For all the hours of TV coverage F1 attracts, most fans only get to see the glossy streamlined bodywork and not the parts under the skin that make the go. Although the ultimate speed of an F1 is mainly about aerodynamics, it is only by being aided by these mechanical and electronic systems that the car can go so fast.
For Enzo Ferrari, the heart of the car is the engine. In a racing the car the engine itself has a double function, not only to power the car but the engine also forms part of the cars structure.
Current F1 engines are a tour-de-force in design; the engine capacity is just 2.4 litres, not much more than the average family car. But unlike the family car the F1 engine produces over 700 horse power and revs to a limit of 18,000rpm. Before the rev limit was introduced to cap escalating speeds, teams were running engines to 20,000rpm! Although displacing the same capacity as a family car, the F1 engines layout is totally different. It has eight cylinders and these are arranged in two banks of four. Each bank meeting the crankshaft at the bottom of the engine at 45-degrees. This layout is known as a V8 format.
Being bolted to the back of the survival cell and having the gearbox bolted on behind it, the engine has to carry the loads passed through the car by the wings and suspension. Despite this architectural function, the modern F1 engine is tiny just over 50cm longs and just 40cm high. Indeed the engine is so small, that the rules now mandate a minimum weight and Centre of Gravity height for the car. Teams in the early 2000’s were able to make the 2.4l engine weight well under 90kgs. Now the engine must weight 95kg.
In order to create the huge power outputs and reliability needed to last three grand prix, the engine is supported by a range of auxiliary systems. The engine is fuel injected; the hardware for this sits inside the tall airbox mounted atop the engine. Fuel injectors spray fuel into the inlets at 100bar, which fifty times more pressure than in your car tyres! The throttle opening and the fuel injection are controlled by the throttle pedal. F1 cars use a fly-by-wire pedal. This means the peal is not mechanically connected to the engine, but controls it via electronics and it’s a hydraulic actuator that actually opens the engines throttles. All of this control is managed by the engines control unit (ECU). This is now a Standard ECU, often termed SECU by the teams and its manufacturer. Surprisingly the unit is supplied by a subsidiary of McLaren and the software developed in cooperation with Microsoft. The unit is an unusual triangular shape, is often fitted below the drivers legs.
The fuel is ignited inside the engine by spark plugs which are tiny being just 8mm in diameter and 40mm long, weighing in just 10grammes.
Then the burnt fuel and air pass through the exhausts, which are one of the few handcraft parts on an F1 car, they are welded from thin sections of a special high temperature metal called Inconnel. Each set of exhausts take several days to make and end up weighing just 3Kg.
Keeping the engine cooled is critical to the reliability of the engine; an f1 engine is cooled by water and oil. With the oil also lubricating the moving surfaces inside the engine. Although is note purely water that is pumped around the engine, but instead a water based mix of coolant, not dissimilar to that used in road cars. The water absorbs the heat from the engine and passes out of the top of the engine into two large radiators mounted in the sidepods. The air passing through the sidepods extracts heat from the coolant in the radiators and then the coolant is piped back into the bottom of the engine to start the cycle again.
Oil takes a more convoluted route; the oil is stored in a tank mounted to the front of the engine. This then gets pumped to an oil radiator in the sidepod. Now cooled it is then directed to the major moving parts inside the engine; the crankshaft, the cams and some oil is even sprayed under the pistons to keep them cool. This oil then drains into the sump at the bottom of the engine, where is collected by pumps and passed back to the oil tank.
Feeding the engine with enough fuel to last the race distance is the fuel tank. This is special aerospace style tank, made from a rubberized composite material that is effectively bulletproof. The fuel tank sits inside the survival cell between the driver and the engine. It can carry over 150kg of fuel and itself weights just 7kg. As refuelling is now banned in the race, team’s fit two small connectors to plate in the side of the tank to allow the tank to filled and emptied. As the car laps, the fuel inside the tank is shaken around with the same force as the driver suffers. To prevent the fuel being thrown violently around inside the tank, it is fitted with internal walls that compartmentise the tank to keep the fuel in place.
Like the engine the gearbox has a dual purpose, to provide the seven gears and also form part of the cars structure. The outer part of the gearbox is known as the case; this can be made from either cast metals such as aluminium or titanium, or moulded from carbon fibre. The rear suspension and crash structure are then bolted to this case. As the gearbox sits in the aerodynamically sensitive area around the rear of the car, teams like to make the case a slim and low as possible in order to gain downforce from the surrounding bodywork. Teams have to carful the gearbox is strong enough to act as part of the structure and still meet the demands of the aerodynamicist.Inside the gearbox there are eight pairs of gears, seven forward gears and a reverse gear. The driver doesn’t select the gears with a lever as on a road car, but via paddle on the steering wheel. Via the cars SECU this then control hydraulic actuators shift the gears. The usual reference for fast shift speed is the ‘blink of an eye’, in F1 terms this is too slow. These semi automatic gearboxes have become ever more complex and now the gears can be selected nearly instantaneously, known as a seamless shift.
Other mechanical parts hidden by the bodywork are the brakes; F1 cars use disc brakes in common with most road cars. To provide the 4G braking force, the brake discs are squeezed by large callipers. These have six pistons each pressing a brake pad against the disc surface. However the discs themselves are not made from heavy cast iron, but instead carbon fibre. This makes the discs some ten times lighter than those on road car and able to reach far higher temperatures. F1 brakes reach temperature of over 800c in use and keeping the brakes form overheating is the job of the brake duct. This is a complex aerodynamic part filling the inside of the wheel and feeding air to the brake disc and caliper.
Unlike the throttle pedal, the brakes are purely mechanical and driver operated. The large brake pedal operates two cylinders that pass the braking fluid to each of the cars four brakes. No electronics, ABS or power assistance is allowed. The driver left foot has to press with 100kg of force to get the car stopped in time from high speed.
Lastly Steering, like the brakes the steering has to be achieved without any electronics, although fortunately for the driver’s power steering is allowed. Its layout is much the same as for a road car; the steering wheel rotates a steering column, which then in turn moves the steering rack. At tracks like Monaco teams will alter the steering rack and track rods to allow for a tighter turning circle. Plus we have all seen the drivers remove the steering wheel when he gets out of the car. The steering column has a special connector that when pulled unlocks the wheel; this makes it easier for the driver get out of the tiny cockpit.