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A Closer Look At The Two Oreca 07 Aero Packages

Just how much can you change on the default and Le Mans LMP2 aero packages?

With the teams having had plenty of time with the new LMP2 cars, DSC thought it would be interesting to to note how much work teams need to do each time they use their new bits of kit at new circuits, with little data, to get their setup right.

So, to get an insight into what tweaks are being made which many fans may not notice during a race weekend, DSC spoke to the lead engineer on the #21 DragonSpeed Oreca 07 Gibson, Leon Gutfreund, to find out what you can and can’t do with the new cars.

At last week’s ELMS meeting at Monza, DSC noted that DragonSpeed was sending its Oreca 07 out with two different front and rear sections during Free Practice, to work out which set up suits the Autodromo in the most efficient manner.

The team ran both low and high-downforce settings on the standard (non-Le Mans) bodywork throughout the first session, before coming to the conclusion that actually, with the 2017 Oreca, running it in a high-downforce set up, was best for the race.

“We compared the eight angles on the wing (by adjusting the flaps on the rear as shown above), and tried taking off the dive planes,” said Gutfreund. “There’s two on each side as standard, and you don’t have to used both of them, you can take one set off off, or both off. If you take them off it changes the balance of the car.

“When you do back to back setup changes during a session, you have to take care,” he continued. “It’s not just wings and dive planes that make a difference to the speed of car, any weight can make a difference to the lap time, so we actually topped off the fuel in between the runs to keep the same weight. We also needed to be wary because the tyres were degrading.

“If you adjust the ride height, that changes the drag too. The actual physical changes you can make are only the visible areas of downforce. There’s so many variables to the attitude of the car and the height of the car.

We used our spare sections during practice instead of changing on the fly because changing the wing takes five minutes, while bolting on a new rear end is 30 seconds

“You use the same driver to look at the two options, look at the data, listen to the driver, make a call on which is better and then put the gentleman driver in to see if he is comfortable.

“We used our spare sections during practice instead of changing on the fly because changing the wing takes five minutes, while bolting on a new rear end is 30 seconds. It saves time. So we prepared two sets to put on the car.”

On the front end, there’s four combinations available to teams. You can run without any dive planes, with the two lower ones, the two higher ones or all four (as the team did at Silverstone, pictured below).

The key is that there’s no regulations stating when you can make changes during the standard ELMS meetings, so you could change the set up of the car mid race if you wanted to.

The team then tried the combination they thought worked best with different angles to the rear wing. There’s eight angles you can choose from, with the addition of two gurneys, one on below the rear wing, and one sitting as a lip on the actual wing itself.

If you take the rear flap off there’s about four percent less or more drag, and with the front dive planes two or more percent downforce

“There’s four downforce and drag levels,” he explained to DSC. “If you take the rear flap off there’s about four percent less drag, and with the front dive planes two or more percent downforce. On the rear wing in particulate, you can adjust with the block that sets the angle in the middle, and the bits on the side which we call the banana which is on the ends (below). It sets the main angle and keeps the two parts together. There’s eight angles you can run, there’s quite a suite, and you can run any of those at any time.”

“There’s not much to actually gain in pure lap time by giving the car less downforce around Monza, because around a place like that you go faster down the straight, but it’s harder to drive through the corners. We were trying different things to learn something, and we did. Running a higher downforce set up didn’t make much difference to the top speed by running with a set of dive planes, so you run with the higher downforce package for Qualifying and the Race.

“It’s not as sophisticated as you might think, and ultimately, most teams end up making the same decisions in the end anyway. In FP1 everyone each weekend everyone is running different angles and dive plain configurations, but after Qualifying everyone was running the same dive plane configuration and wing angles.”

All this work had to be carried out, despite the fact that the 10star DragonSpeed team had run its Orecas at the pre-season ELMS Prologue at Monza earlier in the year. As Gutfreund explained to DSC, there’s a lot of differences, mainly the time of year.

Because of this, the Prologue was more of a chance for the drivers to get seat time, and the mechanics to practice working on the car in the garage, rather than an opportunity to prepare fully for the four-hour race later in the season. For instance, everyone at the race, used a single set of dive planes and at the test, the setups were more varied, the sister G-Drive by DragonSpeed Oreca circulating in the lowest-downforce setting possible, without any dive planes at all (below).

“It’s hard to take too much from the Prologue,” he revealed. “In fact, I preferred Paul Ricard, because there’s more corners, and variations.

“The reason why we couldn’t take too much from what we saw at the Prologue is because of the track temperature. It was a key factor, because it was so hot in race week we had to use the hard tyres, at the test it was cooler and we used the medium tyres. At the test everyone was on mediums and then the sun came out on the second day and everyone gradually switched to hard.”

Then there’s the Le Mans aero package, which DragonSpeed has yet to test. The Le Mans aero for the cars is a simpler package, for which the team’s have less decisions to make and fewer combinations to try during pre-race running.

The Le Mans package is somewhat simplified because it’s all about low-drag

“The Le Mans package is somewhat simplified because it’s all about low-drag. This standard package for the rest of the season is more flexible because it has to cope with the slower and faster circuits. The Le Mans package is compulsory for Le Mans, and not possible for anywhere else.

“Le Mans is a wide open track, the chicanes are square, and because of that trying to drive at Monza with Le Mans aero would be awful, which is why only a couple of teams tried it at the Prologue.

“The Le Mans aero for the Oreca has only just become available too, so it wasn’t really possible. There’s not many in existence either, so our first run with it will probably be the Le Mans Test Day.

“What I know is that on the front end, there will be one set of dive planes, which you need to run, so there’s no changes to be made there, and on the rear, the little gurney underneath the rear-wing will be raised by 10 centimetres or so, effectively creating a small wing (see above).

“I have seen it, but haven’t run it.”