[WEC] BoP. Brilliant or Pants.

[S griffin]

Originally Posted by Matador

What say you? One exhibition race at the end of the year, minimum weight, maximum power no points but a special trophy?





They managed okay at 1080kg last year, but I think that it would certainly be unfair with how far along the development curve Porsche and Ferrari have come. They'd have all right to be salty about it.

Yes I think an exhibition race would be a great idea, although the problem is it might expose the failings of BoP and the series organisers wouldn’t want that

[Adam43]

Ooo ooo ooo. I’ve got it.

We could have one where all the GT cars are the road car equivalents.

Ooo, and one where they swap drivers between teams. So we know it’s not the driver.

And one where we don’t have to have bronze drivers - get the best in there and only people without money.

And with no tyre restrictions.

And one with no engine and battery power and energy restrictions. Or any weight limit.

No SC or FCY rules, obviously.

And better liveries. They could all be blue and orange.

It could be at Silverstone! Except let’s get the gravel traps back. Scrub that make it Brands.

Nailed it! Thank you.

[Matador]

Originally Posted by Adam43

Ooo ooo ooo. I’ve got it.

We could have one where all the GT cars are the road car equivalents.

Ooo, and one where they swap drivers between teams. So we know it’s not the driver.

And one where we don’t have to have bronze drivers - get the best in there and only people without money.

And with no tyre restrictions.

And one with no engine and battery power and energy restrictions. Or any weight limit.

No SC or FCY rules, obviously.

And better liveries. They could all be blue and orange.

It could be at Silverstone! Except let’s get the gravel traps back. Scrub that make it Brands.

Nailed it! Thank you.

Add purple liveries and you've got it. **clinks glass**

[Adam43]

Good compromise.

[Articus]

Originally Posted by S griffin

Yes I think an exhibition race would be a great idea, although the problem is it might expose the failings of BoP and the series organisers wouldn’t want that

How would an exhibition race expose the failings of BOP?


A Lexus RCF and a BMW M4 would never hold a candle to a Ferrari 296 on a racetrack, but BOP makes it possible. The purpose of the BOP is to balance cars that are designed to different performance targets. Faster cars will be slowed. This is not a failing. It is a feature.

[Gerard C]

Originally Posted by Articus

This is not a failing. It is a feature.

+ 1

[Articus]

I have decided to discuss the origins of the straight line speed advantage of the Ferrari. I think the explanation is simple. The greenhouse (cockpit dome) of the Ferrari is much smaller than that of rivals. There is simply less frontal area to push through the air and that is why it is so slippery even with a big powercut above 250km/h. See for yourself:

Porsche vs Ferrari (Ferrari smaller):


Toyota vs Ferrari (Ferrari smaller):


Alpine vs Porsche (Alpine smaller):


Porsche vs Lamborghini (Lamborghini much smaller):


Lamborghini and Alpine were two of the fastest LMDh cars on the straights at Le Mans. Porsche the 2nd slowest. It doesn't surprise me. Additionally, I think the Lamborghini is going to make waves next year at Le Mans.

Something to remember is that each of the LMDh manufacturers was trapped by the LMP2 origins of their tubs. The Multimatic LMP2 car was never anything good.

[chernaudi]

Only problem with that is that the Downforce to Drag ratio for all cars is set in both the BOP and technical regs as being 4:1, in an attempt to limit aero development and minimize aero discrepancy between the cars. So the cars overall should produce similar downforce and drag levels.


Also, the current Multimatic LMDH/GTP tub is in no way related to the monstrosity that Multimatic got stuck with that Riley designed back in 2017.

[Adam43]

They aren’t all exactly the same downforce to drag ratio. They are all within a lift and drag window. They do produce similar downforce and similar drag levels, but not the same.

So there is no problem with that. There isn’t anything to say that they should all have the same drag, the same downforce, or the same top speed. They are just similar performance. Which they are. More than they even have been.

Articus. Thanks for that comparison

[Articus]

Maybe I shouldn't overstate it. Greenhouse size is not the "only" reason. I just think it could be a contributing factor. It cannot be a coincidence that the Ferrari greenhouse is so small, and they are so fast on the straights but maybe I'm using too much confirmation bias...

[Adam43]

I’m sure it helps and ultimately contributes to how they got to their lift / drag. Like the rest they were within the same lift and drag, so if that is less draggy (it also helps produce more rear wing downforce) then it will compensated somewhere else as chernaudi suggests.

[Articus]

Originally Posted by chernaudi

Only problem with that is that the Downforce to Drag ratio for all cars is set in both the BOP and technical regs as being 4:1

Is there a reference for this 4:1 factor? I have never seen it anywhere. My understanding is that the cars must fit inside of a window:



There may be an upper limit to efficiency (the lower line in the picture above), but that doesn't mean all of the cars are sitting on the bottom line at the maximum aero efficiency. They can also be "less efficient". Every car having a 4:1 lift to drag ratio is a physical impossibility and I say that from a technical point of view. The lift and drag change when the ride height changes or when the brake duct blanking changes (permitted), and it does not occur in a linear way. A constant 4:1 ratio is not possible.

This point is implied by the following line of the lmh/lmdh technical regulations:



I could be mistaken but the fact that the rear wing angle can be changed already proves that the cars don't all run at a 4:1 lift to drag ratio at all times. If this number is legitamate, it is likely just an "upper limit" to the efficiency to prevent the expense associated with chasing more aerodynamic efficiency in the windtunnel.

[Matador]

Originally Posted by Articus

I have decided to discuss the origins of the straight line speed advantage of the Ferrari. I think the explanation is simple. The greenhouse (cockpit dome) of the Ferrari is much smaller than that of rivals. There is simply less frontal area to push through the air and that is why it is so slippery even with a big powercut above 250km/h. See for yourself:

Porsche vs Ferrari (Ferrari smaller):


Toyota vs Ferrari (Ferrari smaller):


Alpine vs Porsche (Alpine smaller):


Porsche vs Lamborghini (Lamborghini much smaller):


Lamborghini and Alpine were two of the fastest LMDh cars on the straights at Le Mans. Porsche the 2nd slowest. It doesn't surprise me. Additionally, I think the Lamborghini is going to make waves next year at Le Mans.

Something to remember is that each of the LMDh manufacturers was trapped by the LMP2 origins of their tubs. The Multimatic LMP2 car was never anything good.

Exactly what I've been alluding to in some other thread regarding the greenhouse of the GR010 (check how narrow the greenhouse is on their H2 Concept)

[Articus]

Originally Posted by Matador

Exactly what I've been alluding to in some other thread regarding the greenhouse of the GR010 (check how narrow the greenhouse is on their H2 Concept)

I might be making this up, but is it possible that while the regulations were evolving in late 2019/2020 that at some point Toyota intended to produce a 2 seater GR010 for the road, and then the regulations changed and there was no requirement to build the road car?

This would be an explanation for why Toyota ended up with a larger greenhouse than Ferrari. They were caught out by the regulations changes.

The Aston Martin is another car that I'm curious about. That car was a 2 seater production car from the outset and there might be a drag penalty from it. The Ferrari was never designed as a 2 seater. It's only objective was to win Le Mans. Ferrari did what Ford did for 2016. They built a race car perfect for Le Mans and then retrofitted it with road car parts and sold a road car in order to make it fit into the GTE category. Not quite a homologation special, but close to it.

[Articus]

Originally Posted by Matador

Exactly what I've been alluding to in some other thread regarding the greenhouse of the GR010 (check how narrow the greenhouse is on their H2 Concept)

Yes I have seen it now. It is a pure single-seater cockpit, very narrow.

[Adam43]

Originally Posted by Articus

I could be mistaken but the fact that the rear wing angle can be changed already proves that the cars don't all run at a 4:1 lift to drag ratio at all times. If this number is legitamate, it is likely just an "upper limit" to the efficiency to prevent the expense associated with chasing more aerodynamic efficiency in the windtunnel.

And here is the engineering brilliance of the regulations and where the teams need engineering brilliance to win on a race weekend.

It is all very well being within the window, but how do you maintain a high level of performance through all attitudes, set-ups and and conditions.

[joeb]

Originally Posted by Articus

I have decided to discuss the origins of the straight line speed advantage of the Ferrari. I think the explanation is simple. The greenhouse (cockpit dome) of the Ferrari is much smaller than that of rivals. There is simply less frontal area to push through the air and that is why it is so slippery even with a big powercut above 250km/h. See for yourself:

Porsche vs Ferrari (Ferrari smaller):


Toyota vs Ferrari (Ferrari smaller):


Alpine vs Porsche (Alpine smaller):


Porsche vs Lamborghini (Lamborghini much smaller):


Lamborghini and Alpine were two of the fastest LMDh cars on the straights at Le Mans. Porsche the 2nd slowest. It doesn't surprise me. Additionally, I think the Lamborghini is going to make waves next year at Le Mans.

Something to remember is that each of the LMDh manufacturers was trapped by the LMP2 origins of their tubs. The Multimatic LMP2 car was never anything good.

Nice comparison, I wonder how it looks with the Caddy and BMW? ie. the other Dallara cars.

[tomcug]

Originally Posted by Articus

I have decided to discuss the origins of the straight line speed advantage of the Ferrari. I think the explanation is simple. The greenhouse (cockpit dome) of the Ferrari is much smaller than that of rivals. There is simply less frontal area to push through the air and that is why it is so slippery even with a big powercut above 250km/h. See for yourself:

Good analysis, thx. It surely makes sense even if this isn't the only factor influencing the straight line speed (sure isn't). Still, BOP must balance this better next year, for example Toyota getting the power boost past 250 kph and Porsche not wasn't fair.

Originally Posted by Articus

Something to remember is that each of the LMDh manufacturers was trapped by the LMP2 origins of their tubs. The Multimatic LMP2 car was never anything good.

All are brand new designs:
https://www.multimatic.com/press/mul...e-porsche-963/

[Adam43]

It’s not that simple and BoP isn’t about matching the top speeds.

If you did that then you need to match the performance of the Porsche, say, in the twiddly bits where it had an advantage.

There isn’t anything to say that they should all have the same drag, the same downforce, or the same top speed. They are just similar performance. Which they are. More than they even have been.

[tomcug]

Originally Posted by Adam43

It’s not that simple and BoP isn’t about matching the top speeds.

It's not but when your rivals have big big straight line advantage on a track where straight line performance is king... sorry, you're a sitting duck. So for this track this is crucial for them to balance this decently.

[Articus]

Originally Posted by tomcug

All are brand new designs:
https://www.multimatic.com/press/mul...e-porsche-963/

That's interesting. In that case, what were they thinking...

[Adam43]

Originally Posted by tomcug

It's not but when your rivals have big big straight line advantage on a track where straight line performance is king... sorry, you're a sitting duck. So for this track this is crucial for them to balance this decently.

What is “decently”?

And how would they compensate the other aspects of performance? You’ve just increased the top speed of some (or decreased the others) - now you’ve got cars that are no longer overall in the same performance window.

Be careful of unintended consequences.

[chernaudi]

Here's the relevant 4:1 downforce to drag rule stated in the ACO's 2021 regs:

"3.8.3 Criteria
The aerodynamic coefficients must fulfil the following criteria regardless of the car attitude (examples, but not limited to: front ride height, rear ride height, steer, roll and yaw):

1. Downforce criterion ClAmax = 5.20 m2
2. Efficiency criterion ?max = 4.00
3. Drag criterion CdAmin = 1.00 m"

[chernaudi]

And now I have to make a double post to post further points without it looking/acting weird when I do it.


It should be noted, however, in the subsequent versions (at least in English), the appendix that this information appears in isn't featured in the ACO's or FIA's technical regulations PDFs (speculation is that it's intended for the ACOs/FIA's and teams' eyes only, not the general public--NASCAR has done their same with their whole rulebook, where it's supposedly available to the public now, but you still have to jump though hoops to actually get to it on their site).



But the idea as well as having a minimal frontal area of 1.6 square meters is obvious--to cut costs of and reduce the incentive for significant aerodynamic development. And aero, fight for lightweight and hybrid systems were the biggest cost killers in the last LMP1 regs.


And this gripe isn't strictly related to BOP in and of itself, but it's about parity (the principal that BOP is supposed to help enforce). I do hope that the ACO, be it with BOP or the whole pursuit of parity doesn't go down the NASCAR path, where in which they make the cars so equal in almost every way that passing is way more difficult than it is, and you run into the law of diminishing returns.


Namely, even though the gaps on the stopwatch narrow, nevertheless a wall gets formed due to the advantage that the "haves" have over the "have nots" becomes almost insurmountable, and costs more in terms of money, time and energy to overcome.


Ironically, when applied properly, BOP can side-step this, but again only when done properly.

[Adam43]

What is acceptable here? What do we need this to be?

If you make the top speed the same, will you then make everything else the same? You’ll have to otherwise you’ve ruined the rest of the BoP.

Edit:

My point is that this could be too much messing.
We aren’t clear on the consequences of doing it either, or what should be achieved.