WEC (World Endurance Championship) 2014

[Pierce89]

There is the K-factor in the calculations. This was discussed a while ago in this thread.

The K-factor was for fuel differences IMO. Do you have a quote saying it was for engine weight?

No, but the diesel got slightly more energy to make up for the weight. That's the whole point of these sets. Besides, in the real world, diesels don't get to run at the same overall weight at petrol cars, at Le Mans, diesels get an artificial level of assistance IMHO.

tthe k factor makes up for differenrces including diesels extra weight. The fuel technology factor is what balanced power.

Oh well, there's a fuel factor and tech factor. Its complicated, but the diesel is not at a disadvantage. As everyone already knows,VAG runs the ACO, so neither the Audi or Porsche will be disadvantaged. In fact, I expect Toyota will be pegged back now to make sure a VAG car wins the WEC.

[WhiteBlue]

Yes the k and t factors are meant to make up for a diesel's extra weight or any field of difference between different engines.. WB, you're normally well informed, but I think you should probably look through the WEC regs again before making a y more assertions

The table machin presented did not tell the same story. If they intended the k-factor to compensate for engine weight they did not implement that correction. So there is still a disadvantage for diesel IMO.

[Pierce89]

Yes the k and t factors are meant to make up for a diesel's extra weight or any field of difference between different engines.. WB, you're normally well informed, but I think you should probably look through the WEC regs again before making a y more assertions

The table machin presented did not tell the same story. If they intended the k-factor to compensate for engine weight they did not implement that correction. So there is still a disadvantage for diesel IMO.

Maybe so, good, diesel had an unfair advantage for years.

Edit: How is a diesel running at the same overall weight disadvantaged. In the real world, diesels are always heavier, so they're giving diesel an advantage by allowing to run at the same weight. Not to mention, that at equal HP, the diesel will have a torque advantage.

[langwadt]

Yes the k and t factors are meant to make up for a diesel's extra weight or any field of difference between different engines.. WB, you're normally well informed, but I think you should probably look through the WEC regs again before making a y more assertions

The table machin presented did not tell the same story. If they intended the k-factor to compensate for engine weight they did not implement that correction. So there is still a disadvantage for diesel IMO.

Maybe so, good, diesel had an unfair advantage for years.

Edit: How is a diesel running at the same overall weight disadvantaged. In the real world, diesels are always heavier, so they're giving diesel an advantage by allowing to run at the same weight. Not to mention, that at equal HP, the diesel will have a torque advantage.

how is the same total weight and heavier engine is an advantage? it means you have less freedom to move around ballast
how is higher torque an advantage? it just means you need a beefier clutch and gearbox

[machin]

The table machin presented did not tell the same story. If they intended the k-factor to compensate for engine weight they did not implement that correction. So there is still a disadvantage for diesel IMO.

Not quite right; My numbers showed that, due to the K-correction factor, a 2MJ Diesel is roughly equivalent in kinetic energy per lap terms to a 7 MJ Petrol Hybrid (i.e. faster than 6MJ, but slower than an 8MJ) AT LE MANS (but not at Spa/Silverstone where the 6MJ petrols have the advantage!)... however there appears to be a disparity in terms of stint length, where the 6MJ petrol appears to have a clear advantage over a 2MJ Diesel (assuming that all cars run at the minimum weight limit) at all tracks. My original posts:-

I think this is slightly odd.... Why "promote" (i.e give a bigger advantage to) the bigger Hybrid cars in the WEC, but not at Le Mans?

(Red is Diesel, Blue is Petrol)

The 2, 4, and 6MJ Diesels get relatively more fuel energy per lap in accordance with the "K-Factor" which balances the respective ICE weights... i.e. because the Diesel engine weighs more, they get more fuel energy per lap as a compensation...

I don't understand why the K-factor is 1 for 8MJ cars... as this implies that the engine weights are suddenly the same when you have the biggest hybrid system....

To my mind, this graph suggests that, due to the different engine weights, if we assume that all competitors will run at the 870kg limit, and run with the biggest hybrid system possible within that limit, a 2MJ Diesel is equivalent (in lap time terms) to a 6.5 to 7MJ Hybrid Petrol... which would be fair enough if that is what the ACO have determined... except we know that a 6MJ Petrol is "allowed" to do more laps on a single fuel tank (at max fuel consumption) than a 2MJ Diesel.... so there is no parity on that front...

????

[PorscheLMp1Fan]

These are from the ACO-FIA press conference at Spa.

[Pierce89]

how is the same total weight and heavier engine is an advantage? it means you have less freedom to move around ballast
how is higher torque an advantage? it just means you need a beefier clutch and gearbox

Dude the question is in relation to the fact that in the real world, there's not rules to equalize a diesels weight, it just creates a heavier car. Of course, we all understand the most basic principals of physics. As far as how is torque an advantage, have you ever pushed the throttle to the floor on an off boost turbo engine? Torque is good.

[Pierce89]

Nice chart, Porschefan

[machin]

As far as how is torque an advantage, have you ever pushed the throttle to the floor on an off boost turbo engine? Torque is good.

You don't mean Torque. what you mean is "mid-range power".

[WhiteBlue]

Machine’s table shows it very clearly. If we assume that the ACO made a perfect balance for a car without hybrid drive you see that they made the assumption the diesel manufacturers would design away the weight and weight distribution disadvantage of the heavier diesel engine.

Obviously this assumption is incorrect. Audi clearly planned to have a turbo generator powered hybrid 6 or 8 MJ system which they had to scrap because they could not take out the over weight to the degree the ACO had assumed.

And this is the core of my criticism. The T factor is not decided on actual performance data and design specifications but on assumptions that did not apply in reality. If we look at Machine’s table and pay attention to the history of the Audi design this is the only correct interpretation. So effectively Audi was forced by the regulations to run an underpowered car which developed lower performance and had to rely on attrition of the opposition to win the race on superior reliability.
To me this is not a correct balance of technologies and I think that Audi is entitled to a correction for next year, so that they can design a car that can competitively utilize the higher hybridization levels.

[machin]

http://d2uv4t0ox1pknx.cloudfront.net/fr ... .53.07.png

http://d2uv4t0ox1pknx.cloudfront.net/fr ... .36.46.png

http://d2uv4t0ox1pknx.cloudfront.net/fr ... .30.56.png

These are from the ACO-FIA press conference at Spa.

Because of the way the balancing works, a 2MJ diesel is only equivalent (roughly) in terms of lap time/kinetic energy to a 4MJ petrol at Spa.

At Le Mans a 2MJ diesel is equivalent to a 7MJ petrol (i.e. between a 6MJ and 8MJ petrol) in terms of lap time/kinetic energy per lap...

I don't know why the ACO did this... but the 6MJ petrols seem to get an advantage in the WEC compared to at Le Mans.... although in all races the 6MJ petrols should be able to do more laps (at max consumption) than a 2MJ diesel.

Here is my full table for Spa:-



Which compares to the Le Mans EoT table:-

[MadMatt]

Oh man all these numbers give me a head ache. Is it how racing is nowadays? I miss straight fights, pure racing.

[machin]

The "problem" with the above charts is that we have two performance characteristics (MJ/lap and stint length), which are both changing depending on the amount of Hybridisation, and that makes comparisons difficult.

if we were to "normalise" the MJ/lap by assuming that all cars will do 15 lap stints (i.e. those cars with less Hybridisation would need to do more fuel saving in order to do 15 laps), we end up with this chart, whereby the Diesels and Petrols are perfectly balanced (i.e. a 2MJ diesel = a 2MJ Petrol):-



I specifically chose 15 laps because this means that no car will break the maximum fuel flow per lap allowance.

To create this chart I have simply done:

((Max kinetic energy in fuel)/No. of laps per stint)+(Hybrid energy per lap x motor efficiency)

In this scenario the K-factor can be totally ignored....

[WhiteBlue]

To apply such a strategy and have a fair competition between petrol and diesel with regard to weight issues the minimum weight would have to be increased and the weight difference between petrol and diesel would have to be placed as ballast at the engine for petrol driven cars.

[djos]

If Audi want to put big fat heavy tractor motors in their cars that's their problem. Those using real car engines shouldn't be penalized for someone else's stupid decision!