Liviu Marcus
A vehicle requires a transmission to connect the engine output to the wheels.
Internal combustion engines have a specific power band at certain RPMs, a transmission provides the driver with the option to adjust the speed of the car according to the scenario and stay in the power zone.
So before deciding which transmission you should opt for, you should identify what kind of transmissions are available. And how does each of them work?
Manual Transmission
A manual transmission is the simplest and oldest type of transmission used in road cars. In this transmission, contact is established with the engine with the help of a mechanical clutch. This type of clutch works by developing contact between two frictional plates connected to each component. A manual transmission when engaged has negligible power losses. It works by switching mechanical gears when the clutch is disengaged.
A manual transmission is cheap to manufacture and has simple components. A manual transmission provides sufficient feedback to the drivers and is preferred by car enthusiasts due to its fun-to-drive factor. But one needs enough knowledge and experience before power sliding on his manual. Although, it has become quite obsolete in modern cars due to its inability to launch a car properly equipped with a powerful engine. And due to the availability of better and easier transmissions. It has a steeper learning curve as compared to other transmissions.
Automatic / Torque Converters
An automatic transmission is much of an engineering wonder. In this type of transmission, the contact with the engine is developed by a torque converter. A torque converter uses a liquid as an intermediate to transfer the power. The engine is connected with the pump and the transmission side is connected with the turbine of the torque converter. The pump pushes the liquid at turbine blades to help it rotate. The torque conversion is done by a reactor, which is a one-way clutch with angled fins in between the pump and the turbine. At a slower speed, it multiplies the torque with the help of the reactor. And as it speeds up, the torque multiplication factor reduces.
Automatic transmission is relatively complex to manufacture. It is quite easy to drive and provides a smooth shift. But they are less efficient as compared to the rest due to the power losses. And the gear shift is quite slow. But they tend to be quite reliable and long-lasting and can be driven by a rookie driver.
Continuously Variable Transmission
A CVT transmission is much simpler and it uses pulleys and belts instead of mechanical gears. There are no gear shifts in this transmission. The torque is converted by varying the size of both the driving and the driven pulley.
A CVT transmission provides the smoothest torque conversion out of the rest. They are known to have an exceptional fuel economy. But it suffers through a lag when these transmissions are pushed hard, so they are not at all fun to drive.
Dual Clutch Transmission (DCT)
A DCT transmission can be imagined as two Manuals transmissions coupled together in a sophisticated manner. One of them contains the even gear and the other one contains the odd ones. Each of them comes with multi-plate clutches. At a particular time instant, the next gear is already preset and is ready to be engaged by the second clutch as the first one disengages.
A DCT is preferable in a sports-oriented performance car. It provides exceptionally quick, smooth gear changes. Its only drawback is its complexity in manufacturing, so comes with a higher cost. And they are less reliable than Simple automatic transmissions.
Sequential Transmission
An ST transmission is quite different than the other ones. They use a synchromesh or a dog box engagement system. In a synchromesh, arrangement gears can be changed in a short interval by depressing a clutch. Whereas, when coupled with a Dog box, this can be done without even depressing the clutch pedal. But gears can only be changed sequentially without any jumps and the Clutch has to be engaged to get in the first or reverse gear.
An ST transmission is easy to use, rugged, and offers quick gear shifts. It is mostly equipped in rally cars or drift builds. Whereas it suffers in providing reliability. It also results in a noisier transmission.
Auto Gear Shift
An AGS transmission is nothing more than a manual transmission coupled with a friction clutch controlled by a computer (ECU) instead of a human.
It offers an automatic experience at a relatively lower price due to the simplicity of components. It provides great fuel economy and is perfect for cheap Auto cars. But it suffers in providing smooth gear changes and handling quick starts.
Conclusion
So, in a nutshell, choosing the type of transmission depends on your needs and budget. If you want a fun-to-drive car, you can opt for a manual or a DCT if you have the budget for it. Whereas, if you want to enjoy smooth gear shifts, you can opt for an automatic or a CVT. To conclude, the choice of transmission largely depends on the preference of the driver as well as how deep his pockets are.
