CVT Transmission talk

[Delirious]

i made a post about it in GT4 forums concerning the prius...didnt really get many answers

i remember the subaru jutsy had one back in early 90s or 5 speed manual, and i believe it was a 1.3 liter, and i also remember that you could only use the CVT with a 1.3 liter engine or below...

so how on earth can nissan murano and other bigger cars use it? what did i miss?

also, how exactly does CVT perform concerning driving and acceleration and etc.?

and, if it's continuously variable, why not use it for major racing purposes? wouldnt it be great for acceleration and still have a high top speed?

if i missed anything important/worthwhile mentioning concerning this topic, go ahead and add it and feel free to add your 2 cents in

 

[Emohawk]

Wow, I didn't know CVTs were availible in production cars in the early 90s.
There are a variety of ways to achive a CVT, but all of them involve some kind of viscous coupling (if I have my terminology straight). This limits the amount of torque that can be transmitted through them without causing slippage.
The reason larger cars (larger engines, more precisely) can use it now is that technology has advanced and CVTs can now hold higher levels of torque. Still not a whole lot though, which is why they're not used in racing.
I suppose they could give a significant advantage in low-power spec racing (ie; formula Ford and formula V), but CVTs are't nearly grassroots enough for that to happen yet (even if they were legal, which they probably aren't).

Just so this post contains absolutly everything I know about CVTs:
1)here's an article explaining them
2) The Honda Helix scooter uses one. This allows the engine to be tuned to produce more power then it normally would, but only in the very small rev range the CVT requires it to operate in. The muffler can also be tuned to very effectivly block out the noise at that specific narrow RPM band, and it is.
As a result, the Helix is very quiet and surprisingly fast, considering it's size and engine displacement.

 

[1X83Z]

i remember the subaru jutsy had one back in early 90s or 5 speed manual, and i believe it was a 1.3 liter, and i also remember that you could only use the CVT with a 1.3 liter engine or below...

Emohawk I think covered the rest of this, but I can handle this one. While most people associate CVT with Honda, Honda was not the first manufacturer to use the technology. In 1989, the Subaru Justy did indeed become the first vehicle on the market with a continuously-variable automatic transmission; it was mated to a 73-horsepower 1.2-liter SOHC I-3. The transmission was cancelled in 1993 (the entire Justy was cancelled the following year, 1994), though from 1989 to 1993 it turned a pretty bad car into a fairly interesting one.

Reviews were typically positive of the CVT's ability to move the car better than a conventional automatic and get better fuel returns than one, too. The next CVT debuted in 1996, available on the Honda Civic HX. Currently, Audi, Ford, Honda, Mercury, Mini, Nissan, Saturn, and Toyota (more?) use CVT transmissions.

 

[mr_pushrod]

My uncle had a CVT equipped Fiat Punto and it was eeirly smooth. Would work very well on a big luxury car I think although the constant drone from the engine does become tiresome under acceleration. Also on the Fiat there was a manual mode with 6 'gears' which struck me as one of the dumbest features I'd ever seen.