As the motoring world slowly moves away from fossil fuels, pressure relief valves have become more important than ever to allow for the safe creation and transportation of biofuels.
These more environmentally friendly fuels, alongside similarly sustainable electrofuels, will see use even as consumer motoring transitions entirely to electric cars, as there will be a need for them in aviation, shipping and motorsport.
Whilst electric motorsports do exist, the most popular racing disciplines in the world are moving towards some kind of sustainable fuel, either biofuels, e-fuels or a combination of both.
This means that pressure relief is a major issue not only when it comes to the fuel tanks on the cars, but also the fuel taken to each racetrack.
However, purely based on the technology used in the cars themselves, arguably the most critical time for pressure management in motorsport is a brief period when a fuel so potent it was compared to rocket propellant was used in the cars and changed everything.
Turbocharged Pressure
The 1983 Formula One World Championship made history by being the first to be won with a turbocharged engine. This was not necessarily a surprise, but what was a surprise was that the team that won the championship that year was not the first to introduce high-pressure turbocharged engines to F1.
In 1977, the French manufacturer Renault took advantage of a previously unused clause in the technical regulations at the time and designed a 1.5-litre turbocharged engine as opposed to the 3.0-litre naturally aspirated engines that the rest of the field was using.
The resulting Renault RS01 was an ambitious but innovative failure. Nicknamed the “Yellow Teapot”, the RS01 had a remarkable tendency to overheat and blow up, in part due to a lack of understanding of the strains the turbo boost can have on the engine.
However, the relatively small Renault team stuck with the technology, partly because turbocharged engines had won in other motorsport categories, but also because the potential was significant.
Whilst half the size of a typical F1 engine of the time, the compressed air meant that they could produce more power and have better acceleration, although it took some time to find a way to avoid a delay in power as the turbocharger spooled up.
The technology would evolve quickly; the updated Renault RS10 would win a race just two years later.
Combining a twin-turbo engine with an aerodynamic concept known as ground effect, the RS10 managed to improve the reliability, performance and engine response, proving that turbocharged cars were the future of racing. This created a scramble by the other teams to catch up lest they be left behind.
Loaded Up With Rocket Fuel
By the end of 1981 and the unveiling of the Renault RE30, it appeared that not only was a turbocharged World Driver’s Champion an inevitability, but it seemed increasingly likely that a yellow and white Renault piloted by star driver Alain Prost would be the one to make pressure relief history.
Unfortunately, Ferrari would beat Renault to the Constructors’ Championship in 1981 and 1982, and were it not for two horrific accidents, the Ferrari 126C would have also been driven by the 1982 Driver’s Champion as well.
In 1983, with new rules and a highly competitive Renault RE40 designed to suit Alain Prost’s driving style, Renault were the class of the field, and Mr Prost won more races than any other driver.
Unfortunately, a new challenger appeared with a turbocharged engine in the form of a BMW-powered Brabham BT52.
The arrow-shaped car was filled with innovation, but arguably the one that took them to the world championship was housed within the small, high-fuel tank.
With mid-season difficulties for Brabham keeping Alain Prost ahead, Brabham used a fuel that used toluene, a derivative of petrol that could burn quicker and produce more heat, both of which helped the BMW engine to produce significantly more power and boost pressure.
So powerful was this toluene-based fuel that there was speculation that it was similar in composition to fuel used by the V-2 rockets during the Second World War, although this connection was quickly debunked.
The rocket fuel and the ability for the BMW engine to manage the pressure were enough for Brabham’s Nelson Piquet to win the championship at the final race in South Africa by finishing third, whilst the turbocharger on Mr Prost’s Renault gave up.
Renault launched a complaint about the fuel, claiming it was illegal, but the complaint was not upheld, and the power and boost pressure from the turbochargers only increased. At one point, a qualifying engine had a boost pressure as high as 5.4 bar for a total power output of around 1,300 bhp.
Eventually, F1’s governing body limited boost pressure to try to reduce the advantage turbochargers had before banning them outright for over 25 years.
