Rally1 hybrid cars (2022-)

[Mirek]

Re the regen by braking...

When a driver brakes sufficiently hard does the regen system then activate to slow the car, partially slow the car, or do the brakes & pads still do all the stopping ?

The regen of course slows down the car, it can not work other way according to the laws of physics (you take away the kinetic energy of the car and transform it into electricity). It helps to the brakes because you don't need that much braking power from the brakes alone (and therefore you also don't heat them that much).

When you drive an EV you don't need brakes at all for common gentle braking.

[Fast Eddie WRC]

The regen of course slows down the car, it can not work other way according to the laws of physics (you take away the kinetic energy of the car and transform it into electricity). It helps to the brakes because you don't need that much braking power from the brakes alone (and therefore you also don't heat them that much).

When you drive an EV you don't need brakes at all for common gentle braking.

I heard the new Audi e-Tron running at the Dakar can do the whole event on one set of brake pads. I daresay the Rally1 cars will be much lighter on brake wear too.

[Mirek]

and for the boost time. the 3.9kWh can boost for 2.5 minutes with 100kw .so if there have the long long straight during the stage.will the driver make the boost as long as possible or they will touch the brake to end boost to save the energy

There are limits set for each stage by the FIA for how much energy can be used in one boost before having to regen, the regen is also a minimum FIA set limit to recover. We don't know what they are yet to have a meaningful answer.

Not only that. It also doesn't make sense from technical point of view. The time to reach the top speed from standstill is probably around 15 seconds. You don't need any extra boost to keep the top speed.

[Mirek]

I heard the new Audi e-Tron running at the Dakar can do the whole event on one set of brake pads. I daresay the Rally1 cars will be much lighter on brake wear too.

I'm known as a no fan of EVs here on the forum but this is actually a great thing because one of the major sources of polution caused by the vehicle traffic is the dust from the brake pads.

[Sulland]

Thinking reliability, especially in the beginning of the season.
If the hybrid pack stops working, can drivers continue at topspeed from the ICE without any damage?
Any other bits and pieces that are new, that represent reliability risk?

[RS]

I heard the new Audi e-Tron running at the Dakar can do the whole event on one set of brake pads. I daresay the Rally1 cars will be much lighter on brake wear too.

The next generation Formula E car has no conventional rear brakes at all (regen only)

[kubiczech]

But of course the recuperation adds a lot of energy. We don't know what recharging power can be used in WRC cars but a heavy braking produces much higher power than the extra boost, which means that the time spend on braking to recharge the energy is not long.

Wrcwings says:
f) the recuperation by braking is limited to 30kW, no matter how hard a driver brakes,


https://www.wrcwings.tech/2021/09/14...-implications/

[AnttiL]

Thinking reliability, especially in the beginning of the season.
If the hybrid pack stops working, can drivers continue at topspeed from the ICE without any damage?
Any other bits and pieces that are new, that represent reliability risk?

Yes they can disconnect the unit but they will lose the power boost.

[WRCStan]

thanks for your details explain
so from my understanding the each boost power is the same 100 kw no matter what stage .but the each boost time should be decide by the FIA for different stage (like 6 seconds for short stage and
3 seconds for longer stage unless take the brake earlier ),but I believe each boost time can't be longer than 10 seconds

I'm glad you ask actually because you are making me think about this. Here's my understanding and if I get it wrong hopefully a pro engineer will correct us.

My understanding is the power is maximum 100kw, so in purely electric motor mode the throttle pedal may relate 0-100% of 100kw. But when combined with the ICE engine, which has it's own torque curve through revs, you might not necessarily want that linear throttle pedal to electric motor relationship. Then there is surface traction and driving style to think about.

The teams have three torque demand maps to set before the season starts, but can change these once this season. The ICE has it's own demand map too to consider (it isn't linear). The drivers can choose one of these new electric motor maps before each stage. These are mapping the power output of the electric motor to the throttle pedal position (driver's demand) (and/or maybe the engine output I'm not sure). They may want 100% electric power by half the pedal, or only start from half way, they may choose only 100% motor at 100% pedal and nothing else. The point is there are 3 strategies for the team to play with. Tom Fowler at Toyota said it'll be likely based on surface type. You can wheelspin on gravel if you go full whack early or you could get a grippy launch on dry asphalt. https://dirtfish.com/rally/wrc/how-t...ost-will-work/

The FIA will determine only energy limits for on-stage boosts per stage, so it's not time. This might be more than the 1000kj given for the launch boost. I assumed everybody will launch at 100% power earlier and maybe I misunderstood your question, so given the torque maps, they may use half the power for twice as long, who knows.

If the FIA give a small deployment energy limit, what is the point in the battery capacity other than the 5km of emission free driving. If they give large amounts, then why cancel it at smidgen of brake and force another regen. Likely then, the regen will be smaller than the deployment limit. Difficult to wrap my head around at this point and I'd hoped these limits were made public for us nerds.

[becher]

There has been comments from drivers about the switch to "stick shift" and the potential to damage the gearbox. As far as I undrstand, they will still be running a sequentiel dogbox, and only got rid of a fairly "simple" hydraulic system to actuate the gearbox. If my understanding of the regulations is correct, how would that be a significant cost saving like the FIA claims and how would one be able to damage the gearbox any more than with a paddle actuated gearbox?