A number of leading teams at this weekend’s Kyalami 9 Hour are facing challenges as a result of the South African circuit’s unique conditions including its high altitude.
The track’s exceptionally high altitude of 5,029 ft (1,532 meters) places it just marginally lower than Utah Motorsports Campus, for which the SRO Motorsports Group introduced a high-altitude-specific Balance of Performance two years ago.
High-altitude conditions typically favor turbocharged cars over naturally-aspirated configurations, causing problems for the three leading manufacturers at the Intercontinental GT Challenge powered by Pirelli season finale: Porsche, Mercedes-AMG and Audi.
“You can feel that here with the altitude, there is less power from the engine,” Mercedes-AMG Team GruppeM Racing’s Maro Engel told Sportscar365.
“I think that is certainly the same for all the naturally-aspirated engines, and you can also feel that there is a little bit less downforce because the air is thinner. It’s definitely very feelable.”
Porsche’s Laurens Vanthoor echoes Engel’s thoughts and expects a “tough race” for teams running the Porsche 911 GT3 R and Audi R8 LMS GT3 Evo compared to turbocharged cars.
“[On Thursday] I did a half race stint [in night practice] and the Bentley, the BMW, all the turbo engines drive away two or three car lengths so you can’t try and overtake,” he explained to Sportscar365.
“You can be as quick as you want but if you’re not going to get by the car in front of you, you have to take risks in traffic and there is more potential for mistakes.
“I guess it’s going to be a tough race from that point of view for the Audis and us, but it is how it is.”
Audi Sport Team WRT’s title hopeful Frederic Vervisch expressed concern on Thursday that the Audi’s lack of power and straight-line speed will hurt his championship chances, meanwhile.
The pair of Audis registered 233.2 and 232.7 km/h in the speed trap during Night Practice, compared to the top speed of 241.6 km/h registered by a Bentley Continental GT3. The Porsches were marginally quicker than the Audis, while the Mercedes’ top speed was 234.2 km/h.
“We are struggling with it, for sure and I think it will be quite difficult to fight in the race,” Audi Sport Team Land’s Markus Winkelhock told Sportscar365.
“First of all, to defend the position, and if you have a slower car in front of you it’s quite difficult to overtake. I think it is going to be not an easy race but I can’t change it anyway and when I get in the car, I’ll give 100 percent.”
Mercedes-AMG’s head of customer racing Stefan Wendl believes that a number of other factors at Kyalami, besides the altitude, play into the hand of turbocharged cars.
“We expect [turbo cars] strong here because this is one of the tracks that fits those cars very well, but not only from the altitude,” he told Sportscar365.
“The layout of the track is very flowing, fast and mid-speed corners and only three slow corners where the traction is needed.
“The tarmac is very new so there is less degradation than, for example, in Suzuka. All those topics play in the hand of the strong cars.
“This is something that maybe we have to live with but we will see after the [Pole Shootout] where we are exactly, and then maybe we have another round [of BoP changes]. So far, nothing looks so strange.”
Kyalami is listed as a Category C track in the SRO’s BoP system instead of using Utah Motorsports Campus’ Category H classification.
An SRO spokesperson confirmed to Sportscar365 that BoP changes could be made prior to the race depending on data collected during today’s Pre-Qualifying, Qualifying and Pole Shootout sessions.
Paddock Supportive of SRO’s BoP Process
Drivers and team figures up and down the paddock have expressed overwhelming support for the SRO’s BoP process, praising decisions made by technical director Claude Surmont.
“I fully trust the SRO and Claude,” added Wendl.
“I think he did a very good job at the past races for BoP, and everything was really tight, and more or less, at each event there was [a different] car in the lead so there is some circulation, which is important.
“Even if the BoP is tight but always the same car is fastest, then something is wrong, but this is not the case.”
Earl Bamber described the SRO as “the best in the business” at BoP decisions, meanwhile.
“These days, in every championship, they are doing fantastic jobs everywhere and I think the biggest thing we complain about these days is raceability, we don’t complain about lap time spread in the classes,” he told Sportscar365.
“If [our biggest concern] is raceability, it’s not that bad of a problem to have, considering where we came from five years ago.”
John Dagys contributed to this report