Porsche is taking a gamble with its aerodyamic configuration at this weekend's 6 Hours of Silverstone, with the German manufacturer confirming a low-downforce setup for the World Endurance Championship season opener.
Both 919 Hybrids will run with low-downforce bodywork, in a move that will almost certainly curtail their performance on the 3.6 mile circuit.
Low-downforce aero kits are typically reserved for the 24 Hours of Le Mans, but the new LMP1 regulations have inspired Porsche to change its strategy.
In 2017, LMP1 teams are allowed just two aero kits for the season, down from three last year. That means one high-downforce kit for the eight six-hour rounds which are held on cornering-dependent circuits, and one low-downforce kit designed specifically for the long straights at Le Mans.
Team Principal Andreas Seidl said the decision was motivated by the new regulations, and is based on maximising development of the high-downforce kit ahead of its expected debut at the 6 Hours of the Nurburgring in July.
“With regards to reliability, we have been fine at our 30-hour test in Paul Ricard as well as at the Prologue in Monza," said Seidl.
"We feel well prepared for the first six-hour race. However, with regards to lap-times, Silverstone is going to be difficult."
"In the name of cost saving, the 2017 regulations permit only two aero kits per season. We have managed our resources the way that we focus on developing and testing our Le Mans aerodynamics until the third race of the season is over."
"This means low downforce for the benefit of low drag and this unavoidably will be a disadvantage in Silverstone. After the Le Mans 24 Hours in June we will consequently arm the 919 with more downforce for the remaining championship rounds."
Seidl added that other regulation changes, most notably regarding tyre usage, would make this year's opener particulalry challenging.
"Another new challenge that is addressed by the rules is the reduced amount of tyres," he said.
"Two fuel tank fillings – in other words about 90 minutes racing – with the same set of slick tyres will be standard. This requires very sensible tyre management.”
Toyota confirmed at Monza that it will use its high-downforce kit at all rounds bar Le Mans, with the low-downforce kit making its only six-hour appearance on the additional 'third' entry at Spa in May.
That means the Porsches may struggle to match the pace of their rival Toyota TS050s at Silverstone, and potentially Spa.
"Historically, Silverstone isn’t our strongest circuit and I don’t see us being the favourites this year either – especially as we are aerodynamically compromised," said defending world champion Neel Jani, who shares the #1 Porsche with Andre Lotterer and Nick Tandy this weekend.
"But, still we want as many points as possible."
“Last year we only won the opening round in the aftermath of scrutineering, but it was the beginning of an incredible season,"
In 2016 Porsche won the 6 Hours of Silverstone by default after the 'winning' Audi was handed a post-race penalty. The team went on to win six out of nine races last season, securing a sweep of the drivers', teams' and manufacturers' world titles.
The WEC 6 Hours of Silverstone takes place on Sunday, April 16th at 12:00 local time.