10 speed auto gearbox from Hyundai

[TWPC]

The next step:
http://wot.motortrend.com/we-hear-hyundai-and-kia-...

I realise this is a much discussed topic but I suppose that if you can constantly increase the number of gears without compromising weight and reliability then why not? With the right software I suppose you can harness it for both economy AND power/speed.
Is there any limit to the number of gears you can effectively control with flappy paddles, or would you just leave a 10 speed auto in D all the time?
It does seem extraordinary though and in the right car surely suggests the development of an engine that only works in an incredibly narrow rev band. Dull for us...

[RossP]

If manufacturers keep increasing the gears, surely a more refined CVT gearbox is going to benefit narrow rev-range engines?

[GroundEffect]

RossP said:

If manufacturers keep increasing the gears, surely a more refined CVT gearbox is going to benefit narrow rev-range engines?

CVTs are not very efficient with large torques.

[TWPC]

I get the impression that CVTs are less versatile too, i.e. reviewers seem to like the 'sport' modes available on conventional autos whereas I have never read a review of a CVT successfully delivering the same experience.

[TheTurbonator]

Seems to work for the people racing in the Fast and Furious films. They're always finding another gear, which gives them a burst of speed

[Ozzie Osmond]

After several decades of development I think it's safe to say the CVT is now dead.

Multi-geared auto's can be built to incredibly fine margins with modern materials and fancy electronic torque control of the engine. These multi-speeders are like a swiss watch inside yet mind-bogglingly reliable.

[TWPC]

Ozzie, I generally agree but have now found this review of a new Lexus which has a CVT and sounds moderately sporty: http://www.autocar.co.uk/car-review/lexus/gs/first...

Sticking with manual myself (and the wife is even more of a militant on that point than me).

[J4CKO]

Pah, my Trek 8000 has ten speeds already.

[DonkeyApple]

TWPC said:

The next step:
http://wot.motortrend.com/we-hear-hyundai-and-kia-...

I realise this is a much discussed topic but I suppose that if you can constantly increase the number of gears without compromising weight and reliability then why not? With the right software I suppose you can harness it for both economy AND power/speed.
Is there any limit to the number of gears you can effectively control with flappy paddles, or would you just leave a 10 speed auto in D all the time?
It does seem extraordinary though and in the right car surely suggests the development of an engine that only works in an incredibly narrow rev band. Dull for us...

There will be a finite number but a high number of gears suits a cooking engine that is specifically built to operate in a narrow power band and deliver the best 'modern' economy. But you wouldn't ever bother changing gear manually. It is a gearbox essentially for drones.

For a driver's car there really isn't much need for more than 5 gears, maybe 6 if you have a very high top speed but fundamentally each extra gear diminishes the 'drive'.

[Ozzie Osmond]

TWPC said:

Ozzie, I generally agree but have now found this review of a new Lexus which has a CVT and sounds moderately sporty: http://www.autocar.co.uk/car-review/lexus/gs/first...

Interesting, although I note it's a hybrid. Is only some of the torque being applied through the CVT with the remainder provided directly to the wheels by an electric motors? Or is everyhting going through the CVT? I can't tell from the write-up but would guess the former.

[jagfan2]

Ozzie Osmond said:

Interesting, although I note it's a hybrid. Is only some of the torque being applied through the CVT with the remainder provided directly to the wheels by an electric motors? Or is everything going through the CVT? I can't tell from the write-up but would guess the former.

Its not that simple, its an electric parallel CVT

http://en.wikipedia.org/wiki/Lexus_Hybrid_Drive

It helps if you have a degree in engineering to understand the drive modes as it uses multiple planetary gearsets

[Four Litre]

The ISF has 8 gears. At first I thought this was 2 too many, however as a cruising gear it gets the revs right down and helps with the MPG. I usually use 1-6 around town and 7/8 Motorway.

Shirely 10 though is getting a bit silly!

[thinfourth2]

Thats more then my Unimog

[AnotherClarkey]

jagfan2 said:

Ozzie Osmond said:

Interesting, although I note it's a hybrid. Is only some of the torque being applied through the CVT with the remainder provided directly to the wheels by an electric motors? Or is everything going through the CVT? I can't tell from the write-up but would guess the former.

Its not that simple, its an electric parallel CVT

http://en.wikipedia.org/wiki/Lexus_Hybrid_Drive

It helps if you have a degree in engineering to understand the drive modes as it uses multiple planetary gearsets

Hard to understand maybe but mechanically simple and reliable. Seems far less complex in mechanical and control terms than a modern automatic transmission, especially one with 10 speeds

[Ozzie Osmond]

jagfan2 said:

Its not that simple, its an electric parallel CVT

OK, I've got it now. It's not really a CVT as we've traditionally understood them but Toyota calls it e-CVT as a description of what it does.

Excellent illustration on this link. Drag the sliders and watch it work!

http://eahart.com/prius/psd/

[gtrstill]

Four Litre said:

The ISF has 8 gears. At first I thought this was 2 too many, however as a cruising gear it gets the revs right down and helps with the MPG. I usually use 1-6 around town and 7/8 Motorway.

Shirely 10 though is getting a bit silly!

I totally agree with this post and the one about 5/6 gears. Having driven the ISF now for two weeks I can say that first is only really helpful for pulling away smoothly and 7th and 8th for cruising.

Gears which I would say add to the driving experience of the ISF start at 2 and end at 5. On a track I would be amazed if you ever got to 7 and would only use 6 on a long straight.

4 gears! who needs more

[clonmult]

10? I'm going to wait until they've given us 11 ... turn it up to 11!