HOME 355 F1

 

Technology applied to road use

The gearbox and clutch are the same as those used on the F 355 with a conventional manual gear change. This is a 6-gear plus reverse mechanical gearbox with a single-plate dry clutch. The gearbox has been fitted with an electro-hydraulic control system operated by levers on the steering wheel that take over from the conventional gear stick and clutch pedal.

Operation: starting

When starting, select either the first, second or reverse gears and then press down on the accelerator. These gears can only be engaged when the car is standing still and with the brakes on. As a result the system performs the following operations:

once the driver has selected the gear, the system opens the clutch and engages the selected gear;

when the driver presses the accelerator the system begins to close the clutch gradually, based on the following information: engine revs; angle of the accelerator pedal; speed of pressing down on the accelerator pedal. Specific software functions automatically guarantee correct engine and clutch management in all starting conditions, including those found during urban use or on an uphill slope.


  Changing gear

The driver operates the lever located behind the wheel, DOWN to change down or UP to change up. When the system receives this command it performs the following operations:

it checks that the conditions are right (engine revs and car speed) to make the requested gear change;

it evaluates engine torque, checking by means of a serial dialogue line (CAN) between the Bosch Motronic and Marelli control units, with the clutch still closed, in order to avoid over-revving or slipping as the clutch is opened;

it opens the clutch;

it monitors the engine and provides targets for both revs and torque, co-ordinating the selection and engagement of the requested gear;

it checks that the selection and engagement operations are completed;

it gradually closes the clutch, at the same time checking torque delivery.

This sequence of operations in gear changes under sporting conditions is carried out in less than 200 milliseconds. The system is designed to assist the driver in checking the engine while avoiding the need to manage the accelerator during gear changes.

This means that the driver can change gear as he likes, with the accelerator hard down, partially down or released. The system adapts management of the gear change to engine conditions which are rated on the basis of the following fundamental parameters:

throttle valve opening;

speed of throttle valve opening;

engine revs;

gearbox entry revs;

car speed;

gear selected;

gear requested in the gear change;

engine temperature;

mode of use selected (normal, sport, automatic, low grip).

Gears ratios

115/46
219/41
323/37
426/33
529/30
636/31
Reverse15/42

 

Origins of the design

Application: form Formula 1 to the F 355

Guidelines for use

Performance