Tweaked Porsche 919 Hybrid goes fastest at Spa

by John Glynn | Apr 10, 2018 | Porsche News, Race and Rally

In an interesting PR move, timed to make the monthly motoring press just as its former WEC rivals take to the track at Spa Francorchamps for the first race of the 2018 World Endurance Championship on May 3-6, Porsche has run a modified version of its lightened 919 Hybrid with over 50% more downforce around the Spa Francorchamps circuit, setting a time twelve seconds quicker than the WEC pole position lap from last year’s Spa Six Hours.

Porsche took 39 kilos off the 919 LMP1’s dry weight in race trim by losing the 919 race car’s air jacks, lights, air conditioning, windscreen wiper, race control trackers and other parts, allowing the car to top the scales a smidge under 850 kilos. The maths here are a little strange, as the minimum dry weight allowed under LMP1 regs is 875 kilos, so you would think it might have been lighter, but anyway.

The car was then fitted with a much-improved aero package, including a larger front wing and a massive rear wing, both fitted with hydraulically controlled drag reduction systems (DRS) to strip away downforce on Spa’s long Kemmel Straight. Together with changes to the floor and turning vanes, the downforce produced by this tweaked 919 was 53% higher than the WEC-legal 919 LMP1 that took pole at Spa in 2017.

The real benefit of the improved downforce at this particular track is that the driver can run the car absolutely flat out from the exit of the La Source hairpin, through Eau Rouge and Radillion and the Kemmel Straight up to the braking for Les Combes: a distance of more than 2 kilometres. We don’t know the top speed difference with the higher entry speed and DRS being used, but I guess that it’s not a small number.

The lighter weight and higher downforce was pushed along by more horsepower from the 2-litre V4 Turbo engine, which enjoyed substantial improvements when freed from the fuel consumption limits imposed as part of the endurance racing regs, where the fuel usage at Spa was capped at just under 2.5 litres per lap. Set to use as much fuel as the engine could handle, power from the V4 rose from 500 bhp to over 720 horsepower – approaching 50% more. The hybrid systems were tweaked to add ten percent more power, so 440 horsepower.

With 440hp driving the front wheels and 720 bhp driving the rear wheels, Weissach added reinforced wishbones to all four corners, added an “actively controlled lockout system” (whatever this does, it was not fitted to the WEC compliant 919) and a new brake-by-wire system to limit yaw as the car piled through Spa’s twists and turns. With so much more power, downforce and electronic controls, the car set a lap time some three quarters of a second quicker than Lewis Hamilton’s F1 pole position lap from 2017.

Obviously there is some satisfaction for Porsche in demonstrating the potential of an unleashed 919, but it is hardly a like-for-like comparison with cars running in a fully FIA compliant form in higher ambient temperatures later in the year, so what the exercise actually tells us is hard to say. However, there can be no doubting the intention of the timing of this release, which will definitely be a talking point at next month’s Spa 6 Hours and will also form part of the chatter all the way through the 2018 season.

WEC mandarins might be pretty cross at Porsche’s timing, but spectators have every right to feel equally annoyed that the governing body won’t let manufacturers spending millions of Euros in race car development run these cars at their full potential, all of the time. Instead, WEC (and F1) fans are challenged to follow quieter racing with arbitrary fuel economy targets. Obviously endurance is partly about deploying energy with intelligence but capping the engines at less than two-thirds of their potential is a huge downside: a 2-litre engine making 720 bhp is something quite special and worth shouting about.

I like the 919 hot rod story, but am not sure what to take away from it other than Volkswagen is pretty unhappy with the handicaps applied to its prototypes and wants to make a point right at the start of the first season it won’t be running with Porsche or Audi in LMP1. The other big stone flipped over by this is that, if an F1 car was allowed to pick a time and date to run at its full potential with unhindered engine power, full electronics and optimum aero around Spa Francorchamps, then a tweaked 850-kilo LMP1 car probably wouldn’t see it for very long. Whether that matters or not is another story. Pretty sure I know which of my race friends will squeak the loudest.