LMP1 diesel performance adjustment

[dj4monie]

Originally Posted by paul-collins

This is partially off topic, but on comparisons between P1 and P2, and between P2 cars:

1) Let's not forget the main reason Audi has difficulty at short twisty tracks. They have more tires to compensate for more weight, so their grip under braking is not going to be compromised. They have more torque and therefore can accelerate out of corners much better (witness McNish's starts at Houston and St Pete). They get killed in the slow corners because of their long wheelbase.

Now, how do you compensate for that?

The problem is, of course, that the diesel is a long engine and therefore the long wheelbase is part of the package - ie not at the designer's discretion.

2) on comparing the AER turbo to the NA V8 Porsche: Jon Field did show that the AER - with a restrictor break and boost increase - could compete with the Porsches. Having watched the pace of the Fernandez Lola compared to the Acura (nee Courage) chassis, I'd have to say that the Lola isn't quite up to pace with the Evo Porsche; I can't immediately compare it to last year's Porsche, though, but I don't know how much performance was increased in the Evo.

But the real limiting factor for Intersport last year is the same as it is this year in P1. Tires. Last year they were on horrid Goodyears. How Jon got as close to the Michelin shod Porsches last year is beyond me...

I'm not too sure that's totally right Paul.

The Acura-Lola has had a series of mishaps in qualifying and raceday. Its been acknowledged that the Lola currently isn't that happy over bumpy surfaces where they can run the car at min ride height. That was an admission by Fernandez himself.

He had admitted to looking forward to natural terrain tracks that are coming up on the schedule.

At times Jon Field has proven the Lola chassis is capable of keeping pace with the Porsche. There have been changes to the Porsche, but also changes to the Lola chassis as well, mostly in aero and you can say the same for the Spyder.

The Acura engine isn't in question, it thumps just as much power and torque as the Porsche V8 does.

I think not so much at Utah but at Mid Ohio is where the Audi might get shut out of the podium again.

Speaking of Intersport, Mid Ohio is a home track for that team I expect them to be closer to the pointy end by then in the Creation.

[chewymonster]

Originally Posted by JAG

No doubt a factory petrol engine will also have an advantage over off the shelf engines.

Another excellent post. This is why the performance of the Swiss Spirit Lola will be interesting.

[minimangler]

just reading down, it seems there's a few hot under the collars here...


i have to say, i'm on the petrol side here, and adjust the diesels to an actual equivalency.

[henk4]

Originally Posted by minimangler

just reading down, it seems there's a few hot under the collars here...


i have to say, i'm on the petrol side here, and adjust the diesels to an actual equivalency.

How? by letting the Peugeots run with a petrol engine and then calculate the difference in laptimes?

[SebringMG]

Originally Posted by minimangler

just reading down, it seems there's a few hot under the collars here...


i have to say, i'm on the petrol side here, and adjust the diesels to an actual equivalency.

Without a factory petrol engine you would be just levelling the diesels back to the pace of the privateer cars....then a works petrol comes along and walks over everybody and it all starts again.......

Need a factory supported engine in a works chassis before any equivalency is anything other than a stab in the dark...that is why the Swiss Spirit Lola-Audi is our best shot at working out if the current equivalency is even close to being correct.....

[Flat12-Aircool]

I predict the Swiss Spirit Audi will not finish the "Top petrol" in any of this seasons races.

Teams like Pescarolo, Zytek, Creation and engine suppliers Judd have moved forward since they last faced the R8 in 2005. I'm not saying that maybe Swiss Spirit won't perhaps out qualify the other Petrols from time to time, but over a full race a 2007 Judd V10 5.5 should be more than a match for a 2+ year old Audi design.

Do all you Swiss Spirit "Fanboys" really expect it to be 5 seconds faster than the Pescarolo's at Le Mans, or that it would've been 2 seconds faster at Monza?

[henk4]

Originally Posted by Flat12-Aircool

Do all you Swiss Spirit "Fanboys" really expect it to be 5 seconds faster than the Pescarolo's at Le Mans, or that it would've been 2 seconds faster at Monza?

the Charouz-Lola was the fastest of the petrol cars, so the chassis will be good enough. Given the Audi support to the Swiss Spirit project failures like you describe are unlikely. (I am not fanboy, I drive an HDi-FAP )

[JAG]

Originally Posted by Flat12-Aircool

I predict the Swiss Spirit Audi will not finish the "Top petrol" in any of this seasons races.

Teams like Pescarolo, Zytek, Creation and engine suppliers Judd have moved forward since they last faced the R8 in 2005. I'm not saying that maybe Swiss Spirit won't perhaps out qualify the other Petrols from time to time, but over a full race a 2007 Judd V10 5.5 should be more than a match for a 2+ year old Audi design.

Do all you Swiss Spirit "Fanboys" really expect it to be 5 seconds faster than the Pescarolo's at Le Mans, or that it would've been 2 seconds faster at Monza?

I'm not so sure, history shows turbo's are far superior to atmo engines, it's no coincidence the likes of Toyota and Audi went down this route.

From what I've read they're easier to adapt to the prevailing conditions, you can turn up the wick for ultimate power, turn it down to cruise home or in wet conditions.

As for being two seconds quicker, who knows, maybe one second.

Monza suited Peugeot down to the ground, Pescarolo were off the pace, Charouz were out early on, while the other quick runners weren't even at Monza.

[SebringMG]

I would suggest that the swiss spirit car has little chance of a win versus the diesels (just look at 2/3 of the driver line up) but it should be able able to set impressive lap times and be a good comparison as to what the best in engine technology (petrol division) can throw up!!

I think you are seriously mistaken if you beleive a judd, zytek, aer engine is even close to being the equal of the audi lump!! The judd is the closest yet but doubt it comes close on torque and certainly it would struggle on fuel economy (FSI/DI tech is not avail to anyone other than audi and mazda afaik).

[Purist]

The Audi lump has NOT seen competition development since 2002 (the original R8 program was only three years once the R8R was picked over ther R8C). Also, the engine cannot be as optimized as it was since the engine was specifically designed for the R8, and the chassis it is going into now had to have far more component flexibility built into it for use by various privateers.

Why not do a trial run with modified rules? Take the early part of the season, and rein in the diesels, and see what happens on a variety of circuits. The series all have significant breaks around June. You could probably have a MUCH MORE ACCURATE equivalency in place by Le Mans of that given year. And one thing that would help massively is to announce that this experiment is to be carried out, so that you're NOT blind-siding the competitors. It's certainly a better option than letting Audi and Peugeot run over everyone else on the whole, and then fixing things in a few years when there MIGHT be a "true" factory, petrol LMP1 that shows the imbalance in the rules. Meanwhile, the LMP1 class has been decimated, and has to be reconstituted to a significant extent (which is going to take time if Porsche only returns AFTER the rules have been changed and provide customer cars).

[gwyllion]

Originally Posted by Purist

The Audi lump has NOT seen competition development since 2002 (the original R8 program was only three years once the R8R was picked over ther R8C).

The engine electronics were further optimized to cope with restrictor changes. In 2004 for instance they switched from Bosch MS 2.8 to MS 2.9 motor management.

Originally Posted by Purist

Also, the engine cannot be as optimized as it was since the engine was specifically designed for the R8, and the chassis it is going into now had to have far more component flexibility built into it for use by various privateers.

I don't understand how an engine can be optimized for one given chassis. The engine just needs adequate cooling. Of course the motor management of the FSI engine relied on data from the Ricardo gearbox.

According conversations Sam Collins had with Wolfgang Ullrich Audi Sport is really putting serious support. E.g., during the 2 test days at Lédenon 2 Audi Sport engineers were present. So the package will work.

Originally Posted by Purist

Why not do a trial run with modified rules? Take the early part of the season, and rein in the diesels, and see what happens on a variety of circuits. The series all have significant breaks around June. You could probably have a MUCH MORE ACCURATE equivalency in place by Le Mans of that given year.

Le Mans is THE benchmark circuit and this circuit is only open once every year ACO just waits till the end of the season to make rule changes. They want rule stability during the season, in contrast to the balance of performance of IMSA (especially last year where GT1 rules were changed almost every round).

[henk4]

Originally Posted by Purist

Why not do a trial run with modified rules? Take the early part of the season, and rein in the diesels, and see what happens on a variety of circuits.

Apart from all the technical arguments, I feel that there is some underlying feeling of unacceptance and disbelief that a diesel can actually beat a petrol car. I single out the about sentence to highlight that feeling....(and no wonder it comes from the USA, the virgin territory for modern diesel designs....my comment comes from Europe, where in many countries the share of newly sold diesel powered cars already exceeds that of petrol cars)

[Hammerdown]

Just read the Henri column on DSC and Collard mentioned that the Pug was better under braking than the Pesca. Would the diesel have better engine braking compared to a petrol engine?

[henk4]

Originally Posted by Hammerdown

Just read the Henri column on DSC and Collard mentioned that the Pug was better under braking than the Pesca. Would the diesel have better engine braking compared to a petrol engine?

just to compensate for the heavier weight?
I also read the comments of Henri, and maybe Peugeot should give him some engines next year....

[Flat12-Aircool]

Originally Posted by henk4

Apart from all the technical arguments, I feel that there is some underlying feeling of unacceptance and disbelief that a diesel can actually beat a petrol car. I single out the about sentence to highlight that feeling....(and no wonder it comes from the USA, the virgin territory for modern diesel designs....my comment comes from Europe, where in many countries the share of newly sold diesel powered cars already exceeds that of petrol cars)

If there was a level playing field they probably wouldn't. They have to "max out" the capacity to a 5.5L V12 to give themselves a performance edge, with contentious things like levels of Boost pressure etc. The more nimble R8 only needed a 3.6L V8 in order to win Le Mans 5 times.

However, one of the main strengths of a Petrol engine (weight) has been cynically taken away by the ACO imposing +25kg to the LMP1 class.

[chewymonster]

Road going diesels run higher boost pressures than road going turbos. And they can easily make some major power. 204 hp form 2 liters. And 295 lb-ft of torque. The difference has shrunk dramatically.

[gwyllion]

Originally Posted by Hammerdown

Just read the Henri column on DSC and Collard mentioned that the Pug was better under braking than the Pesca. Would the diesel have better engine braking compared to a petrol engine?

When I read the article it says exactly the opossite:

the Pescarolo was “a bit quicker in medium and high-speed corners”, and also better under braking… but “Emmanuel said that the big difference was out of the corners at the beginning of each of the straights. The diesel cars really gain from 180-200 kph up to 260-270 kph, and that can only be down to engine power and torque.”

Henri observes that Peugeot has the same advantage as Audi last year at Le Mans: faster acceleration (power advantage) and same top speed, but more downforce.

He predicts they will be 5 sec slower at Le Mans.

[Adam43]

and more downforce could well explain the better braking.

[gwyllion]

Originally Posted by AdamAshmore

and more downforce could well explain the better braking.

Please read the quote about. The Pescarolo was better under braking!

The fact that the Pescarolo was quicker in medium and high-speed corners is down to better weight distribution and lower weight.

[Spyderman]

Maybe Pescarolo could organize a protest that would have all gasoline powered prototypes circulating at 90 Kph during the entire 24h Le Mans, thus fulfilling two of the ACO's main objectives: 1) Having the diesles win with no real opposition, and 2) save fuel.

That should drive home the point!

[gwyllion]

Unlikely. Henri seems to have a hard time convincing ACO.

“I think it is time all the prototype teams joined me and petitioned the ACO to do something about these iniquities in the rules. At the moment I feel like a lone voice.”

[Adam43]

Originally Posted by gwyllion

Please read the quote about. The Pescarolo was better under braking!

and more downforce should mean better under braking.

[henk4]

Originally Posted by Spyderman

Maybe Pescarolo could organize a protest that would have all gasoline powered prototypes circulating at 90 Kph during the entire 24h Le Mans

they might start making some additional white and subsequent black flags then....

[Spyderman]

Originally Posted by henk4

they might start making some additional white and subsequent black flags then....

...ACO still gets diesels winning with no opposition and will get even more savings on fuel!

[Hammerdown]

My bad! I read that completely round the wrong way. That's a reflief then!