Some prospective buyers of the all-new 2014 Honda City may have wondered why there is a mention of a 'torque converter' in the City's specifications list, when the model is equipped with a continuously variable transmission (CVT). This can be rather confusing especially to buyers who have read many other articles saying that the previous model's five-speed torque converter automatic has been replaced with a CVT.
Thirty years ago, car buyers only had to decide between two main types of transmissions - a manual and an automatic. The manual transmission uses a single-plate dry clutch while the automatic uses a torque converter.
Yes, even in the '70s, there were a small number of manufacturers who also offered early generations of CVTs and automated manual transmissions (AMT) but these were outliers rather than the norm.
These days however, automatic technology has gotten a lot more complicated. Many car manufacturers and transmission specialists are employing multiple means to marry the advantages of both a manual and an automatic, resulting in the proliferation of CVTs, AMTs and dual-clutch transmissions (DCTs) equipped models entering the mainstream.
In the past, CVTs were generally understood as a very energy efficient type of transmission that employs a set of variable diameter pulleys to produce an infinite combination of gear ratios.
Some drivers who were used to a conventional automatic complained that during hard acceleration, they disliked the experience of a vehicle increasing in speed without proportionate increase in engine speed, an intentional characteristic of CVTs to achieve optimum fuel efficiency.
To mitigate this, some CVT units have an 'S' mode that is pre-programmed with a finite number of virtual ratios, usually seven, to simulate the shift-shock of a conventional automatic transmission as it shifts from one gear to another.
There were also issues surrounding the durability of CVTs when subjected to sustained high speeds and frequent hard accelerations. The second-generation Honda City had issues with premature failure of its CVT but curiously, the problem is only apparent in Malaysia.
The City owners in Thailand, Indonesia and even India, which uses the same transmission manufactured in the same plant did not experience any problems.
Privately, a Honda engineer I spoke to at last year's Tokyo Motor Show acknowledged that the driving habits of Malaysian drivers can be quite stressful to a vehicle.
"Although the national speed limit is only 110 km/h, we noted that drivers in Malaysia usually drive a lot faster than drivers in other countries. The wide network of highways also means that the high speeds are sustained for quite long," said the chief engineer from Honda R&D Co., Ltd. in Japan.
He went on to explain that learning from their past experience, Honda models sold in Malaysia are adapted with additional or higher grade components to cope with the driving conditions. The all-new Accord for example, features a different European-market specification brake system that is not adopted by other ASEAN countries.
This is not surprising, as we know that Nissan also performs similar adaptations for its Malaysian market models. The Teana for example, has an additional transmission oil-cooler that is not fitted in Teanas sold in other ASEAN countries.
With this all-new in-house developed Earth Dreams series CVT, Honda is confident that problems associated with its earlier generation CVT have been banished for good.
"We are confident that the problems which occurred with the previous CVT will not happen again," said Large Project Leader Kazunori Watanabe during the launch of the all-new City last Thursday.
Watanabe's confidence lies with an all-new CVT that incorporates a torque converter instead of a pair of start-up clutches like in the previous CVT.
"The main difference compared to the previous CVT is that we have introduced a torque convertor into the CVT," he said.
Incorporating torque converters into a CVT is not new. Many manufacturers these days have already incorporated them in their existing models but choose not to highlight it to avoid confusing their buyers. Even within Honda, CVTs with torque converters were already being used in the second generation 2007 Honda Jazz and the previous generation 2003 Honda Odyssey.
This time around, Honda may want to highlight the point to assure potential buyers of the transmission's durability.
From this point onwards, it may be better if we refer to conventional automatics as stepped automatics rather than torque converters.
Watanabe explained that with the introduction of a torque converter within the CVT, the transmission's durability is now a lot better than before.
Another advantage of incorporating the torque converter is that the Honda City's CVT now feels more responsive. Compared to early generation CVTs, this unit does not suffer from the 'rubber-band effect' that characterised earlier units.
The torque converter provides for better performance during start-up and acceleration, thus delivering the type of response similar to conventional stepped automatics, except that the CVT is a lot more fuel efficient, at least 10 percent more.
The transmission also intelligently detects if strong acceleration is required and holds onto a higher gear ratio longer to maintain higher engine speeds even when a driver lifts off the throttle. Honda says this allows the car to react to the driver’s modulation of the accelerator pedal with power and sensitivity, for sportier driving performance.
This explains the good driving experience we had when we test drove the all-new City on twisty countryside roads. The CVT felt responsive enough and acceleration was linear.
You may also want to read: