How Porsche turned its WEC LMP1 winner into an F1 beater
|By Matt Somerfield||Thursday, April 12th 2018, 16:45 GMT|
This week, Porsche managed to shatter the unofficial Formula 1 lap record around Spa-Francorchamps with an upgraded version of its 919 Hybrid.
It's rare that we get to see what racing cars are capable of once their programmes come to an end, but Porsche has done something incredibly special by creating the 919 Evo tribute, a machine that totally ignores the technical regulations that held back the potential of its World Endurance Championship-winning counterpart.
The lap record it beat around the Belgian Grand Prix venue was relatively fresh too, having been recorded last year by Lewis Hamilton in his Mercedes W08 - a car that also had a serious increase in downforce thanks to the new Formula 1 regulations introduced in 2017.
Neel Jani's target time to beat was a 1m42.553s - a feat that seems even more implausible if we consider the standard car managed a 1m54.097s in WEC qualifying in 2017. But Jani smashed that time, recording a 1m41.770s that was 0.783 seconds quicker than Hamilton's pole lap and more than 12 seconds faster than the WEC pole lap.
But how did the car achieve that time?
Firstly, it's worth noting that as part of the project it was decided that the 919's powertrain would remain untouched, as the Evo continued to be powered by Porsche's turbocharged two-litre V4 engine with two energy recovery systems.
But without the limitations imposed by WEC's LMP1 regulations, the development team was free to ignore fuel flow constraints and upped the flow rate to allow the Evo's engine to deliver 720bhp in its own right (up from 500bhp) while still using regular race fuel.
As part of the efficiency matrix that shackled the 919 Hybrid on its 2017 pole lap, the driver only had 6.37 megajoules of energy at his disposal. But for this run, Porsche exploited the energy recovery system's full potential, gaining another 40hp as it utilised 8.49MJ of energy.
Combined, that meant the powertrain's output increased from an already-healthy 900bhp to 1160bhp - an astonishing achievement given it was done with the same equipment and fuel, albeit with a number of software updates.
Increasing the car's output by a third would be useless without being able to control it, so it's no surprise that under the car's frame numerous changes had to be made too. The Evo utlises a four-wheel brake-by-wire system, giving the driver more control in yaw. New front and rear suspension wishbones had to be crafted in order to endure the higher loads that the car would be put under.