The Formula 1 engine, for all of its sophistication and precision, is ultimately a ferocious monster. It has a terrible growl when awakened, deafening roar as it accelerates and a furious wail when spun to full speed. It gulps air and fuel, and exhales fire. It shakes violently. The only way to appease the monster is to keep it well fed and well exercised. A magnificent beast.
The Formula 1 engine is a beast defined mainly by the rules determined by the FIA, the international motorsport governing body.
Simplified the engine is a 90 degree V8 naturally aspirated with 2.4 liters of displacement; a block and cylinder heads constructed of aluminum alloy; 4 camshafts; 4 valves per cylinder; fuel injected and computer controlled; oil lubricated and water cooled.
Formula 1 engines are very lightweight, by FIA rule they must have a minimum weight of 95 kgs (209 lbs). In fact, most engines weigh less than 95 kgs and require ballast to be added to bring them up to FIA spec. This while maintaining the structural rigidity necessary to hold up the entire back end of the car, including the gearbox, rear wing and rear suspension. Each component of the engine not outlined by the FIA rules is minimized in weight and size to provide the least resistance to achieving speed. For example the 2009 Toyota engine (taken apart by RET magazine) utilized hollow camshafts with even the lobes of the camshaft themselves are hollowed out. Every gram is considered, the spark plugs weigh as little as 11 grams (Champion). For comparison a conventional spark plug weighs close to 65 grams.
Arguably, the most intriguing aspect of the Formula 1 engine is the speed at which it can rotate, up to 20,000 rpm. However, this speed is mandated at a maximum of 18,000 rpm by the FIA. For comparison a typical Nascar or Indy car engine spins up to about 10,000 rpm. The primary reason the engine can achieve such high speeds is extremely short length of the piston stroke. The stroke of a Formula 1 engine is approximately 40 mm, less than half as long as the bore is wide (98 mm). The shorter the distance the piston has to travel the faster the engine can spin.
The physics of spinning an engine far above 10,000 rpm prevent the conventional coiled metal valve springs from closing the valves fast enough to keep up with the cycles of the engine. This is overcome by the use of pneumatic valve springs. The valves push against a compressed cushion of air which is able to react and close the valves much faster than a metal coil spring.
Engines in Formula 1 for 2011 are built to last between two or three 2 hour long races including three practice sessions (1 hr 30 mins) and one qualifying session (maximum of 1 hr). The FIA rule allows for the use of eight engines for the duration of the season, which is 19 races, and there is a 10 grid spot penalty for using a ninth engine.
There is no opportunity to rebuild the engine after each session or each race even though some Formula 1 teams have the means and manpower to do so. Once an engine is homologated it is effectively sealed, with only ancillary items allowed to be changed, such as coolant, oil, spark plugs, and filters. As a result a certain amount of durability must be built into each engine often at the sacrifice of weight and power. That being said, everything on a formula 1 car is built on the edge of reliability in order to gain every last bit of performance. In effect, the fastest car is often the car that comes closest to failure without actually doing so.
Material selection is critical to both reliability and performance of a Formula 1 engine. By FIA rule the engine block and cylinder heads are aluminum alloy, and cannot be made from magnesium or other high tech metal or composite. The crankshaft and camshafts must be made from single pieces of iron alloy (like steel). The pistons are aluminum, connecting rods titanium, valves titanium. In addition, material coatings and treatments are also used to give more ordinary materials like aluminum or steel the ability to withstand the massive forces exerted in Formula 1. Coatings must not exceed specifications: total coating thickness does not exceed 25% of the section thickness of the underlying base material in all axes or 0.8mm.
This is the sound of a Formula 1 engine being put through its paces.
A Formula 1 engine under construction-- be warned the sound is loud on this one.
As of the 2011 season four manufacturers make engines. Cosworth, Ferrari, Mercedes-Benz, and Renault. Each team purchases their engines from one of the four manufacturers and adapts them to their own chassis. The cost of a formula 1 engine is astronomical, however with the purchase comes full service at the shop and at the racetrack.