California Clutch question

This month's Forza discussed the new dual clutch in the California and stated that the gears essentially instantaneously engage. Apparently, there are two clutches that are achieving this by working simulataneously on the two gears being transitioned.
Does that mean there would be little to no clutch wear if almost "instantaneous" swapping in and out?
Sorry in advance if this is an ignorant question.

 

Yes, but you still have to launch which is where much of the wear occurs in a Ferrari F1 style tranny. However, I read somewhere (I searched briefly but can't find the article) that the Cali uses 'Wet" (immersed in oil) clutches that should last the lifetime of the car. Or at least until the warranty runs out.
Dave

 

Finally Ferrari has caught up to my GTI's technology (Sorry, just needed that)

 

Yes, although I really am just B.S. ing here, I think VW uses dry clutches rather than the more advanced wet clutch like BMW.

 

AFAIK the DSG clutches are multi-piece (4) wet clutches. But I could be mistaking .... I read it somewhere.

EDIT: Just looked it up on wiki: Instead of a standard large dry single-plate clutch, each clutch pack is a collection of four small wet interleaved clutch plates (similar to a motorcycle wet multi-plate clutch).

EDIT AGAIN: Sorry ... we went OT ... back to the original topic.

 

As long as we are OT. I found this video on youtube and VW seems proud to have the first dry clutch DSG. But, although the Ferrari Cali may differ in that it has wet clutches, this is still an interesting video on the DSG concept.

http://www.youtube.com/watch?v=WVWP7TYhP0c&feature=relatedhttp://en.wikipedia.org/wiki/Twin-clutch_gearbox

dave

 

Ok ... one more OT:

That's the new 7-speed they are offering in the lower-hp models.(In Europe ... the 140hp TFSI, if I'm not mistaking) The 6-speed (GTI) still has the wet clutches.

 

VW-Chat?

Does anyone know about the California clutch technology? I find it interesting as it may find it's way into future Ferraris.
Thanks.

 

To get back on topic:

Essentially it will work the same way. You will have "two transmissions", on the one side you will have gears 1,3,5,7 and on the other side you'll have gears 2,4,6,R.
When the clutch engages on the one side, the other clutch will be ready to shift into the next higher gear, while accelerating. The clutches open/close almost instantaneously. (In my GTI it is 8ms - opposed to the Scuderia's 60ms with the new sequential gearbox. The California will be in the same "area")

When braking, the whole process is reversed. The downside of this transmission is, that unexpected gear changes can take quite a while, because the gears have to be reselected. (on my GTI, I'm sure Ferrari figured that one out).

I hope this can give you a general idea of a dual clutch gearbox.

This wikipedia article is rather informative http://en.wikipedia.org/wiki/Twin-clutch_gearbox

 

Not exactly, as when switching gears, the slip at the clutch that opens has to be positive, otherwise the torque would switch its sign (from positive to negative or vice versa). To achieve this, the engine rpm is automatically slightly raised. As slip means clutch wear, you can't get it down to zero.

 

Thanks guys, very helpful.
Neat technology!

 

I have a VW R32 with the DSG transmission. It does have a wet-clutch system, as discussed. The gear change is not instant, but the clutches act (one engaging while the other disengages) SIMULTANEOUSLY so that the perception of power delivery is that it is an "instant" shift. As I understand it, the California has a similar system. Interestingly, my '98 355F1, which has a much older generation of tech, reacts to pulling the paddle much more quickly than the VW. Therefore, my perception is the the F car has a "faster" shift than the VW.

John

 

They are wet clutches.

Seven speed gearbox.