Peugeot 908 discussion

[Bentley03]

5 pages of detailed photos now on Endurance-Info.com.

Plenty for you to get your teeth into there, Mike!

[Bentley03]

Where's Knighty? Would like his opinion on V8 twin turbo vs V6 single turbo.

Knighty, are you out there mate?

[gwyllion]

The Audi V6 with exhaust in the middle sounds like a compromise dictated by the chassis/aero people. Peugeot again went all engine, with the best possible engine configuration (same cinder displacment as V12 and 90° angle for balance), and built the chassis around it. So my guess is that Peugeot probably has a more powerful engine.

[Bentley03]

Originally Posted by gwyllion

The Audi V6 with exhaust in the middle sounds like a compromise dictated by the chassis/aero people. Peugeot again went all engine, with the best possible engine configuration (same cinder displacment as V12 and 90° angle for balance), and built the chassis around it. So my guess is that Peugeot probably has a more powerful engine.

I'd agree, but how much more economical (if at all) is the Audi configuration likely to be? With the considerably reduced tank capacity, could fuel economy be Audi's trump card under the new regs.

[gwyllion]

Last year, the theory that the V10 TDI would have better fuel economy than the V12 HDI because of less cilinders, proved wrong.

[chernaudi]

At Le Mans and Paul Ricard, the R15 and the 908 had equal fuel mileage figures, and often, espeically later in the race when the Pugs had to push, the Audis often ran 1-2 more laps per stint.

In the ILMC events, it seems that especially at Silverstone that the HD aero on the R15's largely destroyed any fuel mileage advantage that they had earlier.

Maybe if the R18 is sleeker, it might gain it back, as it has a roof and lower body overall. And the R18 and the 908x have the same size air restrictors, so Peugeot's power advantage and straightline speed advantage might not be there anymore, and in theory, Audi and Peugeot should be on more equal footing.

Then again, the R15 got them there--for two races in '09 and on pace for Paul Ricard, Spa, PLM and Zhuhai last year, but Audi only won Sebring '09 in that period.

Problem is that for a given capacity, no matter the number of cylinders, the same fuel gets burned. I think that Audi's trump card might be that the R18 might do better at higher downforce circuits and may be as reliable as the 908x (that factor isn't known for both cars as of yet in race conditions), and that the R18 might be easier to repair than the 908x in the event of a mechanical/eletrical issue or after an accident if it follows the R8's modular philosophy.

[Victor_RO]

At Le Mans both cars yo-yo-ed between 12 and 13 laps per stint according to how they were driven. As for drag? Both cars will be optimised for as low drag as possible for the big event. Plus Peugeot will have some superiority in terms of the engine, simply because it has been running and being developed for longer. Also, both the old 908 and the R15 ran equal restrictors last year, and the Pug still had a top-end advantage in terms of engine power.

Originally Posted by chernaudi

Then again, the R15 got them there--for two races in '09 and on pace for Paul Ricard, Spa, PLM and Zhuhai last year, but Audi only won Sebring '09 in that period.

Coulda woulda shoulda, to quote Scott Pruett.

[Tim the Grey]

Are we sure Audi's set up WILL be less powerful than Peugeot's?

KNIGHTY!?!?!?!?

I don't know, but would like to, please.

[gwyllion]

Originally Posted by Victor_RO

Also, both the old 908 and the R15 ran equal restrictors last year, and the Pug still had a top-end advantage in terms of engine power.

The 908 had slightly bigger restrictors because of the air conditioner.

I have to agree that Peugeot's higher top speed and faster acceleration were only partially due to coupe shape and 6 speed gearbox. Peugeot clearly built a better engine than Audi, producing more power with same amount of injected diesel fuel.

The Peugeot engineers toke some radical design choices, most notably the steel pistons and titanium conrods.

[Victor_RO]

Originally Posted by gwyllion

The 908 had slightly bigger restrictors because of the air conditioner.

Wasn't that rule dumped for 2010 though?

[gwyllion]

No, the rule is dropped only for this year. See page 29 of http://www.mulsannescorner.com/2010LMP12.pdf

[Victor_RO]

Originally Posted by gwyllion

No, the rule is dropped only for this year. See page 29 of http://www.mulsannescorner.com/2010LMP12.pdf

Okay, thanks for that.

In any case, that means a ~1.6% difference in available air between the two engines. And the power advantage that the 908 had over the R15 couldn't have been only this small.

[gwyllion]

Another interview with Gene: http://www.autosport.com/news/report.php/id/89291

Apparently his crash during testing was huge:

Q. Can you talk about your crash in the new 908 at the Motorland Aragon circuit in Spain last year?

MG: I'm not sure how much I am allowed to say, but I can tell you I am lucky to be here. It was the biggest accident I have ever had in my career. There was a failure, the car went sideways and the car went up in the air. I spent a couple of nights in hospital and I wasn't right for a month. It took me a while to get back to fitness.

Q. Did you feel the affect of the new shark fin that's been designed to keep these cars on the road?

MG: This was a really high-speed accident at more than 300km/h [nearly 200mph]. The fin helped. It seemed the car went up slower than in the accident I had at Le Mans three years ago and then came down much faster, so it did work. But there is more to be done, I believe.

[NightStalk3r]

So the fins make the car hit the ground harder after it has taken off, nice one ACO, real safe!

[gwyllion]

Originally Posted by NightStalk3r

So the fins make the car hit the ground harder after it has taken off, nice one ACO, real safe!

Please read the interview with Nick Carpenter of Delta Motorsport, who did the FIA study on the fin, before making uneducated comments: http://www.mulsannescorner.com/newsjuly10.html

[WMUCarGuy]

Originally Posted by NightStalk3r

So the fins make the car hit the ground harder after it has taken off, nice one ACO, real safe!

I think he means that he didn't spend as much time in the air, not that he came down harder.

[chernaudi]

Originally Posted by Victor_RO

At Le Mans both cars yo-yo-ed between 12 and 13 laps per stint according to how they were driven. As for drag? Both cars will be optimised for as low drag as possible for the big event. Plus Peugeot will have some superiority in terms of the engine, simply because it has been running and being developed for longer. Also, both the old 908 and the R15 ran equal restrictors last year, and the Pug still had a top-end advantage in terms of engine power.



Coulda woulda shoulda, to quote Scott Pruett.

Closed LMP1s pre-2011 had a larger air restictor because of the AC system, which most never used. The ACO decided that based on the Corvette system, that the power losses are negligable, so dropped the break for the closed cars--from here on out, open and closed cars have to use the same restrictor size.

Either way, Audi knew that the 908s had a big straightline speed advantage, especially at Le Mans. Even if the R15 was the better downforce car, they lost what they gained by being slower down the straights and having inconsistant low speed grip. Hence why the R18 is a coupe and has wider front tires.

That being said, it seems that the 908 lacked low speed grip up front too, it's just that most of the time that they managed it better than Audi did.

But I do wonder about the "old" 908, in that it seemed that they lacked the speed in the dry over Audi that they often had, but in the wet they were competitive with Audi instead of their cornering being a series of accidents that didn't happen.

Could Peugeot have discarded the J-damper that was used on the 908 in '08 and '09, and found something that was a better ballance, and if so, would or wouldn't the 908x use the J-damper, or the R18 for that matter?

[NightStalk3r]

Originally Posted by gwyllion

Please read the interview with Nick Carpenter of Delta Motorsport, who did the FIA study on the fin, before making uneducated comments: http://www.mulsannescorner.com/newsjuly10.html

The FIA? is that the guys who run that F1 series that has pretty much done away with the fin for 2011?

[gwyllion]

Originally Posted by NightStalk3r

The FIA? is that the guys who run that F1 series that has pretty much done away with the fin for 2011?

I suggest you have a look at pictures of the new Red Bull RB7, which still features a shark fin.

I don't see the link with F1. FIA regulates a whole range of motorsport disciplines.

[NightStalk3r]

Originally Posted by gwyllion

I suggest you have a look at pictures of the new Red Bull RB7, which still features a shark fin.

I don't see the link with F1. FIA regulates a whole range of motorsport disciplines.

Exactly, 1 car of all the cars unveiled for 2011 has the fin all the other teams have done away with it, if it was such a big saftey advantage then the FIA would mandate them they dont therefor they obviously cant see much of an effect on saftey, and we have Gene as proof that they dont prevent the cars from getting airborne.

[Aysedasi]

That's a fairly substantial assumption to make based on what happened to Gene...

[Simmi]

And the F1 shark fins weren't introduced as a safety feature in the first place.

[NightStalk3r]

Originally Posted by Aysedasi

That's a fairly substantial assumption to make based on what happened to Gene...

I guess i missed something, i could have sworn they were introduced to prevent cars from getting airborne, and yet even with the fin the car got airborne.

[Audi Racer]

Guys atleast we know the new cars reach over 200mph. thats still alot of horsepower

[Audi Racer]

makes you wonder how much peugeot and audi are lying about their respective power numbers. Who knows if they are doing like 650.