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      01-08-2010, 04:52 AM   #1
akak1997
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Why CVT not popular?

I's in a discussion with a friend about CVT VS Auto VS DSC/DCT VS Manual and I just couldn't understand why it isn't being widely adapted or even replace automatic is most econ cars.

for those who don't know, CVT (continuously variable transmission) is a cheap and simple transmission that doesn't require a torque converter that sap power, and allows engine to run at max performance or best fuel economy rev range. Why isn't it become more available, especially when fuel price is on the rise?

Some people complains about the gearbox isn't as FUN as convention manual or auto, where you hear the engine revs up and down. But isn't this what Electric Cars gonna do as well? It will definitely need some getting use to the constant humming of the engine at one RPM... also when I's playing GT5 Prologue, the electric car is actually hard to drive fast coz there's no gear change, it's harder to get use to than I thought...

So what are you thoughts on this?
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      01-08-2010, 07:34 AM   #2
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Their behaviour and how they perform are unfamiliar to the general public which may explain why they haven't taken off that well, plus lack of torque capable though this will change with the introduction of the Torotrak IVT (improve CVT system).

Allison one of the biggest gearbox manufacturers are in the process of taking control of Torotrak.

http://www.greencarcongress.com/2009...n-transmi.html
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      01-08-2010, 08:29 AM   #3
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My previous car was an Altima 3.5SE with a CVT. It was indeed incredibly smooth and it was great to basically have an infinite number of gears so you could always get the exact amount of acceleration that you needed. It also had a manual mode which basically was set with certain gear ratios for the 'gears'.

That said, power delivery left something to be desired. If floored, you don't get that burst of power from a downshift but a gradual swell of power until youre at redline.

When I got the 135 I realized how much I missed the actual sound of the engine hitting redline and then dropping down for another go at it (Even if I do have an AT).
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      01-08-2010, 04:00 PM   #4
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footie posted some good info, CVTs by design are unable to handle real torque so their applications have been limited.
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      01-08-2010, 04:04 PM   #5
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Power handling, torque multiplication off the line that a torque converter provides, the incessant hum of hearing one RPM range all the time, lack of driver feedback... those are the reasons I can't stand driving a car with CVT.
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      01-08-2010, 04:24 PM   #6
akak1997
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My point is NOT replacing Auto gearbox in Performance oriented vehicles... for performance vehicles, manual or auto would still be the ideal choices. After all, nothing beats the Roam Roam from a powerful engine. On a side note, if this is what most performance car buyers are looking for, how the hell are they gonna market those Tesla? Barbus Engine soundtracks?

But I think for Econ cars like a Civic/Accord, Corolla/Camry... etc those can use a CVT or IVT right?
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      01-08-2010, 05:25 PM   #7
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cvt summed up, great idea, horrible to use, they work good on snowmobiles though

and mini coopers had them for a few years too
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      01-08-2010, 05:44 PM   #8
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Quote:
Originally Posted by MHP View Post
footie posted some good info, CVTs by design are unable to handle real torque so their applications have been limited.
Actually the Torotrak IVT system can cope with huge amounts of torque, more than you could possibly imagine. I honestly don't know how much it would be but it is vast.

CVT/IVT are very unusual in the way they perform, not something that appeals me but then again the performance they can be capable of produce is very appealing.
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      01-08-2010, 06:23 PM   #9
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Quote:
Originally Posted by akak1997 View Post
I's in a discussion with a friend about CVT VS Auto VS DSC/DCT VS Manual and I just couldn't understand why it isn't being widely adapted or even replace automatic is most econ cars.

for those who don't know, CVT (continuously variable transmission) is a Very Expensive and simple transmission that doesn't require a torque converter that sap power, and allows engine to run at max performance or best fuel economy rev range. Why isn't it become more available, especially when fuel price is on the rise?

Some people complains about the gearbox isn't as FUN as convention manual or auto, where you hear the engine revs up and down. But isn't this what Electric Cars gonna do as well? It will definitely need some getting use to the constant humming of the engine at one RPM... also when I's playing GT5 Prologue, the electric car is actually hard to drive fast coz there's no gear change, it's harder to get use to than I thought...

So what are you thoughts on this?

Fixed it for you...
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      01-08-2010, 07:05 PM   #10
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I think you will find that they don't have to be expensive, according to the info I have they can be supplied well below automatic prices and will prove to be more reliable, plus benefit on the economy of the car.
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      01-09-2010, 09:58 AM   #11
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My wife and I have a Sentra that pulls daily duties and it's equipped with a CVT transmission. I don't go racing around in it so we don't mind it at all. I think it's a great idea for the non-performance cars.
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