WickedStook

what does CVT mean

David

Continous variable transmission.

I don't understand why the Japanese always soften their performance cars when they bring it over here. It doesn't matter which manufacturer but they all do it. Don't they understand that even though these performance cars would serve a niche market, there is enough people here to justify all the hoops they have to jump through.

By the way, I don't like the G35 -- bring over the real thing.

DouglaS2000

Ummm, not to flame here but a CVT transmission is a gearless automatic so it doesn't make sense that it has 8 speeds or any speed for that matter. CVT stands for Continuously Variable Transmission and it is belt driven. It's been around on the Civic HX for quite a while and it is also offered on the Insight and Toyota Prius.

Although there are different variations on the CVT theme, most passenger cars use a similar setup. Essentially, a CVT transmission operates by varying the working diameters of the two main pulleys in the transmission.

The pulleys have V-shaped grooves in which the connecting belt rides. One side of the pulley is fixed; the other side is moveable, actuated by a hydraulic cylinder. When actuated, the cylinder can increase or reduce the amount of space between the two sides of the pulley. This allows the belt to ride lower or higher along the walls of the pulley, depending on driving conditions, thereby changing the gear ratio. If you think about it, the action is similar to the way a mountain bike shifts gears, by "derailing" the chain from one sprocket to the next

S2KALI

Confused here, if Audi can have a 6 "speed" tiptronic feature coupled with its CVT, why can't Nissan offer a 8 "speed" F1-style sequential shift to go with its CVT? Essentially, F1 paddles and a tiptronic are the same. Both electronically actuate a gear change or (in this case) a step change.

Da Hapa

My 2 cents.

The Japanese manufacturers typicaly don't bring their cutting edge cars to the US for a number of reasons. First and foremost is that they use the home market as their test bed, so to speak. Any bugs with new products are worked out in Japan before export. Other reasons include US safety, smog, and build legislation which often times preclude us from getting the same cars that Japanese have. For example, the US didn't get the manumatic tranny for the Lexus GS430 this year. The same tranny was offered in the prior GS400 but because of emissions testing problems, we got screwed. Many more examples exist, including problems getting the current Mitsubishi EVO to comply with federal safety and smog rules.

As to the question of the CVT. Both posters above are correct. A true CVT has an infinite amount of gear ratios. However, as in the case of the 2002 A4 with CVT, you can "pre-program" certain gear ratios so allow for such items as the Audi tiptronic tranny. Simply put, the new A4 (and I would assume the Nissan mentioned earlier) has the option of using the true CVT mode or it can be shifted quasi-manually by relying on some form of manumatic tranny with some range of pre-set gear ratios.

AVXs2000

Da Hapa explains very clear

sorry I should mention the meaning of "gear" in CVT earlier.
there are no gear in the CVT or there are infinity gears in CVT.
the CVT can be program into infinity "gear" (100 speeds, 1000 speeds if someone actually needs)
but the "gear" is only a computer program that simulate different gear ratio.

there are already CVT with 7 "speed" on many cars like Subaru Vivio in Hong Kong, and the CVT is pretty good from what I read from the press of Hong Kong.

and for what I knew, the changing "gear" time of GT350-8 takes 200ms, and should be quicker than many Sequential manual except the Siemens SMG2 and Magnetti Marelli F1(only the Ferrari version is faster than Nissan CVT).

just something I read.