The cars and bikes thread!

[Raza]

Wow... I will just say I like using a clutch with my foot. Even in traffic. I just like it. Oddly enough I hate the push button "manuals" more than just regular automatic... I mean if I can't do it myself then I'll just let the car do it. I don't really care about the micro seconds shaved off the time with the DCT. For me it's the engagement with my feet and hands that's part of the driving experience.

I'm the same way. I don't care if the automatic is better at it, it just doesn't feel the same.

[geoffbot]

Dual clutch "manuals" are automatic transmissions where, rather than a torque converter, two clutches are used to select gears. They are the ultimate evolution of the discrete gear automatic transmission.

Dual clutch transmissions were invented by Porsche in the late 1970s (the year 1975 comes to mind, but I'm not 100% sure), going into race cars in the mid-80s; what is currently on the market as the PDK (Porsche Doppelkupplungsgetriebe). The idea for dual clutch transmissions, though, came from a fellow named Adolphe Kegresse in 1939, but he never was able to get it to work. Volkswagen brought it to market first, with the 2003 Mark IV Golf R32 and the first in the United States was in the 2003 Audi TT 3.2 V6, under the trade name DSG for "direct shift gearbox".






It was revolutionary at the time; even though DCTs had been used in racing, they hadn't been viable in production cars for decades. And while single-clutch automatic transmissions had also already been on the market, in cars like the Ferrari 355, BMW M3, and Toyota MR-2 Spyder, they were all clunky, user-unfriendly, and basically hot garbage. By using two clutches to preselect the next gear, the DCT made shifting quicker and smoother than that of a single ACT and it was done with less driveline "slush" than a conventional automatic.

While CVTs have struggled with reliability (and that horrible droning noise they make), especially with higher horsepower applications, DCTs are better able to cope with high power now, rendering CVTs the transmission choice for low power economy cars, where fuel mileage is one of the top priorities. DCTs, in my opinion, are the best form of automatic transmission on the market. They do have some issues, however. The clutches are wear parts, for example. And most DCTs are closed units, so it's a hugely expensive job that requires removing the entire transmission to replace the clutches. At least that's how it is on my S4, from what I've read.

So is there a clutch pedal, and does the driver change gear?

[Seriously]

I didn't know what a dct was. Sounds like a clutchless manual? With o auto shift mode? Which of course is still a manual, but clutchless. Quite simple really.

Clutch PEDAL-LESS !!!!!

The clue is in the name - Dual clutch transmission

[geoffbot]

Yes yes yes obviously I mean the clutch pedal

[Raza]

So is there a clutch pedal, and does the driver change gear?

There is no clutch pedal. Both clutch packs are 100% automatic. The driver can put it into manual mode and shift using paddles, buttons, or through the gear knob, but the whole operation is computer controlled. Usually there’s a channel parallel to the PRND track that has a +/-. You push the shifter there to access manual mode.



Compare to a “Tiptronic” transmission, which is a conventional automatic with manual mode:


They both work functionally the same way to the end user, 100%. Slide the shifter over to +/-, and from there you can shift from the shifter, buttons, and/or paddles.

Many years ago, before Tiptronic became the norm for conventional automatics, there were other forms of manually shifted automatics. Here’s a quirky one, the Jaguar J-Gate.



Interestingly enough, decades ago, prior to Tiptronic, Porsche had a transmission called the Sportomatic, which was a manual that used a torque converter instead of a clutch. Funnily enough, even though the transmission could not shift on its own, Porsche still described it as an automatic.

To the end user, the main differences are that DCTs have less slack in the gear change process. It feels like a smoother automatic. All the physical differences are behind the curtain, so to speak.

[geoffbot]

Can't you do manual mode like that on all autos?

[Raza]

Can't you do manual mode like that on all autos?

As far as I know, yes. There may be some very low end models that still use old school PRNDL automatics, but I can’t recall seeing one in over a decade. Most low end cars use CVTs these days, and they often also feature a manual shifting mode using false gear ratios to mimic traditional transmissions.

[geoffbot]

So basically we know what an auto is and what a manual is. Got it.

[Raza]

So basically we know what an auto is and what a manual is. Got it.

Well, some of us seem to, at least.

[Samanator]

Dual clutch "manuals" are automatic transmissions where, rather than a torque converter, two clutches are used to select gears. They are the ultimate evolution of the discrete gear automatic transmission.

Dual clutch transmissions were invented by Porsche in the late 1970s (the year 1975 comes to mind, but I'm not 100% sure), going into race cars in the mid-80s; what is currently on the market as the PDK (Porsche Doppelkupplungsgetriebe). The idea for dual clutch transmissions, though, came from a fellow named Adolphe Kegresse in 1939, but he never was able to get it to work. Volkswagen brought it to market first, with the 2003 Mark IV Golf R32 and the first in the United States was in the 2003 Audi TT 3.2 V6, under the trade name DSG for "direct shift gearbox".






It was revolutionary at the time; even though DCTs had been used in racing, they hadn't been viable in production cars for decades. And while single-clutch automatic transmissions had also already been on the market, in cars like the Ferrari 355, BMW M3, and Toyota MR-2 Spyder, they were all clunky, user-unfriendly, and basically hot garbage. By using two clutches to preselect the next gear, the DCT made shifting quicker and smoother than that of a single ACT and it was done with less driveline "slush" than a conventional automatic.

While CVTs have struggled with reliability (and that horrible droning noise they make), especially with higher horsepower applications, DCTs are better able to cope with high power now, rendering CVTs the transmission choice for low power economy cars, where fuel mileage is one of the top priorities. DCTs, in my opinion, are the best form of automatic transmission on the market. They do have some issues, however. The clutches are wear parts, for example. And most DCTs are closed units, so it's a hugely expensive job that requires removing the entire transmission to replace the clutches. At least that's how it is on my S4, from what I've read.

I suggest you look up stickshift automatic in VW in the sixties. While these had H pattered and modern manuals with automatic clutches use sequential transmission ( like a motorcycle) kind of split in two to allow staging for speedy up or down. You could put them in high gear for auto mode. Pressure on the shift lever activated the clutch.

These are all manual trans with actual clutches electro mechanically controlled by the triggering in place of a clutch pedal/ shift lever( along with the fuel injection to simulate a double clutch/ heal and toe down shift on modern ones). As anyone who knows how to really ride a motorcycle the one thing your missing is sequential manual transmissions can be upshifted by placing pressure on the shifter and quickly cutting the throttle a bit quickly. No clutch required. If you raced you use to need to know how to do this without thinking. On performance racebikes starting in the 90’s they had an ignition cut switch on the shifter for the clutch less upshifts. You can’t do this on an H pattern trans. Dual clutch sequential gear boxes do this at lightning speed like the race bikes. This is why they are not automatics. They can’t be, they do clutchless full throttle upshifts.


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