[WEC] LMP Future Regulations (was Le Mans EVO rules - now hypercar rules)

[gwyllion]

Originally Posted by gwyllion

Cost capped LMP2s also get a slightly bigger fuel flow restrictor than non-cost capped LMP2s. I don't understand the reasoning behind this...

http://www.lemans.org/en/races/24h/u...ours_3755.html gives an explanation.

“What about the LM P2s (Le Mans Protoptype 2): Oreca–Nissan, Honda Performance Development, OAK-Pescarolo etc).?”
VB: “As the ACO gave an undertaking that all cars not meeting the capped price ceiling should not be quicker than those complying with the 2011 regs (max. price: 345 000 euros), an adjustment has been made to the refuelling nozzle (+ 3.5 mm for the 2011 cars). Concerning the engines we’ve seen that the Juud seems slightly down on performance, so we’ve adjusted its power as we did for the Honda Performance Development engine.”

So this rule is meant to screw the HPD powered cars even more. Not only will they lose time on the track because of their power disadvantage, they will lose extra time in the pits because of slower refueling.

The bottomline seems to be "comply with the cost cap or go away"

[JAG]

Originally Posted by Pandamasque

So if P1s go 3 seconds faster, they'll be only 6 seconds off the pace?

All things being equal a 2011 P1 should be quicker than a 2010 P2, the latest changes will give them additional pace, and gain more time in the pits.

At Sebring there was an acceptance diesels were holding a little back, but Highcroft kept them honest and you could see the performance of both technologies was in the same ball park, I don't think 3.36 at the Le Mans test day is representative.

Factory teams wouldn't pour so many resources into a program if they didn't think it would give them a performance advantage, it's why Audi were dominant with the petrol R8. As a note, Audi's R8R qualified in 3.34.891 on it's Le Mans debut, the quickest R8C did 3.42.155, pole was 3.29.930 by the GT-ONE.

http://www.racingsportscars.com/phot...999-06-13.html

[gwyllion]

Originally Posted by Dead-Eye

"was" being the operative word here

The rules don't state that production engine on which a LMP2 engine is based, should still be on sale.

a. The engine must be made in a minimum of 1000 units in 12 consecutive months and come :
− Either from a grand touring car,
− Or from a large production car.
It is made reliable for competition use and developed to reach the output target of 450 hp without exceeding the price below:

That is the only requirement and a long list of the modifications that are allowed.

[gwyllion]

Originally Posted by gwyllion

Mike's source says 10% more power is worth 2.6 sec in Le Mans. So that restrictor cut (2-3%) is worth almost nothing.

Okay, I focussed too much on the minor restrictor increase, which is good for only 1 sec a lap. It seems that the biggest performance balance change is the difference in fuel flow restrictor:

Let’s start with the modifications to the refuelling nozzle, particularly the slide, which can be adjusted in a consistent fashion. Changing a simple component in the hose can increase the difference in refuelling times by over twenty-two seconds, the equivalent of two seconds a lap over the Le Mans 24-Hours race. It’s a simple and inexpensive measure for the teams.

So petrol cars get an improvement in average lap time of in total 3 seconds.

Some people questioned the weight reduction of the grandfathered Oreca 908 (-15 kg). The reduce fuel restrictor also applies for their car. So petrol cars also gain 2 second a lap on the Oreca 908.

[Deleted]

Originally Posted by gwyllion

The famous technical bulletin #18 is availabe on the ACO website: http://www.lemans.org/wpphpFichiers/...djustments.pdf

It gives a clear table with the BoP of the GTE class. The Ferraris are the only cars without a restrictor/weight/gurney/tank size break.

That's one nice air restrictor on the Jag. And still nowhere.

Huge break for the Jetalliance Evoras, but I wouldn't expect any miracles from those cars at this early stage of development.

[gwyllion]

The Aston Martin Vantage is the king of performance adjustments
They get a break in every column in the table: -50 kg weight, +1.4 mm restrictor, -10 mm gurney flap and +5 liter fuel tank.

Also note that a distinction is made between BMW M3 Europe and BMW M3 USA. What is that about?

[chernaudi]

The M3 ALMS cars are probably still built to ALMS GT2S specs (the class that was originally intended for sports sedans, but now applies to GT3 cars and other vehicles that don't fully fit in with the ACO's regs).

The GT2S M3s had a transaxle gearbox (now also allowed on the ACO cars since it's now an option on the production M3?) and ditched the MacPherson strut IFS on the production M3 in favor of double wishbone/multi-link IFS. The ACO cars originally had the strut suspension, and, at least at first, normal gearbox.

I'm not sure what this has to do with the LMP regs, aside from the BOP discussion, which they're have been some whopping bombs dropped across the board.

[AGD]

I believe the European and American BMWs are the same now. They are probably referring to last year's American M3. They also have the Spyker on there even though it has not run at all this season.

[gwyllion]

Originally Posted by gwyllion

Okay, I focussed too much on the minor restrictor increase, which is good for only 1 sec a lap. It seems that the biggest performance balance change is the difference in fuel flow restrictor.

A quick and dirty calculation to determine the impact of the performance balance changes.

In Spa the winning Peugeot did 161 laps in 6 hours, while the best petrol (Pescarolo) only did 156 laps. That means an average race lap time of 2:14.9 and 2:19.4 respectively. This puts the petrols within 3.3% of the diesels.

During the race the best diesel and best petrol did 6 pitstops. According to the ACO petrol cars will gain 22 sec every pitstop. That means 132 sec or around 1 lap over the whole race. Lets assume that the best diesel only did 160 laps. That means an average race lap time of 2:15.8 for the best diesel. This puts the petrols within 2.6% of the diesels.

The expert source of Mike says that 10% more power is worth around 2.6 sec at Le Mans. So a restrictor break of 3% is probably worth around 0.8 sec at Le Mans. Lets assume that means around 0.5 sec in Spa or 80 sec over the whole race. That means an average race lap of 2:18.9 for the best petrol. This puts the petrols with 2.3% of the diesels.

That is still outside the 2% rule

[MulsanneMike]

Originally Posted by gwyllion

A quick and dirty calculation to determine the impact of the performance balance changes.

In Spa the winning Peugeot did 161 laps in 6 hours, while the best petrol (Pescarolo) only did 156 laps. That means an average race lap time of 2:14.9 and 2:19.4 respectively. This puts the petrols within 3.3% of the diesels.

During the race the best diesel and best petrol did 6 pitstops. According to the ACO petrol cars will gain 22 sec every pitstop. That means 132 sec or around 1 lap over the whole race. Lets assume that the best diesel only did 160 laps. That means an average race lap time of 2:15.8 for the best diesel. This puts the petrols within 2.6% of the diesels.

The expert source of Mike says that 10% more power is worth around 2.6 sec at Le Mans. So a restrictor break of 3% is probably worth around 0.8 sec at Le Mans. Lets assume that means around 0.5 sec in Spa or 80 sec over the whole race. That means an average race lap of 2:18.9 for the best petrol. This puts the petrols with 2.3% of the diesels.

That is still outside the 2% rule

Ah, but just barely outside the 2% rule. The ACO will pat themselves on the back and say, "Well done!"

[gwyllion]

In case people were wondering, the whole balance of performance methodology is explained in the sporting regulations (released on 17/12/2010). I highlight some sentences of the rule:

1.3 – Balance of Performance of the different technologies of LM P1 Propulsion

In order to maintain the gap between the different power train technologies within a range of 2% of lap times, the ACO will keep the possibility to adapt the performance of the slowest technologies of cars under the following condition: The reference will be the calculation of average of lap times of the fastest car of each technology. The average of lap times will be calculated on a number of laps corresponding to 50% of the distance of the races (average of the best laps).
The models of cars from slowest technologies must have participated in at least at 2 races minimum and must have been regularly classified to benefit from the application of the rule.
A 2% gap average should be observed on these 2 races.

The ACO will keep the possibility to modify the application of this rule if the result of the adjustment does not permit reaching the target.

The first adjustment will be applied if necessary at the 3rd event of the 2011 season under this regulation. A maximum of 2 adjustments can be applied in the season for a technology.

The ACO will ask, if necessary, any information to the manufacturer / team in order to be assisted in his analysis. Any information will be kept strictly confidential. Any competitor who deliberately gives false information, or try to influence an adjustment process by hiding his real level of performance will have his ACO homologation form withdrawn.

The petrol cars are the slowest technology, so their performance has been adapted.

Aston Martin, Highcroft, and Hope Racing have no participated in 2 races, so they don't benefit from performance adjustments.

[MitchZ06]

Originally Posted by MulsanneMike

Ah, but just barely outside the 2% rule. The ACO will pat themselves on the back and say, "Well done!"

Dont you mean bien joué?

[gwyllion]

My quick calculation was done based on the average lap time over the whole race distance (161 laps). The ACO calculates the average lap times over half the race distance, so the 80 best laps. That could make a small difference.

[gwyllion]

In http://86400.fr/articles/159-equival...11-suite-a-fin Laurent makes some good points. Will the privateers be able to complete the driver change in time with the super fast refuelling? How much will the bigger restrictor influence the fuel economy?

According to Duncan Dayton (see here) the fuel fill time used to be around 32 sec for petrol cars and around 25-27 sec for Audi and Peugeot.

With the new rule, petrol cars will have a 22 sec advantage. It is unclear whether that advantage is absolute or relative to the previous situation (so 15-17 sec). In the former case, we are talking about fuel fill times of around 10 sec (!) for petrol and 32 sec for diesel. In the later, a fuel fill time of around 16 sec for petrol and 32 sec for diesel.

[littleman]

Petrol cars are not the slowest technology, but as long as Audi and Peugeot want to showcase diesel engines then they're going to be made to look that way.

Petrol engines have improved dramatically over the past decade but no major manufacturer has bothered to produce one for Le Mans until these stupid regs give them a chance.

I've heard rumours that Peugeot are going to switch to petrol engines in the near future - I bet the ACO make damn sure the petrol rules work then!

[littleman]

PS: I think HPD are waiting for Peugeot to switch to petrol power before they get really serious with their own LMP1 project......................

[gwyllion]

Originally Posted by littleman

Petrol engines have improved dramatically over the past decade but no major manufacturer has bothered to produce one for Le Mans until these stupid regs give them a chance.

Which dramatic improvements are you referring to? The last big improvement in petrol race engines was direct fuel injection which Audi debutted in 2001.

[alexkiller8]

Originally Posted by littleman

PS: I think HPD are waiting for Peugeot to switch to petrol power before they get really serious with their own LMP1 project......................

then will be a very long wait...

[littleman]

With the use of modern electronics and lightweight materials, petrol engines are now both more powerful and fuel efficient than ever before.

A 2.4 litre V8 F1 engine can now produce circa 750bhp, with KERS can top 800bhp, can rev to 19,000rpm and above all, are proving to be very reliable.

If you were to scale this up to a 3.4 litre petrol engine,tuned to race for 24hrs, then I've no reason to believe the performance figures would be any different.Probably less revs but still the same bhp figures with more torque.

Providing the regs don't favour diesels, which they won't when Peugeot switch, then a petrol engine is easily capable of winning Le Mans.

[Victor_RO]

Those engines still don't last more than 2000 km between rebuilds. An engine that wins Le Mans and breaks the distance record does probably about 6500-7000 km during Le Mans week (5500 in the race plus warm-up and at least one quali session).

[littleman]

As you say, a modern 2.4 litre F1 petrol engine will run 2,000km before a rebuild is required.By definition then, we already know for starters that a 1000km race wouldn't pose them any reliability issues.

The current F1 engines are producing circa 312bhp per litre so a modern 3.4 litre version would produce circa 1000bhp.

A detuned engine, specifically built for Sports Car racing, could produce 750 to 800bhp with its eyes shut!

[gwyllion]

Originally Posted by littleman

If you were to scale this up to a 3.4 litre petrol engine,tuned to race for 24hrs, then I've no reason to believe the performance figures would be any different.Probably less revs but still the same bhp figures with more torque.

A lot less revs with the air restrictors. F1 engines only have a rev restriction.

I fail to see how "modern electronics and lightweight materials" will bring big improvements to the existing LMP1 NA petrol engines that are supplied by HPD, Judd, Toyota and Zytek.

As I said earlier, the biggest "recent" improvement in race petrol engines is direct injection. It gave the Porsche MR6 engine a small increase in power and torque and reduction in fuel consumption.

If a manufacturer wants to win Le Mans with a petrol engine, they will most likely do it with a turbocharged engine + KERS.

[gwyllion]

Originally Posted by littleman

As you say, a modern 2.4 litre F1 petrol engine will run 2,000km before a rebuild is required.By definition then, we already know for starters that a 1000km race wouldn't pose them any reliability issues.

Victor_RO just explained that the engine has to last around 7000 km

Originally Posted by littleman

The current F1 engines are producing circa 312bhp per litre so a modern 3.4 litre version would produce circa 1000bhp.

A detuned engine, specifically built for Sports Car racing, could produce 750 to 800bhp with its eyes shut!

Please search the archives on the forum.

In the past a number of persons have stated that unrestricted petrol engines will produce a certain power output that is higher than what the restricted diesel engines produce now. These persons always conveniently forget that the diesel engines will also produce a lot more power without restrictors/boost pressure limitations...

Moreover, your hypothetical engine which produces 33% more power than the current petrol engines (800 vs 600 bhp), will also consume 33% more fuel. That means only 8 laps instead of 12 laps on a full fuel tank in Le Mans.

BTW I think you shoud talk to hcl123. He considered petrol engine completely obsolete in comparison to diesel engines

[arakis]

Originally Posted by gwyllion

Victor_RO just explained that the engine has to last around 7000 km
Please search the archives on the forum.

In the past a number of persons have stated that unrestricted petrol engines will produce a certain power output that is higher than what the restricted diesel engines produce now. These persons always conveniently forget that the diesel engines will also produce a lot more power without restrictors/boost pressure limitations...

Moreover, your hypothetical engine which produces 33% more power than the current petrol engines (800 vs 600 bhp), will also consume 33% more fuel. That means only 8 laps instead of 12 laps on a full fuel tank in Le Mans.

BTW I think you shoud talk to hcl123. He considered petrol engine completely obsolete in comparison to diesel engines

A turbocharged 3.5L petrol engine would blow any turbocharged 3.5L diesel out of the water with bouth hp and torque figures, provided they have the same restrictors!!!

People seem to forget that you are comparing turbo Diesel with NA petrol, how about same capacity same charging same restrictors, I would love to see a manufacturer that would run a diesel then

[SimonXS]

Originally Posted by arakis

A turbocharged 3.5L petrol engine would blow any turbocharged 3.5L diesel out of the water with bouth hp and torque figures, provided they have the same restrictors!!!

People seem to forget that you are comparing turbo Diesel with NA petrol, how about same capacity same charging same restrictors, I would love to see a manufacturer that would run a diesel then

My point exactly.

I find it massively unfair that Diesels are dominating with Forced Induction, yet there are no options to build a decent version in petrol. 2.0ltrs is not enough as Aston Martin are finding out right now, struggling to produce 400bhp.

I think 2.5 would be ideal for petrol, would be ideal for a V6. Nissan with their current knowledge with the 350Z/Skyline would be ideal to develop such and engine.