- Dec 3, 2001
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Which is going to be the transmission that will take over in the future? I'm pretty sure manual and automatics will eventually go away.
Originally posted by: TheEvil1
i dont know what either of thoes are.
i like standard its the only way to go
Originally posted by: atom
CVT. SMG may make shifting easier, but most people are lazy as hell and CVT is still easier to drive.
Originally posted by: bolido2000
Originally posted by: atom
CVT. SMG may make shifting easier, but most people are lazy as hell and CVT is still easier to drive.
Most SMG can shift automatically. Dunno what Toyota was thinking with the MR-2's SMG.
Originally posted by: KingNothing
CVTs are cool but they need to figure out how to make them withstand massive amounts of torque.
Assuming that doesn't happen, sequential (I assume you're talking about clutchless manuals ala BMW's SMG II) are the wave of the future.
Quick rundown:
CVT: Has no gears, adjusts the gear ratio by means of a belt (or chain, in Audi's case) and pulleys. All the efficiency of a manual and can accelerate a bit faster due to the fact that under hard acceleration it brings the RPMs to the power peak and leaves them there while it adjusts the gear ratios for acceleration.
Sequential:Clutchless manual means all the parts of a manual transmission - clutch pedal + hydraulics to operate clutch plates. BMW's SMG II can execute shifts in like 15 milliseconds, much faster than any human could. Also can do seamless downshifts and has an auto mode for when you don't want to hit the paddles to shift yourself.
Originally posted by: bolido2000
Originally posted by: KingNothing
CVTs are cool but they need to figure out how to make them withstand massive amounts of torque.
Assuming that doesn't happen, sequential (I assume you're talking about clutchless manuals ala BMW's SMG II) are the wave of the future.
Quick rundown:
CVT: Has no gears, adjusts the gear ratio by means of a belt (or chain, in Audi's case) and pulleys. All the efficiency of a manual and can accelerate a bit faster due to the fact that under hard acceleration it brings the RPMs to the power peak and leaves them there while it adjusts the gear ratios for acceleration.
Sequential:Clutchless manual means all the parts of a manual transmission - clutch pedal + hydraulics to operate clutch plates. BMW's SMG II can execute shifts in like 15 milliseconds, much faster than any human could. Also can do seamless downshifts and has an auto mode for when you don't want to hit the paddles to shift yourself.
There are already CVT that can withstand lots of torque in Japan. Nissan Gloria (or Cima) in Japan.
Sequential still operates with a clutch. The difference is that the driver doesn't control it. Seamless downshift is just revv matching which any driver can do, although it would be slower than a computer of course.
Originally posted by: KingNothing
Originally posted by: bolido2000
Originally posted by: KingNothing
CVTs are cool but they need to figure out how to make them withstand massive amounts of torque.
Assuming that doesn't happen, sequential (I assume you're talking about clutchless manuals ala BMW's SMG II) are the wave of the future.
Quick rundown:
CVT: Has no gears, adjusts the gear ratio by means of a belt (or chain, in Audi's case) and pulleys. All the efficiency of a manual and can accelerate a bit faster due to the fact that under hard acceleration it brings the RPMs to the power peak and leaves them there while it adjusts the gear ratios for acceleration.
Sequential:Clutchless manual means all the parts of a manual transmission - clutch pedal + hydraulics to operate clutch plates. BMW's SMG II can execute shifts in like 15 milliseconds, much faster than any human could. Also can do seamless downshifts and has an auto mode for when you don't want to hit the paddles to shift yourself.
There are already CVT that can withstand lots of torque in Japan. Nissan Gloria (or Cima) in Japan.
Sequential still operates with a clutch. The difference is that the driver doesn't control it. Seamless downshift is just revv matching which any driver can do, although it would be slower than a computer of course.
I never said sequential didn't have a clutch, only no clutch pedal. Sequentials can do a seamless downshift (by rev matching, yes) every time, and more perfectly than 98% of the drivers out there (myself included).
Link to the Gloria's CVT specs?
Originally posted by: bolido2000Ok. You mentioned clutchless manual so I thought you meant no clutch.
"If Audi?s Multitronic is an evolution of the conventional CVT, Nissan?s Extroid is obviously a revolution. Instead of using a belt or chain as the media for varying transmission ratio, it uses two pairs of rollers. As shown in the picture, the rollers link between the input disc (which connects the crankshaft) and output disc (which connects the driveshaft). By varying the angle of rollers, different transmission ratio can be obtained. For example, for "low" gearing ratio, the rollers meet the input disc near its inside diameter, but meet the output disc near its periphery; thus the output disc turns much slower than the input disc. The overall ratio range is 4.4:1.
Compare with belt or chain, the solid rollers can withstand much higher torque. Moreover, since the input and output disc are located at the same axis, it is able to be packaged in a longitudinal gearbox and drive the rear wheels. In fact, it is already driving the Cedric / Gloria in Japan, handling the massive 286 lbft of torque from the turbocharged VQ6.
The rollers are actuated by electro-hydraulic. However, the rollers are not directly contact with the input / output disc. A specially developed viscous oil provides the traction between them while reduce friction and wearing.
Like other modern CVTs, it also provides 6 artificial sequential ratios for more driver involvement.
Link to transmissions
Originally posted by: Bignate603
I think CVTs are more efficient in using an engine most efficiently but I think the torque problem holds it back.
Originally posted by: Jellomancer
If an SMG can only handle 280lbs... why not use two sets of pulleys instead of one?