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

[Mike E]

Originally Posted by Sodemo

OK maybe I got mixed up. Can someone tell me what the engine rules are then please? Or link me to somewhere as I googled it and tried about 4 pages, lots of regulations stuff, but nothing about engines.

Is the Toyota a V6?

The Toyota is a 3.5l V6 turbo. Glickenhaus is 3.5l V8 turbo.
Engine must be a petrol-fuelled piston engine but layout and size are unlimited as far as I know.

Edit: Engine design is free except for the following restrictions:
• Only Petrol 4 stroke engines are permitted

[canaglia]

until some years ago the engine layouts allowed in IMSA were turbo 4L, turbo V6, NA V8 up to 5.5L and NA V10 up to 5.2L... don't know if rules changed in the meantime even if I am 100% sure 5.5L is still the max displacement allowed for NA.

[Adam43]

As power and power curve are regulated I guess actual configuration is less important. Of course there are reliability and packaging considerations. And cost.

[Sodemo]

Originally Posted by Mike E

The Toyota is a 3.5l V6 turbo. Glickenhaus is 3.5l V8 turbo.
Engine must be a petrol-fuelled piston engine but layout and size are unlimited as far as I know.

Edit: Engine design is free except for the following restrictions:
• Only Petrol 4 stroke engines are permitted

Ah ok, my bad. I read some time ago the rules and I must have read it wrong, I mistook "mandatory 4-stroke" for "mandatory 4-cylinder".

[Sodemo]

Sorry to double post in quick succession, is there any development allowed or is that largely pointless if everything is going to be BOP'ed?

[Mike E]

Unless I am mistaken, which is very possible, LMH and LMDh cars will be homologated for 5 years. I guess this is the whole package, including powertrain. So in that respect, continued development will not be permitted.
And while engine layout is free, max power is limited to 670bhp and torque curves etc will be managed through BoP.

[Sodemo]

Originally Posted by Mike E

Unless I am mistaken, which is very possible, LMH and LMDh cars will be homologated for 5 years. I guess this is the whole package, including powertrain. So in that respect, continued development will not be permitted.
And while engine layout is free, max power is limited to 670bhp and torque curves etc will be managed through BoP.

Hmm, so then it becomes a matter of which team the ACO wants to win on that particular weekend.

I think allowing teams to develop a small aspect of the car which wouldn't be a large performance factor would be the way I would approach it. This way teams could potentially pour money into developing one minor aspect, but it wouldn't be a thing which teams could gain a large amount of performance no matter how much they developed it. The obvious thing would be the hybrid system, or an aspect of it. Maybe suggest that they fit a OEM spec road going electric motor of a certain size (modified), but it can have unlimited power output.

[TF110]

Hopefully it's not a bop lottery each race but we'll see soon.

[helgi]

I bet it's going to be a pretty predictable stuff. You'll need some accuracy with calculations - and voila - the finishing order even before race starts (of course some incidents are not predictable).

[Sodemo]

I guess if the power output is capped the teams are just going to go for whatever is the most fuel efficient engine design, since there is no point in going for an engine design with loads of power as it will just be capped. I suppose that means nothing naturally aspirated and would have to be turbo charged. With that in mind are most going to go for a V6 turbo? Would anyone go with a straight six or a straight five? I guess a V6 has weight distribution advantages and maybe a V4 is more likely? Was the previous Porsche LMP1 a V4?

[Mike E]

The only engines announced so far for LMH and LMDh are V6 and V8 turbos. Alpine will be running a naturally aspirated Gibson V8 in their grandfathered LMP1.

[Aysedasi]

Originally Posted by helgi

I bet it's going to be a pretty predictable stuff. You'll need some accuracy with calculations - and voila - the finishing order even before race starts (of course some incidents are not predictable).

Well, let's just hope not, shall we?

[canaglia]

Originally Posted by Sodemo

I guess if the power output is capped the teams are just going to go for whatever is the most fuel efficient engine design, since there is no point in going for an engine design with loads of power as it will just be capped. I suppose that means nothing naturally aspirated and would have to be turbo charged. With that in mind are most going to go for a V6 turbo? Would anyone go with a straight six or a straight five? I guess a V6 has weight distribution advantages and maybe a V4 is more likely? Was the previous Porsche LMP1 a V4?

in theory it should work like this, but since lmh and lmdh will be bop classes, lack of fuel efficiency will be compensanted by larger fuel tank and fuel rig.
I don't think we are going to see another V4 soon

[Lasse]

Originally Posted by canaglia

in theory it should work like this, but since lmh and lmdh will be bop classes, lack of fuel efficiency will be compensanted by larger fuel tank and fuel rig.
I don't think we are going to see another V4 soon

But having a fuel efficient car would be preferable? A lighter car would in theory mean less tyre wear and be more nimble?

The question is if anyone is willing to go that far in a BOP class?

[Mike E]

The regulations specify minimum weight limits for both car (1030kg) and engine (165kg).

[canaglia]

Originally Posted by Lasse

But having a fuel efficient car would be preferable? A lighter car would in theory mean less tyre wear and be more nimble?

The question is if anyone is willing to go that far in a BOP class?

petrol is not that heavy, 20lt of extra petrol inside a larger fuel tank is 15kg, just to give an example. To design, develope and produce a high efficient ICE is required an insane amount of know how, time and most of all money... with the risk to throw away everything done like first 2 versions of 919 engine.

[Sodemo]

Originally Posted by Mike E

The regulations specify minimum weight limits for both car (1030kg) and engine (165kg).

I guess the question is though, how light can the teams make the cars and then just ballast up the car to min weight regulations?

[canaglia]

Originally Posted by Sodemo

I guess the question is though, how light can the teams make the cars and then just ballast up the car to min weight regulations?

As long the car isn't lighter than 1040kg during technical scrutineering guess nobody would care about how heavy the car is unballasted
oreca 07 because of bop must to be ballasted up to 930kg but it could realistically run lighter than 800kg.
With LMH long about 5m and powered by bigger/heavier ICE, I think that ballast will be critical to get the best possible F/R weight distribution.
More than 10 years ago, peugeot 908HDi due the massive V12 twinturbo, barely could stay in the reg. min. weight of 930kg, infact many times ran overweighted and due the impossibility to add extra ballast, it had almost the 60% of weight on rear.

[Lasse]

But the minimum weights are for the car only right? So if a car is fuel efficent it will be lighter in racetrim (with fuel) than other cars having bigger fuel tanks (which also weigh more, meaning less ballast weight for the optimal weight distribution).

F1 cars are said to be running less fuel than they are allowed, as the weight savings make up more time than the loss of lift and coast. This is for a 1½ hour race. Surely there must be advantages like this when running for 6-24 hours? And yeah, F1 is a totally different race series and they are lighter, but still. Otherwise why are all the drivers skinny if a few extra kgs dont hurt?

As I see it, in a BOP class it is about finding the small "loopholes", the question is how far you wanna take it as in the end you'll properly be BOP'ed back. Or what am I missing?

[Akrapovic]

Originally Posted by Lasse

But the minimum weights are for the car only right? So if a car is fuel efficent it will be lighter in racetrim (with fuel) than other cars having bigger fuel tanks (which also weigh more, meaning less ballast weight for the optimal weight distribution).

F1 cars are said to be running less fuel than they are allowed, as the weight savings make up more time than the loss of lift and coast. This is for a 1½ hour race. Surely there must be advantages like this when running for 6-24 hours? And yeah, F1 is a totally different race series and they are lighter, but still. Otherwise why are all the drivers skinny if a few extra kgs dont hurt?

As I see it, in a BOP class it is about finding the small "loopholes", the question is how far you wanna take it as in the end you'll properly be BOP'ed back. Or what am I missing?

Yes there are advantages in doing this in an endurance race, but they are often cancelled out by other things.

Brimming the car gets you longer on a tank of fuel. An extra lap or so per stint will gain you a lot in pit stop sequences. You'll also get extra flexibility regarding pit stops rather than being forced into a set strategy. You'll also save far more under a yellow than you could from lift and coast. So the gains are less obviously.

[chernaudi]

Not to mention that under the LMH/LMDH rules, there's no more lift and coast. Fuel flow meters are now being used as a BOP tool like air restrictors used to be.

Also for weight distribution, most LMP cars prior to the Acura ARX-02 did have weight distribution similar to F1 cars, Indy cars and most mid engine road cars (or the 2017-present Porsche 911 RSR). It was only when running the wider front wheels and tires became appealing that teams pushed for closer to 50/50 weight distribution. Up until that point, it wasn't uncommon for front wheels/tires to be 1-1.5 inches narrower than the rears for WD reasons (though Audi on the R10 ran taller tires to put more weight up front), and even current DPI/LMP2 cars are set up that way.

[Mike E]

GreenGT to provide powertrain (battery, motor, transmission) for new hydrogen class. Fuel cell stack open to development.

http://www.dailysportscar.com/2021/0...ogen-cars.html

[S griffin]

Let's see how well the hydrogen class works, it needs to be worth it. Bit limited on innovation, apart from the fuel cell

[canaglia]

Originally Posted by Lasse

But the minimum weights are for the car only right? So if a car is fuel efficent it will be lighter in racetrim (with fuel) than other cars having bigger fuel tanks (which also weigh more, meaning less ballast weight for the optimal weight distribution).

F1 cars are said to be running less fuel than they are allowed, as the weight savings make up more time than the loss of lift and coast. This is for a 1½ hour race. Surely there must be advantages like this when running for 6-24 hours? And yeah, F1 is a totally different race series and they are lighter, but still. Otherwise why are all the drivers skinny if a few extra kgs dont hurt?

As I see it, in a BOP class it is about finding the small "loopholes", the question is how far you wanna take it as in the end you'll properly be BOP'ed back. Or what am I missing?

the min. weight is the dry weight of the car with no fuel and no driver inside. In ACO/IMSA teams can't use special petrol mixture, so 1lt of petrol is likely about 0.75kg as the one you can find in road gas stations. Difference of weight is not that big between cars with different fuel tanks size, or to be more accurate, it's not this small weight difference that justifies a better/worse performance in a long endurance race.
About drivers weight "bop", on each car is mounted a min. ballast to let each driver "virtually" weight not less than 80kg... explain better... at example, in toyota #7 kobayashi is 68kg, conway 72kg, lopez 75kg. Will be installed a 12kg ballast to have in each situation a min.80kg driver inside.
That's basically one of reasons why porsche used to have big boys in the same car.

F1 is a different matter, cars can load up to 110KG in fuel tank for the race, according to each track forecasted consumes, sometimes are required all of them in start/stop tracks like abu dhabi, in other tracks like monza are required less because cars are in low downforce configuration.
But despite anything, 110KG are not enough to cover the >300km GP distance, so drivers have to lift and coast and use different engine maps to get to the end the race with still some fuel. It's just formula saving.

[canaglia]

Originally Posted by chernaudi

Not to mention that under the LMH/LMDH rules, there's no more lift and coast. Fuel flow meters are now being used as a BOP tool like air restrictors used to be.

Also for weight distribution, most LMP cars prior to the Acura ARX-02 did have weight distribution similar to F1 cars, Indy cars and most mid engine road cars (or the 2017-present Porsche 911 RSR). It was only when running the wider front wheels and tires became appealing that teams pushed for closer to 50/50 weight distribution. Up until that point, it wasn't uncommon for front wheels/tires to be 1-1.5 inches narrower than the rears for WD reasons (though Audi on the R10 ran taller tires to put more weight up front), and even current DPI/LMP2 cars are set up that way.

If I have to be totally honest the 50/50 of 2009 ARX-02 is more a PR myth to me, like 2014 R18 etron which audi claimed the same.