Audi LMP1 Discussion

[Simmi]

Originally Posted by CTD

Very interesting! - almost sounds like, a Petrol! (which it of course isn't)
Didn't the Peugeot engines have more sound in 2010, in the same way as the Audi does?

Yeah the Pug did sound different in its final iteration. The Audi seems to sound more raspy though. Not a bad sound. The 908 was a bit more like a tractor.

http://www.youtube.com/watch?v=DZYxASTvTrQ

[Victor_RO]

Originally Posted by Simmi

Yeah the Pug did sound different in its final iteration. The Audi seems to sound more raspy though. Not a bad sound. The 908 was a bit more like a tractor.

http://www.youtube.com/watch?v=DZYxASTvTrQ

He meant the 2010 908 (i.e. the last year of the big V12), and that one was clearly audible and not as tractor-ish as the V8. http://www.youtube.com/watch?v=OE5s72Td18k

[CTD]

Originally Posted by Simmi

Yeah the Pug did sound different in its final iteration. The Audi seems to sound more raspy though. Not a bad sound. The 908 was a bit more like a tractor.

http://www.youtube.com/watch?v=DZYxASTvTrQ

I'm thinking the gearing has been changed at lower speeds so it revs higher to compensate for the Hybrid Lag?

[TF110]

I heard wooshing sounds and it pushing through the air. The circuit was windy as evidenced by his hair. Maybe the exhaust is changed somewhat or they're running more power through the hybrid.

[MitchZ06]

I doubt wind would change a quiet engine note to a loud raspy one. Sounds awesome now!

[TF110]

Originally Posted by MitchZ06

I doubt wind would change a quiet engine note to a loud raspy one. Sounds awesome now!

Never said that. I said the track was windy, so it pushing through the air could be more pronounced.

[Mal]

Definitely sounded different .. but an element of that would be the circuit as it is partly surrounded by buildings which would cause some echo

[chernaudi]

Numerous new R18 photos from Yas Marina test up on the Audi Sport International FB page (I don't know of where else they're at, but considering that Mulsanne' Corner FB page has a link to them, you can bet that Mike will be analyzing them soon), which raises the question: How do they expect to get the rear deck off the car, since it seems that the outer rear wing endplate is hardwired into the rear bodywork, and I can't really see any parting lines separating body panels. Also of note is that the outer endplate has significantly smaller surface area than the main endplate.

There's also a video of the R18 there, too:

http://www.facebook.com/AudiSportInternational

It also seems that Audi tested a 2012 LM spec R18 at Yas Marina along with a 2013 sprint race spec R18.

[Pandamasque]

Originally Posted by chernaudi

http://www.facebook.com/AudiSportInternational

It's quite a bit louder than I expected...

[NelisB]

Originally Posted by Pandamasque

It's quite a bit louder than I expected...

I even hear a blow off valve. It's ofcourse possible that the car sounds louder as there are no other cars/petrol engined v8 scream machines near it.
I expect the car to be as silent as last year. It's just un-audi-like to hear the sound of the car.

[MitchZ06]

The R8 was loud, the R8 LMS is loud, I'd love a loud R18. That turbo whoosh and gruff sound is awesome

[gwyllion]

There seems to be a flash light on top of the roof air intake, which is not present on the endurance-info pictures:


Also note that the #1 and #2 nose appear slightly different, especially in the area where the cover panel connects on the inside of the front fender.

[NelisB]

Originally Posted by gwyllion

There seems to be a flash light on top of the roof air intake, which is not present on the endurance-info pictures:


Also note that the #1 and #2 nose appear slightly different, especially in the area where the cover panel connects on the inside of the front fender.

The top picture is to dark to get any real details out of it. I could ofcourse boost the exposure but it's copyrighted :').

[TF110]

You can see it clearer in this picture of the #2

[chernaudi]

Looks like some kind of camera--if you look at the front of it, it has an item that resembles the revolving lenses used on F1 and NASCAR onboards.

[MJones94]

Leo Parente - the host of the Drive Network's Shakedown episodes - mentioned in a recent video that the 2013 R18 had a new turbo (Although I cannot remember which particular video ).

Perhaps this would explain the change in the sound of the car?

[gwyllion]

More pictures from the second (?) Abu Dhabi test: http://www.facebook.com/media/set/?s...26773594108805

[chernaudi]

Those look like screen caps from the video that was posted in this thread, so sadly, nothing too "new" really.

Of course, there's the fact (though not apparent in this video) that Audi had a 2013 car (presumably in sprint bodywork, featuring the new endplate adaptation), and a 2012 LM spec car. Of course, Audi expect to run a 2013 car, and (I assume) some 2012/13 hybrid spec car (2012 car with some 2013 parts) at Sebring. And of course, we don't know if Audi's LM and Sprint packages will differ or how, and probably not until they do more testing with the 2013 car with a low downforce package on it.

Of course, there's all kinds of fodder for debate at the Mulsanne's Corner FB page over the new R18's turbocharger system (there are reports that Audi have altered their system for '13 in some why, but that's rumor for right now--it mostly relates to rumors of Audi running some type of turbo-compounding system for their hybrid stuff) and even the R18 adopting a "blown diffuser" of some type, which is unlikely; such a thing is probably (obviously) frowned upon by the rules, and with the positioning of the R18's exhaust pipe, any such gains would be minimal in the real world.

[TF110]

Blown diffusers are forbidden in LMPs. The gain from them probably wouldn't be anything major anyway. IMO it'd be better to run exhaust over the rear body panels, almost like F1 with their exhausts 'blowing the floor'.

[gwyllion]

In earlier discussions, it has been pointed out that the exhaust gasses of a low revving diesel engine are not fast enough to be used for aerodynamic gains.

F1 engines run at 18000 rpm, whereas LMP1 diesel engines only rev to 5000 rpm. That is a huge difference.

Furthermore, a lot of the kinetic energy of the exhaust gasses is consumed by the turbocharger.

[chernaudi]

As I mentioned, any gains would be minimal, probably only detectable in a wind tunnel, and probably not detectable at all from lap times or the seat of a driver's pants.

It should also be remembered that the rear diffusers are basically spec on current LMP cars--there's very few things under the current rules that are allowable that have any marked difference, primarily that there's a choice between two (total) or no strakes in the diffuser sections, and there's some places where maintenance hatches can be located, but that's limited to one per side, and a hole for the rear air jack, which on most cars is probably in the boat prow section. It's one of those deals where if it's not mentioned by the rules, it's implied to be illegal it seems. Of course, Audi and Toyota were tinkering with their endplate extensions last year (Toyota raced theirs, Audi tested theirs in a wind tunnel in case some rules clarfication did deem them to be legal) in an area where most though the same exact thing--the wording of the rules implied such an item to be illegal.

However, I do think that the rear diffuser is an area where the ACO/FIA really don't want teams to mess with outside of the parameters that they set forth. Even if there were EBD's in the LMP900/675 days of non spec rear diffusers, any benefits would be minimal--were talking 7000-8500 RPM maxes for most engines, the concept wasn't well known back then for sure, and Audi's 3.6 V8, like all their TDI engines, was turbocharged, and turbos break up and slow down soundwaves, which makes the engine quieter--and the exhaust flow muddled (which would be a bad thing aside from that engine exhaust being put to work to make "free" horsepower).

There are probably some residual effects of the exhaust blowing over the rear diffuser's airflow, but you'd need a wind tunnel to detect them, and it's definitely not the game changer it was in F1 for quite a while.

[chernaudi]

Also, from Mulsanne's Corner FB page, it's now suspected that the device mounted on the engine intake that looked like a camera is, well, a camera. However, it's thought to be related to the rear facing camera, but beyond that and rumors that it's to activate certain sensors (similar to the Audi Side Assist blind spot detector and other similar blind spot detection devices on most new passenger cars), it's purpose isn't clear.

[gwyllion]

Personally I would expect a blind spot sensor/radar system to be mounted on the wheel fenders, not on the roof.

Anyway, Mike tweeted that it is a front facing camera.

Originally Posted by @mulsannescorner

@RacecarEngineer @MyNameIsNigel @JAGLeMans audi sources tell me its a forward camera similar to their rear system. Will race it this year

source: https://twitter.com/mulsannescorner/...27749435961345

[MyNameIsNigel]

Originally Posted by gwyllion

Personally I would expect a blind spot sensor/radar system to be mounted on the wheel fenders, not on the roof.

Anyway, Mike tweeted that it is a front facing camera.
source: https://twitter.com/mulsannescorner/...27749435961345

Hi guys,

I have been browsing though this forum for a file now and have just decided to join (yes this is my first post ). I hope you do not mind if I join this discussion. That's what this forum is about isn't it ?

I wanted to reflect on the device sitting on top of the air intake of the R18 last seen testing at Yas Marina after having already exchanged some words and ideas with Mike and others on this subject via Twitter and FB.

I suspect this device is not a camera device in the true sense as I doubt Audi is contemplating to provide a (further) video image of what is happening at the front, in addition to the existing video feed from the rear-vision camera. That would create too much distraction for the driver IMO. It could theoretically be a camera with some clever image processing ability to detect the proximity of objects at the front, but this appear to be a far too complex solution for racing applications.

I rather believe that the device is some sort of proximity sensor similar to those used in adaptive cruise control or side assist (blind spot detection) systems. As a matter of fact, my first impression was that this device looked very similar to motion sensing systems as typically used in home security alarms .

Mounting of sensors on the fenders directly could be an option (and who knows additional sensors might also be used by Audi in addition to the upper one), but this could potentially be problematic in terms of reliability and exchangeability of the frontal part. Audi has already faced undesired issues with the operation and reliability of the LED headlights.

In any event, while it's an interesting subject of discussion and speculation, I am more curious (and I trust many of you are also) to understand what is happening under the skin of the R18 and have further explanations as to the changes apparently made by Audi on the engine, turbo and/or exhaust side. The noticeably different sound of the R18 running at Yas Marina has fuelled my curiosity.

[Pandamasque]

...or it could just be a quick GoPro shoot for an upcoming promo video

Welcome to the forum, Nigel.