CVT with shift sensation

[wing0]

http://www.autoblog.com/2014/07/15/nissan-alters-all-cvt-act-less-like-stretched-rubberband/ Many new CVT out there have the shift sensation or shift logic built in to mimic automatics. I am just wondering, would this generate more wear and tear on the CVT in the long run?

 

[sasilverbullet]

Don't know, but my brand new 2014 Civic seems to have shift points.

 

[4wheeldog]

If the ECU is smart enough to vary the ratio shift points, it should not cause any odd wear. If it always shifts at the same ratio, I am thinking it will eventually "Notch" the cone.

 

[SwampSurvivor]

I can understand the concept of a CVT. But doesn't programming in gear ratios kind of defeat the purpose?

 

[4wheeldog]

Originally Posted By: Miller88

I can understand the concept of a CVT. But doesn't programming in gear ratios kind of defeat the purpose?

People are used to the feeling of torque from flywheel effect when the transmission shifts, so CVTs make it feel like there is less torque, and the "Rubber band effect" is the lack of that kick in the butt. It is a matter of perception, not an actual performance issue.

 

[leeharvey418]

Sooo.... Doesn't that kind of defeat the purpose of a CVT?

 

[901Memphis]

We don't need CVTs. 9 speed automatics can handle everything.

 

[d00df00d]

Originally Posted By: leeharvey418

Sooo.... Doesn't that kind of defeat the purpose of a CVT?

Yes. Completely. Discrete ratio programming on a CVT is one of the most blindingly stupid features I can think of. It blows my mind that people actually want it.

 

[JHZR2]

Originally Posted By: d00df00d

Originally Posted By: leeharvey418

Sooo.... Doesn't that kind of defeat the purpose of a CVT?

Yes. Completely. Discrete ratio programming on a CVT is one of the most blindingly stupid features I can think of. It blows my mind that people actually want it.

+1 Just plain stupid. For all the comments in the MT threads from the pro-AT folks, then technology moves on and we get this idiocy.

 

[badtlc]

shifting CVTs are have more of a slushbox feel than a torque converter based ATX. They are just terrible all around.

 

[d00df00d]

When you buy an automatic transmission and demand shift shock, you're saying you don't want to be involved in gear selection, but you do want to be jolted every time it happens. Think about what that means for a second. All the unsettling feedback, none of the control. It's tantamount to buying a machine the sole purpose of which is to poke you with a stick at random intervals while you're blindfolded.

 

[IndyIan]

Maybe they could do the BMW trick of aural engine enhancement, and use the sound system to simulate distinct ratios? I wonder as well, if there is some wear reduction on some part of the CVT by having many small steps in ratio change vs. a truly continous ratio change?

 

[gregk24]

I think it's a neat feature to have for those who like the feeling of shift points. I really could care less either way, as long as it's reliable then that's all that matters, CVTs are not performance transmissions to begin with.

 

[Hokiefyd]

Presuming that CVT reliability is good, and that they are perhaps lighter with fewer moving parts, etc, I think it's a great feature for those who want the sensation of gear changes. I like to feel the engine rev up through a gear, make a change, and then rev up again. It's part of how I'm programmed I guess. But I don't feel the need to make those gear changes myself. My wife can't drive one anyway, and has no desire to, so why not give consumers like me a choice in how a CVT drives and feels? The great thing is it's ALL orchestrated with computer programming. You can have it feel like a CVT if you want to. I can have it feel like a traditional automatic if I want to. No change in parts. More choice, more flexibility, more options...these are always good in my opinion.

 

[gregk24]

Originally Posted By: 4wheeldog

Originally Posted By: Miller88

I can understand the concept of a CVT. But doesn't programming in gear ratios kind of defeat the purpose?

People are used to the feeling of torque from flywheel effect when the transmission shifts, so CVTs make it feel like there is less torque, and the "Rubber band effect" is the lack of that kick in the butt. It is a matter of perception, not an actual performance issue.

What is the flywheel effect?

 

[Merkava_4]

I'm constantly monitoring which gear my car is in and when it shifts. A CVT transmission that never shifts would drive me batty.

 

[Burt]

How about they put a fake stick and clutch pedal in too?

 

[KrisZ]

Originally Posted By: Burt

How about they put a fake stick and clutch pedal in too?

I think a simulated stick and clutch pedal would sell well, fake not so much. Seriously though, I am also baffled why anyone would want to feel the shifts. After reading all the comments in the manual transmission thread how it's and "old" and "inferior" technology, why would anyone still be stuck with the "old" and "inferior" concept of fixed ratio gears?

 

[expat]

Originally Posted By: KrisZ

Originally Posted By: Burt

How about they put a fake stick and clutch pedal in too?

I think a simulated stick and clutch pedal would sell well, fake not so much. Seriously though, I am also baffled why anyone would want to feel the shifts. After reading all the comments in the manual transmission thread how it's and "old" and "inferior" technology, why would anyone still be stuck with the "old" and "inferior" concept of fixed ratio gears?

An active stick to control the transmission cones might be interesting. Kind of like having Hydrostatic drive. I think the Daff CVT of the 60's and 70's had the cones controlled by engine vacuum. I have driven them, they worked quite well. For maximum speed you had to back off on the throttle :-)

 

[Shannow]

Had a fair bit of seat time in a maxima early July, and honestly the programmed ratios in the cvt were a highlight. Only there in 'sport' mode, engine revved out and shifyed nicrly...plain auto was more prius like. Sports 'm' you had 6 ratios to work with on corners and engine braking. I liked it personally.