CVT better than manual?

[jayjack]

alright i was kinda thinking since CVT's varry the gear ratio so much im sure they can keep you at your peek horse power or torque almost constantly so couldn't they keep you in your power band much more effictively than a manual could, thus making them faster? or is there something i don't know about them that makes them blatently worse? and if they are better why aren't they in higher use?

[curtis73]

Well, better is a subjective thing. CVTs are not very strong yet, so they can't really be used in anything but lower power applications. They are great in economy cars, and have started being used in some light performance cars. They are nice because they keep you at an RPM that is best for your situation, and they don't waste time shifting or slipping like a manual or automatic, but they have their shortcomings. For instance, in a light economy car it makes sense. When you put your foot to the floor, the transmission keeps the RPMs at or near the HP peak for best acceleration. Then at cruise it keeps RPMs low for mileage. But in a HD towing application, you would want it to select a point where torque is also high.

Its simply another transmission. It has its place, but its not the best in every application.

[MagicRat]

I noticed that Ford has dropped the CVT transmission option for their 2008 mid sized sedan. No reason was given, but IMO this is not a good sign, perhaps due to lack of durability, lack of consumer interest, cost of manufacture or a combination of reasons.

IMO a CVT transmission needs to be programmable in order to be truly effective.
I have read that some feel CVT's simply are set up to rev too high (excess noise, vibration and fuel use) at part throttle applications.
It would be nice if the driver could simply 'dial - in' how agressively they want the engine to rev up during acceleration and at cruising speed.

This would be, IMO, consistent with the manual gear selection feature that most automatic transmissions still retain.

[jayjack]

i kinda think with alot of work CVT's could be really effective. i mean if they were stronger, more reliable, and had much better programming, they might be sweet little tranys. it might be an undertaking but in sure like GM or some body could put many million into some sick CVT to go with one some of there sweet engines.