Audi LMP1 Discussion

[FstrthnU]

Motorsport posted a comparison of the Audi R18 TDI and Ultra http://www.youtube.com/watch?v=yObpO...layer_embedded

[Adam43]

750kg? It could race in the 1930s GP!

[Adam43]

Originally Posted by chernaudi

... Audi's machines being faster in the Porsche Curves.

I believe that is three fingers for any one playing the drinking game.

[deggis]

Get it?

[henk4]

The Auto Motor und sport article states that it was never more difficult to forecast the outcome of the 24 Hour race. It was never more easy, Audi will win. I have a bet with andrew Cotton that the difference of the winner after 24 with the first non-audi will be over 15 laps....
And Gwyllion, thanks for calling my shot of the front suspension the best so far, and yes there are two electric motors, and we guessed that the thing prominently sitting in the middle is part of the electric power steering. For the Ultra it can be located in the spot of the electric motors.
What we saw on times last sunday was not the 3 seconds difference that Lola calculated, but the sandbags could once more have played a role.

[manthey]

Originally Posted by Adam43

750kg? It could race in the 1930s GP!

ok f1 have less weight but consider that spa pole lmp1 was not so distant from the time of the last(slowest) F1 car

[gwyllion]

Originally Posted by henk4

And Gwyllion, thanks for calling my shot of the front suspension the best so far, and yes there are two electric motors, and we guessed that the thing prominently sitting in the middle is part of the electric power steering. For the Ultra it can be located in the spot of the electric motors.

On these two pictures you can see the difference between the ultra and the e-tron:



The motor in the middle is indeed for the power steering, because it is also present on the ultra.

The other, with the yellow high voltage sticker, is the electric motor/generator of the hybrid system.

I expected that there would be two such motors in the nose, one for each wheel, each delivering 75 kW. I was wrong. So the two motors are probably in the same housing on the right in your picture.

[gwyllion]

Originally Posted by manthey

ok f1 have less weight but consider that spa pole lmp1 was not so distant from the time of the last(slowest) F1 car

Qualifying in F1 last year was in wet conditions Only Q3 was sort of dry. See http://www.formula1.com/news/headlin...1/8/12451.html

The F1 pole was 1:48.298 (Vettel) and the fastest race lap 1:49.883 (Webber).

That is still a lot quicker than the LMP1 pole of McNish (2:01.579).

[henk4]

Originally Posted by gwyllion

On these two pictures you can see the difference between the ultra and the e-tron:



The motor in the middle is indeed for the power steering, because it is also present on the ultra.

The other, with the yellow high voltage sticker, is the electric motor/generator of the hybrid system.

I expected that there would be two such motors in the nose, one for each wheel, each delivering 75 kW. I was wrong. So the two motors are probably in the same housing on the right in your picture.

thanks for clarifying this, I never saw the fore part of the Ultra removed, or not covered with some cloth. (they have that hanging on the box door, so that they can immediately grab it to cover up the sensitive parts, but they sometimes forget, or think that there enough legs in the way).
It follows from Audi's statment that Ultras can be relatively easily converted into e-trons, that the location of the power steering stuff should be the same.

[gwyllion]

I believe that the picture of the ultra was taken in Spa.

Also note the small duct at the top of the e-tron nose. I doubt that this is enough to cool the hybrid motors, which are probably water or oil cooled, but it could cool some electronics box.

[henk4]

Originally Posted by gwyllion

I believe that the picture of the ultra was taken in Spa.

Also note the small duct at the top of the e-tron nose. I doubt that this is enough to cool the hybrid motors, which are probably water or oil cooled, but it could cool some electronics box.

hm, would be interesting to see the inside of the nose, how this connects with that duct.

[gwyllion]

Originally Posted by gwyllion

In the Toyota topic I already calculated some metrics (average of highest top speed, average of fastest sector 2 times, and average of fastest lap times) from the time data of the test day.

I also calculated the average lap time of the long runs (10 or more laps), like Paul Truswell did in 2011.

Morning:
Afternoon:

Contrarily to Paul's analysis, I exclude both the in and out lap. So the average is only calculated over the laps on the track.

Paul also had a look at the timing data. He concludes that Audi can do longer and faster stints than last year.

However, looking at the times from the Le Mans test day, it looks to me that the Audi R18 e-tron ultra can go further on less fuel than last year's Audi R18. What's more, it is doing faster average lap times as well. I reckon it was managing 12 laps on a tankful!

source: http://trussers.blogspot.com/2012/06...less-fuel.html

[Creep89]

So Audi is able to do more and faster laps. They are able to do 12 laps like Peugeot did last year. How did the engineers of Audi Sport do that? Less fuel, more laps.

[alexkiller8]

Originally Posted by Creep89

So Audi is able to do more and faster laps. They are able to do 12 laps like Peugeot did last year. How did the engineers of Audi Sport do that? Less fuel, more laps.

they optimized the engine, so the 2012 version can reach a power close to the one of last year but with a better fuel efficency.
If the future regulations will introduce the fuel flow meter, we all have to expect engines with ever a higher fuel efficency.

[henk4]

Originally Posted by Creep89

So Audi is able to do more and faster laps. They are able to do 12 laps like Peugeot did last year. How did the engineers of Audi Sport do that? Less fuel, more laps.

less power also....

[gwyllion]

As mentioned earlier, the 2012 rules impose a reduction in air restrictor area, and hence in power, on diesel engines of 7%. Mike calculated that Audi and Peugeot had around 610 hp in 2011. So now Audi probably has around 570 hp.

Physics says that the power to overcome aerodynamic drag increases with the cube of the velocity. Consequently, a drop in power of 7% leads to a reduction in top speed of 2.3%.

In 2011 the top speed of the R18 was around 330 km/h. If we assume that the drag of the R18 has not changed since last year, the top speed will be reduced with 7.5 km/h. That is consistent with the data from the test day: the top speed of R18 ultra is indeed around 323 km/h.

[MulsanneMike]

Originally Posted by gwyllion

As mentioned earlier, the 2012 rules impose a reduction in air restrictor area, and hence in power, on diesel engines of 7%. Mike calculated that Audi and Peugeot had around 610 hp in 2011. So now Audi probably has around 570 hp.

Physics says that the power to overcome aerodynamic drag increases with the cube of the velocity. Consequently, a drop in power of 7% leads to a reduction in top speed of 2.3%.

In 2011 the top speed of the R18 was around 330 km/h. If we assume that the drag of the R18 has not changed since last year, the top speed will be reduced with 7.5 km/h. That is consistent with the data from the test day: the top speed of R18 ultra is indeed around 323 km/h.

Yes, was thinking so too, around 7% less power. But...a wrench in the system...have it on very good authority that Audi recovered most, if not all, the power deficit.

But also remember the BHH, this was always going to change total drag. Thus the speed reduction is all attributable to the BHH in this case (as far as we're concerned). I think it means about a 3.5% increase in drag, about 30 more lbs drag at 200. This seems about right (regarding the aero effects of the BHH taking into account some mitigation) and gives me a 326 km/h top speed (I only looked the Ultra's speed, need to add the e-tron's average too--these #s will change slightly when I do that) based off last year's power figures.


Further more, I feel pretty confident in saying Toyota has less power but has compensated by creating a lower drag package. Unfortunately the proof in the pudding also is that subsequently they have less DF. So far the test data agrees with that assessment. More info in 7 days time. I'm not one thinking Toyota will be on pole.

[henk4]

Originally Posted by MulsanneMike

I'm not one thinking Toyota will be on pole.

Ha, but they got Sarrazin, if he has been sufficiently repaired.

[alexkiller8]

is hard to score the pole for toyota is audi is much faster in porsche sector! during the test toyota shown to have some km/h more in top speed, but who knows the real settings that the cars used... maybe next week we will see the audi cars to have a best top speed of toyota too. In my opinion the e-tron will run in 3.23.5, the ultra a bit slower and the toyota cars in 3.25.5 but harldy under the 3.25.0.
About the 2012 rules, i think that for audi has been more penalizing the reduction of boost pressure than the shorter air restrictors!
air restrictors reduce the power lowering the max rpm that an engine can reach, this can heavily penalize cars that use a highrev NA petrol engine but the audi engine has a revlimit under 6000rpm so if at example in 2011 the engine at 5500rpm had a torque of 770Nm now will be something like 730Nm... there is a loss of 40Nm but is always over a really great value like 700Nm!
Instead the boost pressure reduction influences the acceleration a lot and make reach the torque peak later (at least the e-tron cars can recover using the hybrid system).
About toyota poweroutput, in my opinion is all about if the engine runs over 9000rpm... if the engine will reach in someway 10000rpm or more i haven't doubt that can develope around 600hp, with a torque peak of something more 500Nm a bit under 7000rpm (just my opinions).

[Articus]

500nm? The Ferrari 458 gt2 makes more torque than that.

[alexkiller8]

the current 3.4L engines usually are projected to produce power to the highest rev possible. With this kind of displacement is useless to build a 3.4L engine mid-low revlimit if however won't develope a lot of torque.
The 458 GT is powered by a modified F142 set to reach max power in a lower revlimit than the road/gt3 version, with the aim to maximize the availabe torque. For this reason, even restricted, the engine developes around 520-540Nm with a revlimit under 6500! (the gt3 version revlimit is around 8000rpm)

[Articus]

Originally Posted by alexkiller8

the current 3.4L engines usually are projected to produce power to the highest rev possible. With this kind of displacement is useless to build a 3.4L engine mid-low revlimit if however won't develope a lot of torque.
The 458 GT is powered by a modified F142 set to reach max power in a lower revlimit than the road/gt3 version, with the aim to maximize the availabe torque. For this reason, even restricted, the engine developes around 520-540Nm with a revlimit under 6500! (the gt3 version revlimit is around 8000rpm)

Under 6500! Thats really low. Now im even more impressed at how the Ferrari's sound as godly as they do! It sounds like it revs to something alot higher than 6500.

[alexkiller8]

yes the max power is reached at 6200rpm according to various sources. Michelotto tuned the engine in a very extreme way, basicly turned the highrev stock engine in almost an american high torque/low rev engine.

[Articus]

But it doesnt sound american at all!

[henk4]

Originally Posted by Articus

But it doesnt sound american at all!

no, it makes a terrible noise, the worst sounding of all GT cars.