LMP1 diesel performance adjustment

[gwyllion]

This year the Audi did quicker lap times than Pescarolo and they were even to more laps with the same amount of fuel. What should the ACO change next year to make petrol and diesel car more matched?

[SALEEN S7R]

Give the petrol engined cars a slightly larger restrictor than what they have now I would say. Okay it woudnt solve the fuel consumption issue but it would help the petrol engined cars match the diesels for pace. As for the fuel consumption issue, at the moment LMP1's have a 90 litre fuel tank, increase it to 100 litres for petrol engined cars. That should, IMO even things up between the Diesel powered cars and the petrol powered machines.

[Fogelhund]

Given that I have no clean sheet LMP1 petrol, Manufacturer built and developed car to compare against, I am having a hard time drawing conclusions.

Is it realistic to expect that a privateer developed and funded car, that is a mix of old regulations and new, to be competitive with a clean sheet design from a manufacturer?

If our goal is to even out performance differentials between teams, then why not rewards weights like Touring Cars?

[JAG]

The ACO will slightly reduce the restrictor on diesels, but to put the blame on the diesel performance is missing the point.

The R10 chassis is state of the art, the Pescarolo based on an ageing C60.

The R10 fitted with a petrol motor would have won comfortably.

What we need is factory competition, I'm quite sure a petrol engined car from a major manufactuer would have put up a much stronger fight, maybe even broke both R10s.

At the moment we have to make comparisons between a factory diesel and relatively small privateer team.

[gwyllion]

Increasing the minimum weight (diesel 950 kg and petrol 925 kg) or maybe get back to the minimum weight of 900 kg (which diesel car will not be able to reach?). More weight would reduce the advantage of the high torque (acceleration out corners), but could also increase the tyre wear.

There should definitely be difference fuel tank size. This way the marketing department can still brag about the better fuel economy but petrol cars do not get handicaped to much.

I do not know whether the restrictors need adjustment. It looks like the power of diesel and petrol look matched judging from top speed. But as MulsanneMike pointed out hybrid LMP1 are less draggy, so the Audis could have had a horse power advantage.

I think the fuel flow restrictor diameter should be kept. In this way spectators can compare the performance of the pit crew. It should take equally long to fill the whole fuel tank. So perhaps if the tank size is different, this may need adjustment as well.

[gwyllion]

Originally Posted by Fogelhund

Is it realistic to expect that a privateer developed and funded car, that is a mix of old regulations and new, to be competitive with a clean sheet design from a manufacturer?

If our goal is to even out performance differentials between teams, then why not rewards weights like Touring Cars?

It will be very interesting to want the next ALMS races. The Dyson Lolas were granted a weight reduction: 900 instead of 925 kg. I hope IMSA will throw in some extra performance adjustments (like they do in the other classes) when the Audis turn out to be too dominant; I am thinking of bigger restrictors for the Dyson cars.

[knighty]

for me the answer is quite obvious, the ACO need to downsize the restrictor and/or the boost levels of the Diesel rules........everyone knows Audi are under-quoting their power saying "650Bhp"......bull.....Peugeot are already saying 700Bhp......I dont mean to blow my own trumpet, but I design and develop diesel engines for a living and I think Peugeot are being far more honest than Audi....127 bhp / litre from a highly strung race diesel is quite do-able nowdays......a 5.0 Judd V10 only has 630Bhp......therfore the Diesel rules need aligning with the petrol rules.

but I do agree the R10 is a fine piece of kit and far superior than anything else on the grid......but in terms of engine performance, the Diesel rules are way too generous........I dont think playing around with fuel tank sizes is an option as that could be a very costly and major re-design for many of the current chassis.

[Fogelhund]

Originally Posted by gwyllion

It will be very interesting to want the next ALMS races. The Dyson Lolas were granted a weight reduction: 900 instead of 925 kg. I hope IMSA will throw in some extra performance adjustments (like they do in the other classes) when the Audis turn out to be too dominant; I am thinking of bigger restrictors for the Dyson cars.

This is a big difference, talking about series performance adjustments, over that of the basic ACO ruleset. I would agree that it is in IMSA's best interest to reward their privateers, and help them out some. I believe that the Dyson car is far from sorted though, and might take some time to do so. They were still on the Step 1 engine programming, while Chamberlain is on Step 3. Pre LM Dyson had suggested they had too many other issues to sort, to even bother with the engine upgrades.

The biggest thing that Dyson may wish to do, is to ensure that I am at all of their races. (I'm not sure if it is just me, or a combination of myself, Paul_Collins, and another poster Wildfire). The last three races that I have been at, (along with others listed), resulted in Dyson wins.

[JAG]

Let's give Dyson a few more races to sort out their car, but if by late season they are closer to the RS Spyders than the R10, we'll just have to admit the Lola chassis, maybe even Dyson, cannot compete regularly with factory teams.

It will be interesting to see how Creation/Zytek fair in the ALMS if they come over. Then we'll get a more accurate barometer on the Dyson Lolas performance. If they are signifcanty quicker than Dyson, Lola will have a lot of work to do.

[b1ackcr0w]

If Diesel makes a better race car, then why artificially balance the scales in favor of Petrol? We don't stunt Petrol Cars performance so that Steam cars can keep up?

[gwyllion]

Originally Posted by knighty

for me the answer is quite obvious, the ACO need to downsize the restrictor and/or the boost levels of the Diesel rules........everyone knows Audi are under-quoting their power saying "650Bhp"......bull.....Peugeot are already saying 700Bhp......I dont mean to blow my own trumpet, but I design and develop diesel engines for a living and I think Peugeot are being far more honest than Audi....127 bhp / litre from a highly strung race diesel is quite do-able nowdays......a 5.0 Judd V10 only has 630Bhp......therfore the Diesel rules need aligning with the petrol rules.

Of course the Peugeot 908 could be a closed car and thus get granted a bigger restrictor.

According to http://www.pescarolo.com/DP_2006.pdf the Judd GV5 S2 produces 640 hp at 8500 rpm (and 615 Nm).

So it is safe to say the diesel rules all for too much horse power.

Originally Posted by knighty

but I do agree the R10 is a fine piece of kit and far superior than anything else on the grid......but in terms of engine performance, the Diesel rules are way too generous........I dont think playing around with fuel tank sizes is an option as that could be a very costly and major re-design for many of the current chassis.

In 2005 LMP900 cars had to race with 50 kg extra, 10 liter smaller tanks and smaller restrictors.

[MulsanneMike]

Originally Posted by b1ackcr0w

If Diesel makes a better race car, then why artificially balance the scales in favor of Petrol? We don't stunt Petrol Cars performance so that Steam cars can keep up?

True...but you also have to keep in mind the ACO's paranoia about lap times below 3:30. Certainly that's academic after this year because clearly with the pace of development the cars will be below that next year. But the ACO seems to always err on the side of performance reduction when equating.

[Dani Filth]

i think a factory effort in similar fashion as Audi with a Petrol engine could've beaten Audi this year .. they had the advantaje of being "alone"

[veeten]

speaking of Judd, how about the Ricardo-Judd V-10 Diesel engine of last year. Is it still in development or has it stopped due to funding, because after the developments of this year's LeMans I'm sure that the project has found some traction.

Any news, Mike?

[pirenzo]

Originally Posted by b1ackcr0w

If Diesel makes a better race car, then why artificially balance the scales in favor of Petrol? We don't stunt Petrol Cars performance so that Steam cars can keep up?

But the diesel clearly doesn't make a better race car. It's allowed 1.5 litres more capacity than it's petrol counterparts. That's not equivalency, it's a gift...
At the end of the day, the whole diesel thing is just a ploy to get more manufacturers back in the race. All credit to the ACO for trying, but for the time being until Peugeot and others turn up, every race the R10 wins is going to be somewhat contrived IMO.

So I think just leave the diesels where they are relative to the rest. What we're really looking for is Peugeot's diesel technology vs. Audi's diesel technology, not diesel vs. petrol per se.

[marcush.]

the point is :neither Pescarolo nor Creation or Zytec or Racing for Holland ,or Courage are WORKS efforts.
This is not to say you couldn´t beat works entrys ,Joest did and others did as well .But you simply can´t can´t dream of beating Audi +Joest with outdated machinery that has not even ever had a proper 24hour test.....
and add to it a questionable driver choice AND get away with some lets hope preparation....Pescarolo had something of a proven package plus something of a driver lineup at least....
But they ran into a simple electrical problem that cost car No 2 at least second place...let alone allowed Audi to go a lot slower for a long time.
so really the privateer Teams have to point their fingers at their own nose
with regard to just why Audi had that win.Of course you need money I hear you all screaming....but this is not half of the story.Toyota has thrown a lot more into the pot then most of the teams could ever dream of and they just did not make it.But of course the first and most important thing in your plan to conquer LeMans or any other Race is to have a clear idea from where all the money should come from to make it possible....and you are standing with at least one foot in the coffin if just one of your drivers is responsible for supplying the necessary budget .....discounting of course the lmp2 and GT2 classes of course...but thats because Porsche basically left GT2 now and is not yet in LMP2 or would you disagree?
The regs are the regs leave them as they are.

[knighty]

Just had a trawl throught the 2006 diesel restrictor rules on page 24, and it states 55.9mm for 1 restrictor and 39.9 for two restrictors on a 5.5 Diesel........I'm assuming thats the size for an open top car........but where does it say the bigger restrictor size for a closed top car - I cant find it!......am sure its there......what size is it???......

[gwyllion]

On the same page (a bit down, in red) it says.

For closed cars equipped with an air conditioning system, the following restrictors diameter must be increased by :
- 0.6 mm for 1 restrictor ; ;
- 0.4 mm for 2 restrictors ;

source http://www.lemans.org/sport/sport/re..._ACO_fr_gb.pdf

[GT6]

All credit to Audi, however if they want to kill motor racing they are going about it the right way, the huge number of people that go to Le Mans and other races are there for the noise and smell of racing, for all the speed of the Audi it sounded like an electric disabled vehicle. To keep motor racing going you need to attract the public, the R8 was boring but compared to the R10 it was great sounding car.

Deisels and petrol cars should compete equally, but the teams should consider the fans, perhaps someone could send a tape of the Corvettes, Panoz or Astons to Audi. Or better still the sound of an old Audi Quatro rally car.

[Erki]

Nothing. Boring or not, it's environmentally more friendly and that should be encouraged. When other manufacturers see that diesel is better, they'll follow the same route.

[Animeishdwarf]

I think it should involve the maximum displacement of the engines, because those are way out of whack.
NA Petrol engines are limited to 6000cc
Turbo Petrol engines : 4000cc
Diesel Turbo : 5500cc
Not all equal is it?

[MulsanneMike]

Originally Posted by veeten

speaking of Judd, how about the Ricardo-Judd V-10 Diesel engine of last year. Is it still in development or has it stopped due to funding, because after the developments of this year's LeMans I'm sure that the project has found some traction.

Any news, Mike?

Nothing actually...

[Dani Filth]

Originally Posted by Animeishdwarf

I think it should involve the maximum displacement of the engines, because those are way out of whack.
NA Petrol engines are limited to 6000cc
Turbo Petrol engines : 4000cc
Diesel Turbo : 5500cc
Not all equal is it?

that's because you compare apples with prunes ..
Corvette has a 7 litre engine
Aston Martin has a 6 litre engine
Not all equal is it ??

[bernard b]

of course it's not equal, but it's supposed to get the same results
this regulation may not be perfect but is adjusted with restrictors size

the gap between a full factory team (Audi) and a full private team (Pescarolo) is not that huge. As other says, it's not only the diesel advantage

but the fact that they use less fuel on diesels appears more unfair to me
an interesting point from D Poissenot during the press conference at Le Mans is the idea of "energy equivalency" : cars should no more have the save volume of fuel (diesel or petrol), but the same amount of energy : for example 90l diesel = 100l petrol = 120l ethanol (that was already done with Nasamax team btw)

[canam]

As Audi have made such a big thing about winning with a diesel. I suggest that they use 'pump' fuel--the diesel that everyone knows and loves. It should be ugraded in a similar manner to those running petrol engines (to 101 octane) but special fuels should not be allowed.

That will kill the performance of their engine if it runs at all and show what a sham this whole exercise has been although they have dressed this one up in an 'environmentally friendly' endeavor.

BTW, does anyone know if my Audi diesel would actually run on the fuel that they use in the R10. My guess is that it wouldn't.

Ban the special fuels and that ought to generate a level playing field.