usually called sport) which allows you to select the gear manually, with some computer input for safety. For instance, Epic is right, but actually the computer will shift down to prevent you from doing something bad. It will also prevent shifting into an RPM that is bad for that gear, so you'll try to shift it (for instance, dropping into 4th from 5th at 5000+ RPM)(Stupid!) and nothing will happen, because if you normally shifted it, you'd break the engine, and that might be bad (duh):rolleyes: :D

Also, the features differ from car to car. Suggested searchings are the BMW SMG tranny for the new M3, and also tiptronic trannies from different manufacturers. Hope this helps.
 
tiptronic is a Porsche thing, and those are automatic transmissions, not semi auto ones like BMWs SMG or this Toyota one.

I don't know if any cars do it, but it would be possible to have a semi-automatic that still has a clutch pedal, or at least I can't think of any reasons why it wouldn't work.
 
OK, there's a lot of confusion going on here. I'll try to set some of it straight.

A sequential transmission, commonly used in racing and on some sports cars, is a specific thing, regardless of whether the car itself takes over some of the operation or not.

A sequential transmission is like a motorcycle transmission - push one way for upshift, push the other way for downshift. You must step through all the gears in turn - hence the name sequential. In a regular manual, you can downshift directly from, say, 5th to 3rd. In a sequential you MUST go 5>4>3. That's not to say you must let the clutch out in 4th, but you MUST pass through it.

Sequential manuals have a clutch for launches and full stops. In a race car the clutch is not typically used for shifts; the engine controller senses movement of the shift lever or paddles and interrupts fuel supply for a second during the shift so the driver doesn't need to lift. In a full-manual street car, you would typically use the clutch to shift, just like on a motorcycle.

In the case of the MR-2, there is a computer-contolled manual/automatic clutch. I believe it can be driven fully manually, but there is also a mode where the PCM (powertrain control module, or computer) will operate the clutch for you, feathering the launches, putting it in for stops, and even blipping the throttle for a rev-match downshift. This is unrelated to the fact that the MR-2 also has a sequential gearbox, though. It's merely a robot-actuated clutch.
 
Yea, the MR2's transmission is really cool. Much more responsive than the semi-autos in certain sedans.
 
Wait, isnt this called the Sportmatic tranny? Ive seen it called that on the Mazda 6, Pontiac Gran Prix, Lexus IS300, and some others.
 
OK, there's a lot of confusion going on here. I'll try to set some of it straight.

A sequential transmission, commonly used in racing and on some sports cars, is a specific thing, regardless of whether the car itself takes over some of the operation or not.

A sequential transmission is like a motorcycle transmission - push one way for upshift, push the other way for downshift. You must step through all the gears in turn - hence the name sequential. In a regular manual, you can downshift directly from, say, 5th to 3rd. In a sequential you MUST go 5>4>3. That's not to say you must let the clutch out in 4th, but you MUST pass through it.

Sequential manuals have a clutch for launches and full stops. In a race car the clutch is not typically used for shifts; the engine controller senses movement of the shift lever or paddles and interrupts fuel supply for a second during the shift so the driver doesn't need to lift. In a full-manual street car, you would typically use the clutch to shift, just like on a motorcycle.

In the case of the MR-2, there is a computer-contolled manual/automatic clutch. I believe it can be driven fully manually, but there is also a mode where the PCM (powertrain control module, or computer) will operate the clutch for you, feathering the launches, putting it in for stops, and even blipping the throttle for a rev-match downshift. This is unrelated to the fact that the MR-2 also has a sequential gearbox, though. It's merely a robot-actuated clutch.

Yeah thats right, mybad :lol: what the hell was I somkin.... for those that still dont get it, think "Tap shift" on most arcade racing machines
 
Originally posted by retsmah
tiptronic is a Porsche thing, and those are automatic transmissions,

I think I was wrong on that, looks like it's used in Audis too... I think tiptronic is actually german for "transmission for [watch your mouth]"

At this point the only cars with semi automatic transmissions are the MR2, the BMW M3, and some Ferraris and Aston Martins right?
 
Right, these cars are not Tiptronic. There is no automatic mode if I'm correct.
 
Originally posted by retsmah
I think I was wrong on that, looks like it's used in Audis too... I think tiptronic is actually german for "transmission for [watch your mouth]"

At this point the only cars with semi automatic transmissions are the MR2, the BMW M3, and some Ferraris and Aston Martins right?

Alfa Romeo also have a 'Selectronic' manual in the 156 - same deal, push button operated manual transmission with electronic clutch.

The M-Benz A-Class has an electronically operated clutch with a traditional H pattern manual shift - just no clutch pedal!
 
Originally posted by vat_man

The M-Benz A-Class has an electronically operated clutch with a traditional H pattern manual shift - just no clutch pedal!

That's... weird, I'd like to try driving one of those :)
 
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