Alfa Romeo will debut Fiat Powertrain's innovative new "TCT" gearbox, the latest automatic dual dry clutch 6-speed transmission that is part of the modern family of 6-speed gearboxes (C635), on the MiTo in Geneva next week.

Alfa Romeo will debut Fiat Powertrain's innovative new "TCT" gearbox, the latest automatic dual dry clutch 6-speed transmission, coupled to the Start&Stop device, on the MiTo on the occasion of the 80th Geneva Motor Show next week.

Developed and produced by FPT, Fiat Powertrain Technologies, this new device is part of a modern family of 6-speed gearboxes (C635) that was launched - in the mechanical version - on the 170 HP MiTo 1.4 MultiAir Turbo petrol. Now it's the turn of the “Alfa TCT” teamed with MultiAir engines with Start&Stop system fitted as standard: indeed, the Alfa Romeo MiTo is the first car on the market to combine these three innovative technologies. Available from next spring, visitors to the show will be able to admire a 135 HP MiTo 1.4 MultiAir Turbo petrol with “Alfa TCT” and gear levers incorporated into the steering wheel (optional).

The new device, conceptually, consists of two gearboxes in parallel, each with its own clutch, which allows the selection and engagement of the subsequent gear while the previous one is still engaged. The gear is therefore changed with a simple gradual switch of the corresponding clutches, guaranteeing continuous torque delivery and therefore traction. The result is a driving comfort and sporty feeling well above those offered by conventional automatic transmissions (with torque converter), as proven by greater speed of gear shift, the possibility of selecting between manual or automatic mode and a near-zero power loss during the gear change. In addition, the purchasing, servicing and running costs are limited, while fuel consumption is reduced, thanks also to the implementation of the Start&Stop system, up to 10% less than a traditional automatic hydraulic transmission with torque converter.

Specifically, the “Alfa TCT” features the largest number of interactions with the vehicle's systems available on the market. Indeed, its operation interacts with the steering wheel, the brake and accelerator controls, the Alfa DNA selector, the Start&Stop system, the ABS, the engine and the inclinometer (slope detector to engage the Hill Holder and disable Start&Stop on activation).

Other peculiar features of the new “Alfa TCT” are its flexibility of application, thanks to the compact size of its components, and the fact that it is a dual dry clutch (the type of clutch that guarantees the highest degree of efficiency in terms of fuel consumption among all automatic transmissions). If we compare "Dry" clutches with oil bath ("Wet") ones, we can safely say that the former dissipate energy only during the actual slipping phase of the gear change and on pick-up, whereas wet clutches, which always operate in an oil bath, introduce losses due to viscous friction such as those of conventional automatic transmissions even when they are not in operation. What's more, they require forced cooling with oil and therefore continuous energy expenditure to drive the dedicated oil pump (absent in the case of "Dry" clutches). Moreover, a "Wet" automatic transmission requires approximately 4.8 litres more oil than the "Dry" version, again for reasons of clutch cooling (in this way, weight is added and losses due to splashing increase). When all these effects are added together, a “Alfa TCT” is found to be approximately 6% more efficient than the corresponding "Wet" one in terms of consumption. Last but not least, the advantages of the "Dry" clutch include the lower cost and the increased ease of installation. Lastly, it should be remembered that the new “Alfa TCT” boasts a generous 23 public patents split into 3 areas: gearbox control, gearbox mechanics and gearbox actuator.