Its certain;y true that a CVT when properly controlled adjusted has the advantage on discrete gear ratios, as in theory the ECU should keep the engine at its peak efficiency conditions and adjust the CVT.
Historically however CVT's have failed to be attractive to the driving public, and I suspect it's been the apparent disconnection between engine speed and vehicle speed, often the engines have been running faster than drivers expect and this seems unnatural, so much so that some manufacturers actually programmed to transmissions to simulate shifting with fixed ratio's!
One of the major pressures on manufacturers has been to improve fuel efficiencies, CVT's theoretically offer an infinite number of gear ratios which does in theory mean the engine can be kept operating in its most efficient power band, but the public's distaste of the way CVT's operates forced manufacturers to look at increasing the numbers of fixed gear ratio's, which is why we often see cars with 6 or more forward gear ratio's ( I think one manufacturer introduced a 9 gear ratio box in some models) These keep the engines operating speed closer to optimum, but the down side is there are more gear changes to be made, so many of these boxes are semi or full automatics and the advent of the dual clutch systems like the VW DSG allow for some very slick systems where shifts are very fast and almost seamless.
DSG's and other similar boxes are proving to offer strong performance, but with so many additional parts in the boxes there are natural concerns about long term reliability. As previously discussed in the thread DSG's especially in their latest form are proving to quite reliable, even on high performance vehicles. so it seems that dual clutch boxes are becoming far more popular.
Where does this leave the CVT? It seem that some (usually smaller niche market) manufactures are trying to develop CVT's But until their reliability is seen to have been massively improved, it's unlikely they will unseat the fixed gear boxes with high numbers of ratio's. Also with the political pressure to move away from ICE, Manufacturers will be reluctant to invest in CVT's when there is a lot of knowledge and prior experience with fixed ratio boxes.
Historically however CVT's have failed to be attractive to the driving public, and I suspect it's been the apparent disconnection between engine speed and vehicle speed, often the engines have been running faster than drivers expect and this seems unnatural, so much so that some manufacturers actually programmed to transmissions to simulate shifting with fixed ratio's!
One of the major pressures on manufacturers has been to improve fuel efficiencies, CVT's theoretically offer an infinite number of gear ratios which does in theory mean the engine can be kept operating in its most efficient power band, but the public's distaste of the way CVT's operates forced manufacturers to look at increasing the numbers of fixed gear ratio's, which is why we often see cars with 6 or more forward gear ratio's ( I think one manufacturer introduced a 9 gear ratio box in some models) These keep the engines operating speed closer to optimum, but the down side is there are more gear changes to be made, so many of these boxes are semi or full automatics and the advent of the dual clutch systems like the VW DSG allow for some very slick systems where shifts are very fast and almost seamless.
DSG's and other similar boxes are proving to offer strong performance, but with so many additional parts in the boxes there are natural concerns about long term reliability. As previously discussed in the thread DSG's especially in their latest form are proving to quite reliable, even on high performance vehicles. so it seems that dual clutch boxes are becoming far more popular.
Where does this leave the CVT? It seem that some (usually smaller niche market) manufactures are trying to develop CVT's But until their reliability is seen to have been massively improved, it's unlikely they will unseat the fixed gear boxes with high numbers of ratio's. Also with the political pressure to move away from ICE, Manufacturers will be reluctant to invest in CVT's when there is a lot of knowledge and prior experience with fixed ratio boxes.
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