2010 24 Hours of Le Mans (June 12-13)

[henk4]

I was kinda lost in the original line of the questioning so I am not answering that properly I guess. The fueling and the tub was the fix parameter for the practical purpose of ALMS racing. Aero-wise the car was made to build a lot of downforce for the tighter North American tracks. As Mulsanne's corner's conjecture explained, the car was designed with certain kind of lift to drag ratio in mind, with a set amount of downforce as a goal. I guess that was a conscious decision on Audi's part when they started the R15 project. However when it was decided that R15 will not race in ALMS, some of those design direction no longer made sense. At Le Mans when you trim the downforce off, they weren't able to proportionally shed off drag so as a result they suffered for it....

Thats one part of it, and another I think was just the car was simply not used enough so they don't have enough understanding of it.....

that is an explanation I can live with, and it not the first time that I see/hear your last sentence

[Chernaudi]

That's what I've been saying all along. Audi did the opposite of conventional race car design. They targeted a downforce number and let the drag be what it be, instead of as on the R8 and R10 of targeting a drag number and adding downforce for the ALMS/LMS tracks.

As Audi found out, it's easier to to add downforce than to take it away, hence the channel concept was basically not worth it. Of course, Audi didn't think they wouldn't run the ALMS more than they did in '09 back in mid-late 2007 when the inital design of the R15 began. The R15 Plus is what Audi should've aimed for from the beginning, and if the channel concept didn't side track Audi, the R15 would've been stronger at Le Mans in terms of single lap pace than it was.

However, if it wasn't for the R15's initial reliablity problems, Audi might not have had such a reliable car this year.

[RacingManiac]

I think if R15 had kept its initial design but have had real racing before LM, they might still be competitive back in 2009.....

R10 was much slower than 908 and yet it always kept it honest.....Audi knew that car well, the drivers know that car well and they were able to run it to the full potential. R15 was basically a still-born the whole season in 2009.

[henk4]

That's what I've been saying all along. Audi did the opposite of conventional race car design. They targeted a downforce number and let the drag be what it be, instead of as on the R8 and R10 of targeting a drag number and adding downforce for the ALMS/LMS tracks.

Right, but that is something else than saying it was designed for the twisty ALMS tracks. Apparently Audi had the idea that they could shoot two bears with one bullit, by designing a car that could do the twisties and could be adapted suitably enough for LeMans. My point is that Le Mans was still their main target, and they thought they could reach that by designing the car in the way they did. They eventually succeeded, but still not because of the car's intrinsic capabilities, but because of an as yet unexplained lack of reliability of the competition.

[Chernaudi]

Still, the R15+ was much faster at LM than the original car was, and it closed the gap to Peugeot. In '09, the R15 started off 3-4 seconds a lap slower than the Pugs. In '10, the R15+ cut that to 1-3 seconds a lap on average, and the Peugeots had to hammer their cars to viritual self-destruction to keep that gap, let alone run qualifying lap speeds that were again only 2 seconds faster than each Audis' fastest race lap.

The R15+ is a better car than the R15 and if Audi didn't sidetrack themselves with the ineffective-for-Le Mans channel concept, they'd have improved their pace over this year.

The only time a car was consistantly 1-3 seconds a lap faster than any Audi that beat them at Le Mans that didn't involve the flawed early R15 was the Bentley Speed 8, which as we all know was a car built with Audi Sport money and resources and used an Audi engine in it.

Besides, I think that the R15+ ultimately rattled Peugeot a bit. Audi were a tad surprised that Peugeot still held a big top speed advantage, but I think Peugeot also were surprised that Audi had closed the gap as much as they did over '09, hence the "checkers or wreckers" orders from Quesnel and the engine failures.

[henk4]

Still, the R15+ was much faster at LM than the original car was, and it closed the gap to Peugeot. In '09, the R15 started off 3-4 seconds a lap slower than the Pugs. In '10, the R15+ cut that to 1-3 seconds a lap on average, and the Peugeots had to hammer their cars to viritual self-destruction to keep that gap, let alone run qualifying lap speeds that were again only 2 seconds faster than each Audis' fastest race lap.

The R15+ is a better car than the R15 and if Audi didn't sidetrack themselves with the ineffective-for-Le Mans channel concept, they'd have improved their pace over this year.

The only time a car was consistantly 1-3 seconds a lap faster than any Audi that beat them at Le Mans that didn't involve the flawed early R15 was the Bentley Speed 8, which as we all know was a car built with Audi Sport money and resources and used an Audi engine in it.

Besides, I think that the R15+ ultimately rattled Peugeot a bit. Audi were a tad surprised that Peugeot still held a big top speed advantage, but I think Peugeot also were surprised that Audi had closed the gap as much as they did over '09, hence the "checkers or wreckers" orders from Quesnel and the engine failures.

until we know what actually caused the Peugeot problems all suggestions that they were harassed by Audi towards destruction is only speculation.....it could well be one of those infamous 10 cents parts of which a faulty production run was used.

[Chernaudi]

$.10 parts don't cause 5.5 diesel V12s to explode at random in the way the Pug's engines let them down. When the #2 908 expired, Montangy was pushing, and running 3:20s-3:22s every lap at that stage was pushing it, as he had a lap in a half lead over the 2 R15s behind him. However, the #9 and #8 Audis were running 3:22s consistantly during Montangy's last stint as well.

The #1 908 was running 3:19s-3:21s, while agian the Audis were running 3:21-3:22 times. Davidson strangled the 908 during his stint in the car, and Wurz had to hammer it as well to have any chance of catching the #9 Audi when it went up.

And the #4 Oreca 908 was running 3:19s and 3:20s to try and run down the #7 Audi to challenge for a podium, and it expired.

What did all 3 failures have in common? The Audis were lapping within 1-2 seconds of the Peugeots at the time of the failures, and all 3 engine failures happened soon after scheduled green flag pit stops(Montangy's Pug blew up immediately after his stop)

I've been asking on Mulsanne's Corner's Facebook page about the failures, and the general consensus is that it was massive piston failures that cased the demise of the Pugs. But how do you melt a piston in a diesel, since after all diesels rely on detonation for ignition? Espcially when it's been rumored that Mahle made speical steel(instead of aluminum) pistons for the 908s at Peugeot's request.

I think the failures were performance related, as the Peugeots ran like a sprint race, especially the cars that had troubles during the night. But then again, Andre Lotterer ran a lap that would've had him qualified 5th and was nearly half a second faster than Rocky's qualifying time, and Loic Duval in the Oreca Pug ran a time that would've won him the pole this year within a lap or two of his 908 flaming out.

I just think that the Peugeots were being pushed to the limit in an attempt to build a gap in case they had a problem, or to make up for lost time. Just the fact that they still had typical minor problems that they've always had while the Audi's exibited R8-like bullet proof reliablity I think speaks for the fact that no matter how much testing one does, it can only at best account for 99% of what may happen, and that leaves that 1% of uncertianty.

The Pugs have never been the most reliable of racing cars because of their sprint race nature. Audi went that same route with the early R15, and it bit them just as hard as it did Peugeot in the past. Audi went back to basics with the 2010 R15, and it worked.

It may've been just bad luck that all the Pugs DNF'ed at Le Mans, but you don't have 3 nearly identical engine failures in today's day and age because of a bad batch of parts like what happened sometimes 10 years ago. It may've been an engine mapping flaw or just that Peugeot never pushed 100% as hard in testing. But the fact that Peugeot couldn't build the gap over Audi like they did last year wasn't a good sign, and neither was Audi being able to match the Pugs laptime to within a second or two most of the race.

[henk4]

you are proving my point...pure speculation
and saying that the Pugs were more designed for sprint races ("sprint race nature") is rather close to nonsense...THEY never had ALMS in mind....
Your suggestion that the Peugeots were pushing is a bit easy. You can also say that they were keeping up the speeds that they could maintain for 24 hours during the simulation tests. But indeed if pushing was the cause of the damage, the better strategy would have been to stay with the Audi until the final hour and then run away from them, which they managed so easily.....
we will just have to wait until Peugeot gives out an official explanation, or alternatively until people close to them will get some information. May be they gambled on something which was not properly tested, which could be pistons, but on the other hand, what would have caused the flames, as diesel fuel is not prone to ignite easily. For the time being, let's wait. At least it is clear when they found the cause in one car, they don't have to search long in the other cars.

[Chernaudi]

At ten-tenths.com, I asked in the racing technology section, and again no solid answers but a new theory emerged: turbocharger failure. One post said that the 908s turbos ran on engine oil pressue, hence an oil pump failure could cause the turbos to seize and break, sending metal into the cylinders. I've never heard of Peugeot having turbo problems, at least that major. However, in '07, they did have oil pressure problems with their engines at Le Mans and maybe one other LMS round.

If a turbocharger failed, that would explain why only one bank of the engine showed flames and smoke, and why the fire-any diesel fuel or engine oil that contacts that cherry-red hot turbo would go up like hydrogen exposed to an open flame, as that liquid would vaporize almost immediately. It also my explain the oil hemmoraging, as the holed piston might have sustained a bent connecting rod, and the pistor or broken rod would've tunneled out the block or sump pan.

Whatever caused the issue, Peugeot has been mum on the issue, and it's been nearly a week since Le Mans. And whatever the issue, it seems that Peugeot is shocked and baffled by it, as normally such things would show up in a 30 hour test if they cars were hammered. Which is why I said that the Audi pace may've pushed Peugeot management to pull out all the stops, espeically as their cars had trouble, and it was just a step too far-why run qualifying laps 1-3 seconds faster than the Audis when a equal race pace likely would've gotten the job done?

[faksta]

Here are some of mine. Only Group C yet, though - I still need to deal with the actual race shots. Gr.C race has gone mostly in attempts to adjust a new camera, so don't judge too strong

The fence was very annoying as well

[faksta]

Gr.C #2

[faksta]

Gr.C #3

[faksta]

Gr.C #4

[faksta]

Gr.C #5

[faksta]

Gr.C #6 and last.