IMSA: DeltaWing explains latest development updates, gearbox and differential

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In an effort to improve overall performance, the DeltaWing Racing Cars team has made numerous updates to the revolutionary DeltaWing coupe in recent weeks. As the team heads to the Mobil 1 SportsCar Grand Prix Presented by Hawk Performance at Canadian Tire Motorsports Park – a fast, flowing track that allows the innovative sports car prototype to maximize its straight line speed – team manager Tim Keene and race engineer Alan Mugglestone highlight these updates.

The main areas of development have been the gearbox and the differential. As the coupe increases in performance, the balance between the car’s light weight and the need for stronger components has been a very delicate proposition. The team incrementally added to the strength and layout of the gearbox, with wider gears, stronger bevel gears and now a stronger mounting. The team works with suppliers for these components but the bulk of the DeltaWing coupe’s parts are designed and built by the team.

The team has also successfully tested a differential, which raced for the first time at Watkins Glen. The DeltaWing was originally designed with a very complicated and experimental electronic differential that would not only help the car drive, but turn under braking. For a number of reasons, the concept was abandoned in favor of an “open” differential. The new differential performed well at tests last month and helped put the DeltaWing coupe in the top seven for much of the first two hours at The Glen, while the car’s fuel efficiency put the car in the lead during pit stops before a problem with the gearbox mounting ended the day.

Keene and Mugglestone are optimistic heading into the weekend at CTMP, where the team saw competitive times last season.

“The DeltaWing coupe is more suited to a track that allows constant momentum,” said Keene. “The Daytona Prototypes have so much more horsepower and torque off of slow corners than we do, so the more we can keep the smaller engine revved up the better it is for us – and these next two tracks lend themselves to that. Given the weight of the car, our aero is very efficient for high speed because most of our downforce comes from the bottom of the car rather than large wings or dive planes. It’s a much more efficient way to create downforce with less drag, which is the car’s basic concept.”

“The DeltaWing concept doesn’t produce a huge amount of downforce compared to a DP or a P2,” Mugglestone added. “It was designed to be a very low drag, fuel efficient car. So when you lose a small amount of downforce as we did when we went from the roadster to the coupe, it’s a much larger percentage. The switch to Continental tires – with a bit less width on the rear tire – enabled us to modify the floor and get some of that downforce back.

“With the limited slip differential we’re running now, an unloaded wheel will transfer torque to the loaded wheel. So we picked up traction in the corners, which puts the gearbox under the same stress but for longer periods of time. We’ve backed off the horsepower to the point where we know the engine is not breaking the gearbox, because we’re below the recommended torque. We’re going faster because we have more grip, both from the tires and from the fact that we now have two rear wheels driving forward. The stronger gearbox should be able to handle that.”

As IMSA finds the balance of performance between the three disparate members of the Prototype class – the Daytona Prototype, the P2 and the DeltaWing coupe – where does the DeltaWing slot in alongside its competitors?

“We’re somewhere between a DP and a P2 in speed,” said Mugglestone. “We don’t have the DP’s power, but we’re lighter weight and we have less drag, so we actually have the acceleration of a DP – but because we didn’t have a differential in the car, we haven’t been able to use it. The P2s are at the opposite end of the scale, with much better cornering ability than either the DP or us but more drag and less horsepower. If you break down the numbers, we’re actually closer to a DP. That’s why CTMP should suit the car, since we can use the straight line speed and keep momentum going.”

As the season continues, the DeltaWing team goal is simple: to maintain the delicate balance between performance, weight and reliability.

“The changes we’ve made will strengthen us for the remainder of the year,” said Keene, “and I expect to see the results of that starting this weekend. We’re looking forward to a good weekend, since fast, flowing tracks like CTMP are favorable to the DeltaWing. So getting to the finish is the priority and if we do that, I expect a good result.”

Katherine Legge joins a returning Andy Meyrick (coming off two Blancpain victories in the Bentley GT3) behind the wheel of the DeltaWing coupe at Canadian Tire Motorsports Park in Bowmanville, Ontario, Canada this weekend.

Toyota No. 8 car wins the 24 Hours of Le Mans for third consecutive year

24 Hours of Le Mans
JEAN-FRANCOIS MONIER/AFP via Getty Images
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LE MANS, France — Toyota Gazoo’s No. 8 car comfortably won the 24 Hours of Le Mans by five laps Sunday to secure a third straight victory in the prestigious endurance race.

It was also a third consecutive win for Swiss driver Sebastien Buemi and Japan’s Kazuki Nakajima driving. Brendon Hartley was the other driver, having replaced two-time Formula One champion Fernando Alonso.

Buemi and Hartley sat on the side of the car as Nakajima drove toward the podium. Hartley won for a second time after tasting success with the Porsche LMP Team in 2017 before an unhappy season in Formula One.

The Swiss team’s Rebellion No. 1 featured American driver Gustavo Menezes and Brazilian Bruno Senna – the nephew of late F1 great Ayrton Senna.

It finished one lap ahead of Toyota Gazoo’s No. 7, with Rebellion’s No. 3 finishing in fourth place.

For much of the race it looked like Toyota’s No. 7 would win after leading comfortably from pole position. But late into the night the car encountered an engine problem and the 30-minute stop in the stands proved costly.

The race was first held in 1923. A total of 252,500 spectators attended in 2019, but there were none this year when the race started three months late because of the novel coronavirus (COVID-19) pandemic.

“We miss the fans,” New Zealander Hartley said. “I look forward to seeing all the fans again.”

In other divisions:

United Autosports won the LMP2 division with the entry of Filipe Albuquerque, Paul Di Resta and Phil Hanson.

–In LMGTE Pro, the victory was claimed by Aston Martin Vantage AMR of Maxime Martin, Alex Lynn and Harry Tincknell (who drives for Mazda in the DPi division of IMSA).

–TF Sport won the LMGTE Am class.

The Toyota No. 7 took pole after former F1 driver Kamui Kobayashi narrowly edged out the Rebellion No. 1 team in qualifying.

In damp and humid conditions Mike Conway got away cleanly from the start, while Senna held off Buemi.

After nearly seven hours, Toyota’s No. 8 fell back after a 10-minute stop in the stands to fix a brake-cooling problem on Kazuki Nakajima’s car. Rebellion’s No. 1, driven by Frenchman Norman Nato, took advantage to move into second place behind Toyota’s No. 7.

Then came the decisive moment at 2:40 a.m. as the No. 7 – also featuring Argentine Jose Maria Lopez – encountered a turbo problem. When the car came back out it was back in fourth.

“We had a few problems early in the race,” Nakajima said. “Later they had a bigger issue than us.”

Rebellion’s No. 1 encountered a problem on the hood at around 9 a.m. and the change took six minutes, allowing the Rebellion No. 3 (Nathanael Berthon-Louis Deletraz-Romain Dumas) to close the gap.

It was becoming a tight battle between the two Rebellion cars behind Toyota’s No. 8.

At 12 p.m. Rebellion No. 3 with Dumas behind the wheel was only one second ahead of No. 1 driven by Menezes. Then both cars came in for a driver change with Deletraz swapping for Dumas on a lengthy stop, and Nato for Menezes as Rebellion No. 1 suddenly moved ahead of its team rival.

Dumas, a winner in 2016 with Porsche, appeared unhappy at the strategy decision to bring his car in first and the length of the stop. There were tense explanations in the team garage.

Colombian Tatiana Calderon, an F1 test driver with Alfa Romeo, was in the Richard Mille Racing Team in the LMP2 category. She was joined by German Sophia Florsch – an F3 driver – and Dutchwoman Beitske Visser. They placed ninth out of 24 in their category.