Audi LMP1 Discussion

[Lola T70]

open face helmets are not homologated.

[chernaudi]

NASCAR banned open faced helmets at the end of their 2004 season, and it seems that the ACO followed suit for closed cars, especially when only F1 homologated helmets from Arai, Bell, and Shuberth are endorsed by IMSA and the ACO.

And aside from the visor tinting, I don't see how the helmets impact visibility either, aside from Dindo's issue at PLM. I think that the curved windshields--even the Pug's "optically flat" windshield--and the anti-glare blacked out areas are the main culprits aside from the roof itself. I think that many of Audi's drivers with GT experience will help them there, though after a while it seemed that most of Pug's drivers got used to it.

[NightStalk3r]

Strange that the ACO dont allow open faced helmets' the FIA allowed them in FIA GT, Manu Collard always wore one.

[Ultimo]

Any idea what the V angle of the V6 in the R18 is?

I am far from an automotive engineer, so a number does not instantly pop into my head.

As I recall, old F1 V6s were more obtuse than the common road car 60 degrees for a lower centre of gravity.

[Audi Racer]

120 degrees

[chernaudi]

The Audi V6 is either 90 or 120 deg depending on who you ask. We won't know until we see the engine, though, but those are the two most likely V angles.

[Tim the Grey]

I would expect 120, to keep deck height low, lower COG, take advantage of the wider LMP1 tub shape, etc, etc, etc.
If the 'turbo in the vee' idea is right, then 120 again wins, as there's more room to breathe in there.

Now, if there's 2 turbos, life gets interesting! Although Porsche's 962 carried them outboard of the flat 6. Keep the weight down low.

[fieldodreams79]

Originally Posted by Tim the Grey

Now, if there's 2 turbos, life gets interesting! Although Porsche's 962 carried them outboard of the flat 6. Keep the weight down low.

Can you explain for the mechanical idiots in the crowd?
I understand wanting to keep weight low but....

[MulsanneMike]

Originally Posted by fieldodreams79

Can you explain for the mechanical idiots in the crowd?
I understand wanting to keep weight low but....

Well if Audi has gone and placed the turbo in the center of the V, even at 120 degrees, it becomes a packaging issue if they have more than one put there. But looking at the roof inlet, there just simply doesn't seem to be enough cross sectional area to feed two turbos. So I'm inclined to believe it's one, possibly located within the V, feed by the roof, and a 120 degree block angle to push mass lower.

But let's entertain one more location, in the bellhousing. For years Champ Cars, when they were turbo, put their single turbo in the bellhousing. This would allow the turbo to be low from a CG standpoint.

[nasdriv87]

[fiend540]

Originally Posted by MulsanneMike

But let's entertain one more location, in the bellhousing. For years Champ Cars, when they were turbo, put their single turbo in the bellhousing. This would allow the turbo to be low from a CG standpoint.

I know its a little OT but this is interesting, anyone have any pictures of a setup like this?

[carsten66]

Originally Posted by fiend540

I know its a little OT but this is interesting, anyone have any pictures of a setup like this?

http://www.howstuffworks.com/champ-car.htm/printable

scroll down to the engine descriptions...

[benjabulle]

Originally Posted by fiend540

I know its a little OT but this is interesting, anyone have any pictures of a setup like this?

here :
http://www.gurneyflap.com/Resources/HC6979.jpg

and the other side :

http://www.gurneyflap.com/Resources/DSC_6468.jpg

[benjabulle]

the french journalist who talked about the turbos inside the V and the exhaust located where you know was right for the latter, he learnt it from someone working with Audi, he must be right also for the turbos.

[MulsanneMike]

Something a little more relevant to sportscars:

http://www.mulsannescorner.com/nasamaxdm139-4.html

[CTD]

Having a turbo inside the V, doesn't that create a lot of heat?. Heat you normally would try distribute over the whole car, instead of having it centered at one, very hot place!?.
If it does, it must create some reliability issues, or require a lot of cooling..

[Tim the Grey]

Single turbo, then the most likely place is in the vee, or just behind it, over the gearbox. I don't see enough body height behind the engine for it to be there, so I expect in the vee.
Oh, and you need plumbing asshort as possible, to minimise the lag all turbos have.

Errr? Is SUPERcharging allowed? THAT could explain things... Extra length of a V6, for one.

[fieldodreams79]

Thanks for the info Mike and others.

Wouldn't a supercharger weigh a bit more than a turbo?

[Tim the Grey]

I think it depends on what/how it is engineered.
I suspect it could be done in Carbon, so end up MUCH lighter. Especially a Rootes type Blower. If that would work OK with a diesel. Certainly S/C is better at low revs. AND no lag, as it's engine driven.

Hmmm. Where's Knighty when you need him? I need a Diesel Engine Knowledge Base...

[EverOne]

I'm afraid Audi need 2 LeMans editions to make this car a winner. I think don't go with this car at 12H of Sebring is an error. They can collect tons information in a 12H race and make understand better the car and give some experience on how to work with closed coupe in real situations.
Hope Peugeot don't complain about R15++ like last year

[Tim Northcutt]

Originally Posted by fieldodreams79

Thanks for the info Mike and others.

Wouldn't a supercharger weigh a bit more than a turbo?

Not sure about the weight, but with the exception of a twin-Lysholm type supercharger, there is too much parasitic drain as the pressure and speeds increase due to the drag caused by the belts to spin the blower.

It's not as efficient as a turbo for that reason, although I do agree that it reduces the lag...however, most turbos now have the electronics adapted to them so that the turbine can keep the pressure up and you don't get the lag when throttling up from a slow corner, as an example.

That's why they make the "whizzing" sound when they are braking going into a corner...that's the turbo spooling to keep the pressure up.

[broadrun96]

I thought that was the main reason for a turbo over a blower in most applications, it takes away too much hp. I saw in the specs for a blower that one of the SpikeTV car shows installed that it took 125 hp to power the blower to make an additional 200, but the torque advantage made it worthwhile for a drag race installation. Not sure the diesel would benefit from the additional torque. Most of the supercharged diesel stuff I've seen online uses an electric supercharger to drive the turbo at low engine revs to make it more efficient, although I'm guessing Audi could do the same work with variable vanes and engine management software.

[chernaudi]

For those who wonder about turbo lag, remember that Garrett made VTG turbos for Audi for the R15 last year, and they worked fine. It wouldn't make much sense for Audi to run a single turbo--or even twin turbos--and discard that concept.

[chernaudi]

I would've edited this, but I got a message that the editing function timed out. So my applogies.

I though of this when I was thinking about the 2011 revisions to the Audi R15.

Does anyone think that the R18 will ultimately run the flat flaps in the nose like the R15 did last year for rules compliance, or does the diffuser being so aggressive and the actual front bodywork mask the questionable suspension parts? And where would the front brake ducts be? I'd imagine in about the same place as the R15, but it seems that the front bodywork and the diffuser obscure them from view, at least in Audi's photos of the car.

[The Badger]

I wouldnt think they would be runnin flaps at all , to cover any suspension bits ..... I would expect that from design that all the regs have been met ..... with respect to diveplanes , I expect they will differ from track to track .

Have I picked you up right ?