458 vs Aventador transmission.

458 - nothing shifts as fast as a double clutch. You can hear how much slower the Lambo's box is in any number of videos out there.

 

Isn't the Aventador double clutch as well...?

But yes, the 458 has a faster, and smoother shift. The Aventador gives you a sore neck... which is nice sometimes

 

I believe it has the single clutch. At least that's what I read. I think the article mentioned that it saves weight in comparison to a DCT box.

 

The Aventador is a single clutch, its quick but not nearly as fast as the twin clutch in the 458.

 

Right. It's basically like an Formula 1 "seamless" gearbox, so smaller and lighter, but not as quick or smooth shifting as a dual-clutch. Though dual-clutch is banned in F1, it was not used much before it got banned because of the weight penalty.

Shift times must still be very good, despite there being some interruption of power transmission while single clutch disengages/re-engages. If it's good enough for F1...

Good write-up here:

http://www.caranddriver.com/news/car/10q4/lamborghini_murcielago_replacement_v12_powertrain_details-auto_shows

 

It has approximately a 40ms switch time. It's a very durable tranny and Lambo president said they would never use 1: turbo driven vehicles only normally aspirated 2: only single clutch as the weight of DSG is too heavy.

We shall see as time passes if this stays true or not.

 

He also said they would not sell rear wheel drive only cars as all wheel drive was a Lamborghini USP. He then went on to launch the LP550-2 Balboni followed by the regular LP550-2 which is now joined by the LP550-2 spyder

 

In Corsa mode at mid-high revs, they are the same speed. At low revs or outside of Corsa mode the 458 twin clutch is considerably faster.

The Lamborghini system is essentially a dual clutch system without the second clutch if that makes any sense. Both systems have the next gear selected before the first gear is disengaged, but the Lamborghini reuses the same clutch to engage the next gear, whereas the Ferrari has a separate clutch that's more closely matched to the anticipated engine speed prepared.

The jolt you feel in the shift on the Lamborghini is due to the clutch changing speeds and that energy being transferred to the wheels as the clutch engages the next gear. If Lamborghini replaces the clutch in a future model with one that is substantially lower mass, the gear shifts would become dramatically smoother.

* and yes ive driven both and this seems to be the case in both theory and practice. In the videos where the gear shifts on the Lamborghini sound slow, it isn't in Corsa.

 

The Gallardo replacement will surely have a DSG. The general view is that it is a superior technology.

 

I can't wait to see what they do with the Gallardo replacement...

And all upcoming Ferrari replacements as well! I want to see them now!

 

That's not quite correct for the Lambo gearbox. If both ratios are selected, the gearbox would effectively be locked up as the two ratios are mechanically linked on the same pair of shafts and without the "accommodation" provided by a pair of slipping clutches on separate shafts as in the DSG.

The difference between the Lambo and the classic gearbox is that different forks select adjacent ratios, so as one is disengaging, the next ratio is engaging – with some overlap, probably accommodated by the syncros – and conceivably while the clutch is disengaged so as to minimize wear on the syncros.

 

Is it just me or is that a fairly silly argument on the heavy Aventador? I realise that every little bit helps but an additional 40kgs or so would not have been measurable in performance times. It certainly doesn't seem to have hurt the lighter 458.


Onno

 

I agree. The real reason may have been space, not weight. Given free rein, the engineers would surely have preferred a DSG box. The "emotional" shift nonsense is just BS.

 

Perhaps to an extent budget was a consideration too.

 

Maybe, but on a $400k car? There surely must be room for a slimmer margin.

 

It could also be that because of the particular AWD system the Aventador uses it wasn't as easy or possible to adapt a DSG box that can handle over 500hp to the car. You have to remember that gearboxes have tolerances, as far as the amount of abuse they can take. Even though audi I believe uses a DSG system on some of their cars it might not be up to snuff yet. I'd predict the gallardo replacement to have some sort of DSG/PDK and then maybe a mid cycle refresh on the Aventador when they do a LP-398573987 versions.

 

The R8 replacement will have a double clutch transmissions. As a result, it is most probable that the Gallardo replacement will also have a DCT.

 

Could the reason be that there simply is no such DCT box available that could handle Aventador's power?

Aren't all DCT boxes subcontracted, for example the same box is in the 458 and the SLS (manufacturers can naturally fiddle with the software side of the box but not with the basic construction), and there is no other DCT equipped car with 700hp?

Lambo can't naturally admit that they would have preferred a DCT box, so they have to come up with some excuse...

 

ISM on the LP700 shifts at 50ms. What's the shift time on the 458? At 50ms, it's faster than F1 cars.

Those of you that had F1 and now own 458, do you miss the shift feel? My brother says that's the only thing he wishes the 458 does compared to his 360.

It would be interesting to see if Gallardo replacement gets the DSG for sure. I am going to say yes if R8 is slated for it. There is a lot of politics between Porsche, VW, Audi and Lambo on chassis. I haven't heard much on transmission choice.

 

What about the Veyron's gearbox? Too expensive?

 

That box was probably manufacturer's bespoke job for that car only...If I'm not mistaken I remember Clarkson saying that during the Veyron project the man responsible for the gearbox appeared to have become 20 years older in 2 years or something like this...

 

The DCT box used by Ferrari in the 458 & California, that is developed and produced by Getrag, is rated for a torque of 750 Nm. Hence the box could teoretically handle the Avantador engine's power.

There is though a weight penalty. DCT 120 kg, whereas the Avantador box weighs 80 kg

Graziano Trasmissioni in Italy has developed and is producing the Lamborghini box.

BTW Graziano used to be the subcontractor to Ferrari for gearboxes up to the F430.
The 430 box weighs 80 kg, so not all in the 458 is an improvement.....

 

Thank you for the information. A 40 kg/100 lb penalty is more than I would have guessed. There is an extra gear in the Getrag as well as the second clutch.

 

Yes 40 kg is significant. However modern supercars needs to be driverfriendly and near to maintenancefree, hence the DCT versus the single clutch.
And pls don't forget than even production of Ferraris is a matter of cost opimisation. The Getrag unit is produced in a decent annual volmer for various Mercedes, BMW and currently the 2 Ferrari models.