Autoblog

Why, in two to three years Hyundai will put their 8 speed automatic to replace the ZF 6 speed auto.

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A dual-clutch transmission is faster, and has less power drag than a hydraulic automatic. A clutch system, even two wet clutches, is more direct than a hydraulic torque converter. And that would suit a sportier model, like the one illustrated.

An 8 speed hydraulic automatic will probably be even slower than a dual-clutch transmission that has two layshaft gear sets in constant mesh, instead of stacking all the gears on one layshaft.

Hydraulic automatics are fine for more softly tuned luxury-type vehicles...

But if it were to go to a sport sedan role, the dual-clutch gearbox would be a better performer.

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A dual clutch is faster how?
Less power drag, both have hydraulic pumps driven by the engine, and how does that relate to mileage when planetary automatic outclass double clutch transmissions in terms of ratio spread. (hopefully this will be 7.5:1)
The torque converter clutch can lock up in 1st gear, and you can remove the torque converter like MB did with the 7g-tronic.
If a double clutch transmission doesn't pre-select, it doesn't shift gears any quicker than automatics.
Automatics can be more 'direct' that double clutch transmissions. Say you are operating at 1500 and you need thrust, the torque converter can open and the engine can rev up to 2500rpm. Bam you've just doubled the available engine power to accelerate you. A double clutch would still be shifting or slowly accelerating from 1500rpm.

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A dual-clutch transmission is not hydraulically operated, there is no hydraulic pump, the way a hydraulic automatic does. The oil in the gearbox is only for part lubrication, not for pressurized controls. Dual clutch gearboxes are operated by electro-mechanical servos, and a computer controller, not a hydraulic circuit.

It is faster in the fact that a dual clutch gearbox only needs to transition between clutches to engage a higher OR a lower gear, much less than half a second. I have never driven an automatic transmission that the shifts were faster than I could think of them happening. Usually automatics don't shift when you want them to, and when they do shift, you can feel how slowly they work, usually at least half a second. I can shift a stick faster than most regular automatics. A dual-clutch computer controller is faster that almost any H-gate manual, and probably most sequential manual gearboxes.

All because the higher and lower gears adjacent to the current gear, are both in mesh and "on deck" so to speak, and can be selected and engaged almost instantly by alternating the two clutch engagements. Pre-selection. Pretty much all of the electro-mechanical automated gearboxes do it.

Faster in the fact that it doesn't have to spool up to "lock" a torque converter. The clutches are either engaged or not engaged at any engine speed, and the computer can shift faster than a human, or a hydraulic circuit. All the mechanical benefits of a manual gearbox, with as much or more convenience of an automated transmission.

Slipping the hydraulic torque converter doesn't add power to the system, it wastes more power shearing hydraulic fluid and creating heat, or creating pressure in a hydraulic circuit.

A double clutch gearbox would have shifted to the proper gear, and engaged the proper clutch, and been off and running in less than half a second, with all of the mechanical advantage it needs from the engine, well before a hydraulic torque converter would allow the engine to spin up and create the shearing forces in the fluid to start moving the transmission.

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What dual clutch are you refereing to? VW's new dry 7 speed

VW 6 speed has a crankshaft driven oil pump, does the clutches, does the actuating, does the cooling/lubricating
http://www.holt.us/tdi/vw_dsg_diagram_lg.jpg
Volvo also
http://www.motorauthority.com/wp-content/uploads/Volvo/odds/Volvo_Powershift_large.jpg
Porsche's new PDK, same with BMW's M-DCT, Audi's 7 speed S-tronic
Nissan GTR, Mitsu EVO
Bugatti Veyron too

Sure in the future the 'electrification' of double clutch transmission will be more pervasive,
http://getrag.de/en/231

I was referring to a situation where the driver of the double clutch was operating on the manumatic interface (sure BMW's manumatic interface will downshift if the downshift detent is pressed, by pushing the gas pedal ALL the way to the floor)

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I kinda like the grille. It does look klingon.

But it looks better than the blandness from Lexus and Toyota, and the oddities from Honda/Acura.

At least it is a bit distinctive.

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