Recent Topics
The audacity of auto part store prices
by Nayov
09/18/14 05:54 AM
F1 - 2014 Singapore Grand Prix
by gofast182
09/18/14 05:46 AM
Piston soak, alternatives to MMO?
by 19jacobob93
09/18/14 05:44 AM
Toyota Power Steering filter
by 01_celica_gt
09/18/14 04:28 AM
UOA Mailing Issues
by The Critic
09/18/14 02:56 AM
just curious
by coach477
09/18/14 02:51 AM
9/17-9/30 O'Reilly Super Saver Ad
by tenderloin
09/17/14 11:57 PM
'13 WRX: Mobil 1 ESP 5w30, 6,590 mi
by WRX12tt
09/17/14 11:54 PM
New Joe Bonomassa song and album
by Jimmy9190
09/17/14 11:14 PM
Used Oil Analysis in Taiwan suddenly very popular
by Apollo14
09/17/14 10:38 PM
Kellogg 331TV Cylinder Head
by Allan_G
09/17/14 10:31 PM
TSC Sale through Sept. 21st
by SilverC6
09/17/14 10:28 PM
Newest Members
waynesworld, Arcticfox, informme, Sherlock, Pokermatters
51330 Registered Users
Who's Online
46 registered (2010_FX4, aquariuscsm, 19jacobob93, ArtDart, Best F100, bds1984, 3 invisible), 847 Guests and 159 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
51330 Members
64 Forums
219404 Topics
3462290 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG

Page 2 of 5 < 1 2 3 4 5 >
Topic Options
#3425568 - 07/15/14 02:34 PM Re: CVT with shift sensation [Re: wing0]
Merkava_4 Offline


Registered: 01/30/07
Posts: 9164
Loc: Clovis, CA
I'm constantly monitoring which gear my car is in and when it shifts.

A CVT transmission that never shifts would drive me batty.

Top
#3425670 - 07/15/14 03:59 PM Re: CVT with shift sensation [Re: wing0]
Burt Offline


Registered: 01/08/09
Posts: 1033
Loc: texas
How about they put a fake stick and clutch pedal in too?
_________________________
2011 RX350 23k miles
1998 Windstar 201k miles and runs like new, well sort of.
Original owner, tranny and head gasket.

Top
#3425727 - 07/15/14 05:05 PM Re: CVT with shift sensation [Re: Burt]
KrisZ Offline


Registered: 12/23/06
Posts: 4259
Loc: Toronto, Canada
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. wink

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?


Edited by KrisZ (07/15/14 05:06 PM)
_________________________
2006 Mazda3 2.0 - 190,000 Km
2003 Ford Focus ZX5 2.0 Zetec - 160,000Km
Both on good old dino juice smile

Top
#3426023 - 07/15/14 09:58 PM Re: CVT with shift sensation [Re: KrisZ]
expat Offline


Registered: 05/12/09
Posts: 3796
Loc: Canada
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. wink

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 :-)


Edited by expat (07/15/14 10:02 PM)

Top
#3426080 - 07/15/14 11:41 PM Re: CVT with shift sensation [Re: wing0]
Shannow Online   content


Registered: 12/12/02
Posts: 26487
Loc: a prison island
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.

Top
#3426110 - 07/16/14 01:07 AM Re: CVT with shift sensation [Re: wing0]
Merkava_4 Offline


Registered: 01/30/07
Posts: 9164
Loc: Clovis, CA
I'd rather have an 8-speed car. The quickest cars in town are the 8-speed Infinities.

Top
#3426133 - 07/16/14 03:14 AM Re: CVT with shift sensation [Re: wing0]
gregoron Offline


Registered: 11/08/12
Posts: 488
Loc: Hawaii
This defeats the purpose of the CVT, which is programmed to keep the engine at its optimal power band. Each shift reduces the benefit. Either get an automatic or a stick if you want shift sensation.
_________________________
2000 VW Jetta GL 2.0, MT, 130k miles
Castrol Edge 0W-40 (5k miles OCI)
OEM Oil Filter (10k miles CI)

Top
#3426219 - 07/16/14 07:02 AM Re: CVT with shift sensation [Re: gregoron]
Hokiefyd Offline


Registered: 06/24/04
Posts: 11158
Loc: North Carolina
Originally Posted By: gregoron
Either get an automatic or a stick if you want shift sensation.


The point is that CVTs are increasingly replacing automatics altogether, and the customer has no choice but the CVT. The nice part about it is if they want the smooth feel of the CVT, they can have it. If they want the feel of a stepped transmission, they can have it. Flexibility is great.
_________________________
Cheers,
Jason

2008 Honda CR-V
2005 Acura MDX

Top
#3426236 - 07/16/14 07:21 AM Re: CVT with shift sensation [Re: wing0]
supton Online   content


Registered: 11/09/08
Posts: 4626
Loc: NH
How many shift points does it have? None going up, and six going down? 8 going up, and 9 going down? Not only that, but nothing says it has to be the same "ratio" at each point. It could decide to make a step this time and do a slide next time.

I think the rubber band effect would drive me nuts. Lately I've been wondering how people managed before lockup torque convertors. The two hundred rpm "rubber" effect I can hear when it's unlocked bugs me. I could imagine a 1,000rpm effect or more.

Then again, I prefer an engine to lug down and just torque its way out of something.

I am pretty sure I've asked this in the past, but never gotten a good answer: what would manual control of a CVT look like? On an automatic it's pretty easy: up/down manual selection of the fixed gear ratios. On a CVT, would it just be a slide switch? Seems like manually fixed ratios would be required on a CVT--otherwise, one could not have manual control.
_________________________
2004 VW Jetta Wagon, TDI, 5spd manual, 299kmile, his
2011 Toyota Camry, base, 6spd manual, 78k, hers
2010 Toyota Tundra double cab, 4.6L, auto, 88k

Top
#3426268 - 07/16/14 07:56 AM Re: CVT with shift sensation [Re: Hokiefyd]
d00df00d Offline


Registered: 10/20/05
Posts: 9145
Loc: PA
Originally Posted By: Hokiefyd
The point is that CVTs are increasingly replacing automatics altogether, and the customer has no choice but the CVT. The nice part about it is if they want the smooth feel of the CVT, they can have it. If they want the feel of a stepped transmission, they can have it. Flexibility is great.

Increased choice is a good thing only if the additional options are worthwhile. If I could only have toast for breakfast, adding eggs to the menu would be a meaningful increase in choice. Adding cyanide tablets wouldn't be.

"The feel of a stepped transmission" is three things:

1. Shift shock
2. Interruption in power delivery
3. The engine falling in and out of the optimal RPM range for whatever you're trying to do

In other words, all bad things.

I put up with all of those things in my car because it's manual, which means my toleration buys me a measure of control that I couldn't get otherwise. What is the argument for putting up with -- let alone WANTING -- those bad things in an automatic?

So far, all people have said is that stepless transmissions make the car feel broken. Everyone seems to understand that they only feel that way because they're used to "the feel of a stepped transmission." In other words, it's just habit. Why is nobody thinking "maybe I should look at it differently?"
_________________________
2011 Mazda RX-8 R3
Castrol GTX 5w-20

Top
#3426371 - 07/16/14 10:44 AM Re: CVT with shift sensation [Re: d00df00d]
Hokiefyd Offline


Registered: 06/24/04
Posts: 11158
Loc: North Carolina
Originally Posted By: d00df00d
"The feel of a stepped transmission" is three things:

1. Shift shock
2. Interruption in power delivery
3. The engine falling in and out of the optimal RPM range for whatever you're trying to do

In other words, all bad things.


I do agree that they made the package less efficient. If efficiency is your only metric, then sure, they're all "bad".

Life isn't always so black-and-white. I like to hear the engine rev up "through the gears". I like to feel the engine as it climbs through its power curve. I like to listen to the change in tone as it steadily increases in speed. I like to be able to load the engine down in a gear and not have it flare up in speed if I know that the load is temporary (like climbing a short hill or momentarily increasing my speed).

Variable ratios are boring to me. They further isolate the driver from the actions, from the feel, of the powertrain. I don't want that isolation. I want to feel it work. I want to hear it work. I actually LIKE that about stepped transmissions. I don't have manual transmissions in our vehicles for a few reasons, but it doesn't mean that I want to miss that feeling, that sensation, of a good engine/transmission combo going about its business.

I fully know that variable ratios are more efficient. I fully know that variable ratios enable better performance. That doesn't matter to me. If getting that last 1/10th of an MPG or that last 1 MPH in the 1320 means having to put up with a limp-feeling powertrain all the time, then I don't want it.

I don't have a problem with the mechanicals of a CVT. I like simple. I like easy. As a CVT owner, I would want to have a "D" mode where it would do its thing just like any other CVT. If I'm shuttling co-workers to lunch, or if my wife is driving the car, or if I'm just in the mood for quiet and smooth, "D" works. But I also want an "M" mode with paddle shifters so that I can work it up and down "through the gears" if I want to hear and feel the powertrain work. CVTs don't hold the engine for engine braking down hills or for switching back and forth on twisty roads. Sometimes that's what I want to do. Some may not want that, and that's cool; "D" is for them. Including an "M" mode costs very little and adds a huge degree of flexibility while still using the same equipment.
_________________________
Cheers,
Jason

2008 Honda CR-V
2005 Acura MDX

Top
#3426398 - 07/16/14 11:04 AM Re: CVT with shift sensation [Re: wing0]
stephen9666 Offline


Registered: 12/08/06
Posts: 2524
Loc: USA
I suspect they're doing this because of customers who don't know anything about the transmission or what they bought.

I'm guessing Nissan is trying to avoid dealer warranty trips and bad surveys (J.D. Power, etc) from owners who say "it's not working right, it won't shift."

EDIT- I just read the article and it appears this is probably the main thing driving this update.

Top
#3426494 - 07/16/14 12:56 PM Re: CVT with shift sensation [Re: wing0]
jrustles Offline


Registered: 02/24/13
Posts: 1977
Loc: Ontario, Canada
Bizarre. Employ a new technology just to defeat it.

About abnormal wear, I'd hope any self-respecting engineer would use some type of wear leveling logic in their pre-defined steps,ie alternating between say a 1.35 and a 1.28 (eg) 'virtual third gear' or whatever.
_________________________
"No matter how paranoid or conspiracy-minded you are, what the government is actually doing is worse than you imagine" W.Blum

Top
#3426505 - 07/16/14 01:06 PM Re: CVT with shift sensation [Re: wing0]
SteveSRT8 Offline


Registered: 10/10/08
Posts: 14750
Loc: Sunny Florida
C'mon guys. Shift shock? Whazzat? No modern automatic trans has any. Retarded timing and throttle reduction are precisely timed in many cars so you don't feel nuttin' unless you got your foot in it.

And the whole advantage of a slushbox, as well as the reason most of them are much quicker at the strip than their identical manual transmission variants, is there is NO interruption of the power delivery, none at all.

Moving cams has widened powerbands so far that many engines have a table flat torque curve, this pretty much means you are always in the 'optimal' rev range as well.

Next I am waiting to hear someone try again to tell us that CVT's have no wear in normal use!
_________________________
"In a democracy, dissent is an act of faith."
J. William Fulbright
Best ET-12.79 @ 111 mph
4340 pounds, Street tires
Just like we go to Publix

Top
#3427026 - 07/16/14 10:12 PM Re: CVT with shift sensation [Re: wing0]
wing0 Offline


Registered: 10/08/12
Posts: 113
Loc: Toronto, ON
I looked at some videos of cvt that goes through shifts. I noticed the rpm drops but not sure if it's a real or fake drop.

Does the transmission pause the movement of the belt for that split moment or it disconnect engine and transmission like a clutch?

Maybe these cvt 2.0 will require more frequent fluid changes?


Edited by wing0 (07/16/14 10:13 PM)

Top
Page 2 of 5 < 1 2 3 4 5 >