Rally Discussion and Bar Talk Thread

[saco0o]

https://youtu.be/Cae2haI-zmY?feature=shared

Could you guys imagine something like this rallying before the end of this decade?

this is like if astrology could have a physical body. it serves no porpouse other than fool desperate people haha jeez

[saco0o]

Richard Millener really struggled to explain the merits of having hybrid units on Rally1 cars in a chat with Dirtfish.

I got the feeling that marketing and imaging were getting in the way of their core business of selling customer cars!!!!

https://dirtfish.com/rally/wrc/did-s...hybrid-in-wrc/

i think his point could be right, on the "on technical rallies, the differences would be bigger". it'd be cool if they run one non hybrid at one of these events, but with someone like Loeb, so we coudl actually see what a good driver can do against the hy cars. but imo the general point is that, as they said, the non hy car looks awesome both live and on tv and it would cost half of the price. and if you remove those extra 100kg they would be faster. fine, it would be dangerous, so, idk, keep 50kg for safety, whatever. the last point would be: "would we have more teams and privateers?

[mknight]

Because it is impossible and nonsense...

When faced with numbers and real arguments this is the perfect response.

[Eli]

this is like if astrology could have a physical body. it serves no porpouse other than fool desperate people haha jeez

Just so we’re clear, I hope they don’t and I can’t (imagine it).

[mknight]

https://youtu.be/Cae2haI-zmY?feature=shared

Could you guys imagine something like this rallying before the end of this decade?

Totally.

The only real issue with electric rally cars is the lack of noise, especially at low speeds. Both for "entertainment", safety and to hear what the driver is actually doing (braking/acceleration).

So sound generator dictated by rules would be mandatory. Consumer electric cars already have it for low speeds.

The only version I heard from Paddons car sounded weird. But maybe it is better live. Taycan artificial sound is quite good live for example.

The big question is whether you need to have artificial gears like that mode in Ioniq 5N. If so it could again be set in the rules.

[WRCStan]

https://youtu.be/Cae2haI-zmY?feature=shared

Could you guys imagine something like this rallying before the end of this decade?

Sure, the non-N can now so why not?

Of course, it may depend on what you accept as rallying.

[WRCStan]

The big question is whether you need to have artificial gears like that mode in Ioniq 5N. If so it could again be set in the rules.

The bigger question is who's buying them, and are we likely to be seeing these at all at the end of this decade.

[saco0o]

another thought I had reading the dirt fish article with msport about the non hybrid car. he said that evs went on a high (sells? perception?) and now are declining and hybrids are going up. at the same time is super normal to find daily articles on how much evs are growing (in sells and perception) passing hybrids for new cars. u'know? we can find both arguments nowadays. its such a mess. we probably can find data showing how both evs and hybrids are outselling each other on the same journal. everything is so weird and contradictory nowadays, all the time.

[Mirek]

Why do you keep repeating this when it is clearly wrong?

Current technology EVs can do the current WRC stages just fine. Refueling zones are set up completely arbitrary and have no effect on spectator experience.

At the extreme you could do 10 min charges at the end of each stage. With current gaps that would mean 4 cars charging at the same time. Lets say they charge at 360 kw which is mainstream tech today and you get 60 kwh charged. That is enough for 150 km road section minimum or a normal stage and some 50 km road section.

If you have 10 cars total in top class the charging station would need some 700 kwh capacity total, should be roughly 2-3t. So the charging station could be on a small truck, no need for trailer.

I say again why do you keep repeating that this is impossible?

I have never said an EV rally car can not do a rally loop distance. The problem is that it can not be competitive to WRC cars at the same time.

Let's say you take a car with 60 kWh battery. That is about 250 kg without cooling. What percentage of the energy can be recuperated in rallying? Formula-E does about 40% but that is impossible in rallying, especially on gravel. Let's say it can be 20%. That means you have realistically 1,2 * 60 =72 kWh. How far can WRC go with 72 kWh (I count the powertrain to have 100% efficiency for simplification)? Hard to say but we can simplify the question by setting the loop as long as a petrol tank allows. Just for comparison.

If we go by the petrol Rally2 cars (to avoid the effect of hybrid which is too complex to estimate) we can count that 80 litres equals 60 kg of petrol which is 780 kWh of energy. The petrol engine has much lower efficiency. How much? An average turbocharged petrol engine has about 40%. WRC engine will have probably less due to the use of anti-lag and also the mechanical drivetrain is less efficient. Let's say that it's total 25% which might be too low. That means the Rally2 car in my example has 195 kWh of usable energy available. How much does en empty rally fuel tank weight? I don't know but it's a soft bag. Let's put it filled at 100 kg which might even be too much. The racing battery needs massive cooling otherwise it can not discharge and recharge high power. In formula-E the battery alone creates about 60% of the battery pack total weight, that makes our battery pack about 400 kg heavy and it contains about 1/3 of usable energy compared to the fuel tank of the Rally2 car which is 4x lighter.


If we use the same average power with both cars (I counted the effect of recuperation into usable energy value already) we need in theory more than 3x total battery capacity for one fuel tank. What C-rate is used for race battery charging? I don't know. Normally the very best batteries allow 4C not to damage the battery but that applies only for 20-80% of the charge level, not for 0-100%. That would destroy the battery. It means we can use only 60% of the battery capacity for the fastest charging. That is only 36 kWh available for the fastest charging. The good thing is that with 4C you can recharge that in 9 minutes which looks great. The bad thing is that 3x quick recharging is not enough to finish the loop a fully-filled petrol rally2 car can finish.

But that's not all. As we saw our EV has 300 kg extra weight for the 60kWh battery. It will definitely need to deliver more power than the Rally2 to be as fast. In fact it will need a lot more because its weight will punish it badly in cornering speed and maybe even in braking (the recuperation will help here but I don't know if enough). This hypothetical example fits with the reality where an EV Rally2 car with similar battery to my example was clearly slower than the Rally2 cars.

But the worst thing is that this example compared with Rally2 not with WRC. WRC cars are about 2 s/km faster than Rally2 which means that among other things they need a lot more power. The equation to give them enough energy onboard in batteries to allow them to be so powerfull to overcome the weight punishment coming with the larger battery is unsolvable at the current tech level, at least at some realistic price tag.

Hence why I repeat my stance that the only way how to make EV competitive in rallying at the currect tech level is to give them an energy source with far greater density - in serial hybrid it's the petrol which carries about 50x more energy per kg than the best batteries. Anyway Audi won Dakar while the pure EVs have achieved exactly nothing in rallying.

PS I am well aware that there is a lot of guessing in my post but a mistake in the range of 10-20% doesn't change the resume.

[becher]

I don't see why recuperation would be a performance benefit, the limiting factor under braking is grip not power of the brakes no?