When Grand Prix racing started there were no technical regulations to govern the sport. Manufacturers simply built the fastest car they could and drove it as fast as possible. By 1934 however speeds were becoming an issue, so to try and slow the cars down the governing body limited the maximum weight to 750kg (this for the car excluding driver, oil, fuel and tyres). The theory being that it would limit the large heavy engines and so control speeds. What the regulation failed to predict was the massive investment the German teams (Mercedes and Auto Union ) would make, eventually producing over 550 bhp from their supercharged engines. In 1938 the engine size was limited to 3 litres (still supercharged if required), and this limited the power.
When racing resumed after the second world war, the engine regulations continued to effectively limit the maximum power produced to be below that peak achieved in 1937. From 1947 – 1953 Formula 1 regulations limited engines to 4.5 litre atmospheric and 1.5 litre forced induction, power produced was up to 425 bhp. Note that the 1952 and 53 world drivers championship was held to Formula 2 regulations, due to the small number of competitive Formula 1 cars available, however a number of Formula 1 races were held.
From 1954 to 1960 the engine size was reduced to 2.5 litre atmospheric engines, and although 750cc forced induction engines were allowed in the regulations none were ever built. The maximum power was reduced to 290 bhp.
1.5 litre engines were mandated from 1961 – 1965, and although initially these reduced speeds, by the end of the period the cars were lapping faster than they had in 1960. Maximum power improved dramatically rising from 15 bhp in 1961 to 225 bhp by 1965.
To combat the improving speeds of sportscars, Formula 1 increased its engine size in 1966 to 3 litres atmospheric and 1.5 litres forced induction. These rules stayed constant until 1986, but initially all teams used the 3 litre engines. The most numerous engine to be used during this time was the Cosworth DFV, this started out producing just over 400 bhp in 1967, but ended up producing 510 bhp by 1983. This was still below the figure achieved by the pre-war German cars.
In 1977 Renault entered Formula 1, and decided to exploit the 1.5 litre forced induction option in the engine regulations. It had been there since the start of this regulation period, and everyone else had ignored it. While the initial engines were unreliable and prone to spectacular failures, they were tremendously powerful (while they lasted), and by 1980 they had demonstrated the advantage of the concept to the extent that Ferrari also produced a turbocharged engine for 1981. BMW were persuaded to join in 1982 by the Brabham Team owner (Bernie Ecclestone) and by the middle of 1985 the entire grid was using 1.5 litre turbocharged engines. During 1986 the engines were rekoned to be producing 950 – 1000 bhp during the race, but with the boost turned up for qualifying (and engines only required to last three laps) over 1350 bhp was possible. The actual maximum power produced is not recorded anywhere, it was above what the engine dynamometers could measure.
During this turbo era, fuel was unlimited (although limits in boost pressure and maximum fuel tank size would be introduced in 1987 and 1988) as was engine development and the number of engines that could be used during the season. Engine life was so short that teams would put a new engine in for each practice session, and one for each qualifying run, with a fresh engine for the race. So each driver would use perhaps eight engines during each race weekend. With the BMW engines re-using old road car blocks (as the heat treatment after being run for 90,000 miles made those more reliable than freshly cast items),this was an expensive way to go racing. Without ERS taking further energy out of the exhaust gas, the cars would spit flame on the over run, and with the V6 engines having twin turbo chargers, blown diffusers were used by most teams. However as big turbos were needed to produce the big power required to remain competitive, they suffered from significant turbo lag (the time between the driver pressing the throttle pedal and the engine responding with max power could be a second or more). This made the cars particularly difficult to drive especially in the wet. While much quieter than the V12’s and V10’s that would follow, these engines were comparable to the 3.5 litre V8’s that began to be re-introduced in 1987.
With the capacity for atmospheric engines increasing to 3.5 litres in 1987, and the boost pressure limited (4 bar in 1987 and 2.5 bar in 1988) the power advantage of the turbos began to be erased. In 1987 the Cosworth DFZ was producing 575 bhp, but the BMW turbo was still able to produce 900 bhp. For the following year, the turbo power was reduced to 675 bhp (at 12,500 rpm) for the dominant Honda, while the less fuel efficient Ferrari could reach 690 bhp (at 12,800 rpm). Cosworth responded with the DFR which produced 620 bhp (at 11,000 rpm). Interestingly these engine speeds are very similar to the low revving engines that many are complaining about today, and the power is much less.
Forced induction was banned from 1989 and until 1994 the rules were for 3.5 litre engines. With many manufacturers producing Formula 1 engines there was a great deal of variety, with V12, V10 and V8 engines being produced. In 1989 these produced maximum power at 14000 rpm, the V12’s and V10’s were much louder than the V8’s which peaked at below 11,000 rpm. Power ranged from 675 bhp (Honda V10) to 560 bhp (Yamaha V8). By 1994 the Ferrari was producing 820 bhp at 15,800 rpm.
From 1995 until 2005 the engine size was reduced to 3 litre, and while Ferrari persisted with their V12 for the first season, by 1996 all engines were V10’s. By the end of the regulation period power had improved to 950 bhp largely thanks to the increased rotational speed of the engines, with engines running to over 19,000 rpm.
From 2006 until 2013 engines were reduced to 2.4 litre V8’s with far greater restrictions on the specification of the unit (bore, stroke, V angle, only two inlet and exhaust valves per cylinder, etc.). Engine speeds continued to climb and in 2007 a rev limit of 19,000 rpm was introduced, and this was further limited to 18,000 rpm in 2009. This was done to increase reliability (with each driver only allowed eight engines per season). Although with these high engine speeds the exhaust note was high and loud, the restrictive regulations meant that all engines sounded the same. Power during this period is estimated at 740 bhp, but this was before the further rev restriction in 2009.
In 2014 came the new era of 1.6 litre turbo charged engines. While these have a rev limit of 15,000 rpm, the fuel flow restrictions mean it is not efficient to run the engine at that speed. With the ERS contributing a significant amount to the overall power available, these are much more drivable than the previous generation of turbo cars, and produce a similar power output to the V8’s that preceded them. However there have been complaints that they are not spectacular enough, and so the FIA is considering a proposal to re-introduce 1000 bhp cars again. This could be done by increasing the fuel flow limit and potentially the rev limit.
However if drivers are going to be able to use that power (and not save fuel for the whole race) the fuel capacity will need to increase as well. The cars will still have ERS, so we are unlikely to see the return of flames coming from the exhaust, and the sound is still likely to be muted, as that energy should be being recovered for use elsewhere in the lap. However the extra power will make the cars more difficult to drive, and increase the possibility of driver error. If anything it is this lack of driver error (missed gear shifts, running out of fuel, running out of tyres, missed braking points) that has impacted on the quality of the racing when compared to 30 or 40 years ago. Driving an F1 car is difficult, but at times from the comfort of your living room it doesn’t look that way, if these new cars meant we saw drivers having to work harder to avoid mistakes it may highlight the differences between the truly great drivers and the merely very good.