Mulsanne's Corner

Petit Le Mans 2009

All news content copyright Michael J. Fuller, unless otherwise noted

>>Don't forget to check out the Petit Le Mans photo gallery.

Petit Le Mans news:

Acura ARX-02a, Petit Le Mans 2009>>Speaking to Nick Wirth on Friday in the paddock, he was excited with the prospects of a wet race and he got his wish.  Unfortunately it still didn't play into the ARX-02a's hands.  There are those on the teams that feel the wide front tire concept simply hasn't worked.

We also spoke briefly about the Scott Sharp incident.  Wirth mentioned that everything was destroyed in the accident, "...even things like the battery box were destroyed."  The replacement tub was the 3rd chassis, and more notably, the only replacement chassis.  There are no others.

After their rebuild, Highcroft "cribbed" their chassis setup from De Ferran.  Apparently that's been the nature of the relationship all season, no competitive barriers between the organizations.

Which leads us to what we're hearing about the future of the Acura program.  It is growing less likely that we'll see Acura return (Gordon Kirby has already said Acura is done).  We understand HPD staff has been let go and we also understand that since about mid-season the HPD effort has had it's budget cut such that there are no spares on the shelves, everything is made to order from Wirth Research with a 6 week delivery time.  Has Acura already made a decision?  It's looking likely and it won't be the one we'd like to see.

>>Audi Motorsports head Wolfgang Ullrich was heard over the race track PA system talking with Radio Le Mans about the future of the Audi R15, and it was interesting to hear him mention the hold up with the ACO over the future regulations might cause pause for Audi to continue forward.  At very least it was, in his words, "...frustrating".  Completely understandable considering, as mentioned on these pages, the ACO draft regulations for 2010 face us with regulation changes for next year in the face of major changes for 2011 which doesn't make an ounce of sense.  But at the same time we understand that in all actuality Audi is well into the design of the R15's successor ("successor" as a 2010 update of the R15 or a true 2011 car we're unsure--but we can imagine both are underway) such that Audi Motorsports was operating with a skeleton crew at Petit; most of their engineers were back in Germany working away on the new car.  

>>A Michelin engineer was overheard confirming that Audi's issue at Le Mans this year were tire and downforce related.  Apparently the R15 generates significant downforce and a factor fold more than the Peugeot 908 which could nearly triple stint its tires at Le Mans.

>>We're told the ECO Radical tipped the scales into the 4-digits, i.e., well past the 900 kgs minimum.  They were a non-starter due to over-heating concerns.  Ironic considering the ambients on race day were a good 15 degrees below what had been seen throughout the week.

Check out Race Car Engineering's Acura ARX-02a and Audi R15 articles

>>It was another rainy day at Road Atlanta.  Drizzle persisted off and on though fortunately there wasn't the downpours associated with yesterday.  All of the prototypes present (Acura, Audi, Autocon, Drayson Lola, Oreca-Courage), barring Peugeot, made it out on track today.   
Audi R15, Petit Le Mans 2009>>This week the Audi is running the revised specification that the car raced in at Le Mans this year.  Here we see the revised engine cover.  The revisions to the rear engine cover  were apparently as a direct result of a request from the ACO.
Audi R15, Petit Le Mans 2009>>Here's the engine cover as Audi raced at Sebring this year.
Audi R15, Petit Le Mans 2009>>The nose vent exit is reduced, again, as raced at Le Mans this year.

Interestingly, one of Audi's issue at Le Mans this year was a result of the downforce load the car was carrying and the Michelin tire's inability to cope with those loads.  This was a known issue ahead of the race and much time and effort was put into finding a solution.  Ultimately, given the short time frames (8 weeks before the race), this led to a compromise in the car's setup.  In order to reduce front load the chassis was raked nose up.  This led to the third spring element to be fully packed out with bump rubbers, effectively compromising grip and traction in the critical areas of the track (Porsche curves, Ford chicane).  

In addition to the tire issue, it is our understanding that the R15 was also simply carrying too much drag for Le Mans.  Apparently the ducts that channel air through the rear of the car were generating too much drag for downforce gained.  The suspension shrouds were an attempt to mitigate this but their effects were negligible and the shrouds were effectively invisible from a drag reduction standpoint, hence they were on (Sebring, one car ran them the other didn't) and then off the car (Le Mans and now Petit).

At the moment the R15 is being revised for 2010 and the Petit Le Mans is being considered a post-Le Mans test session with the revised 2010 car in mind.
Oreca Courage, Petit Le Mans 2009>>This is our first close up look at the Oreca 01 AIM.  This is a shot of the rear diffuser strake, notice the cut outs.
Oreca Courage, Petit Le Mans 2009>>Full louvers but for one for the Oreca at Road Atlanta.
>>Ok, so I was a little overly critical of the Eco Radical effort yesterday.  In fairness the car seems much better turned out than the last time I saw the car at Sebring in 2008.  Recall then ( 3.19.08 entry) that the rear wheels weren't even centered in the wheel wells; clearly that car never was going to race anywhere.  Well much to their credit, the diesel Radical was out turning laps today (and yesterday), even in the wet.



>>Today's running at Road Atlanta in preparation for the Petit Le Mans this coming weekend was effectively washed out and culminated in a gully washer just after noon time.  IMSA canceled running as clay was washing onto the track, the paddock, pit lane, etc., etc.
>>Teams used the time to set up and simply catch up on car maintenance.  Drayson had their new Lola to bits.    
Audi R15, Petit Le Mans 2009>>Audi were working away.  It's good to see them back.  The R15 is in Le Mans specification but Road Atlanta trim (downforce levels).  So essentially that means all the non-circuit specific modifications we saw on the Audi (turbo intake, revised rear wing endplate mounts, air vent behind front wheel trailing edge, etc.) are on the car this week.
>>The Eco Radical SR10 has arrived.  Ian Dawson was seen looking over the details.  We understand they are slated to run through the scrutineering line on Wednesday at 11:40am.  Is it being cynical in pointing out they will be one of the last teams to run through the tech line?
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ęCopyright 2009, Michael J. Fuller