Ford GT Mk2

[Jonnycoupe]

Might well be just about the braking performance and maintain consistency and excellent feel rather than something that varies the speed retardation depending on the battery temp ot state of charge and/or a complex brake blending system to balance friction and regen braking.

Braking is a key part of a making a fast car actually quick.

 

[Entai]

if that is correct this proves my points as to why it cant even do 1 lap of a long road or track without loosing power. its compromised. i bet adding the system that recharged it under braking added too much weight

It is not compromised in any way whatsoever in truth.

I have worked closely with Mclaren on the P1 project since inception, and know the actual true facts about the P1 when running around any race track.

Having worked with and spoken to the team that took the P1 to the Ring, I can tell you that the battery supplies full power throughout the whole lap of the Ring! It never runs out of juice!

In fact, during one lap the P1 is able to put almost as much charge back into the battery as they take out of it, so in fact it will run out of petrol way before it runs out of battery, especially around any race track.

 

[Entai]

So why did they exclude regenerative braking if it's effectively already equipped to do it?

Because they use a better system than regenerative braking.

 

[Kenai]

Because they use a better system than regenerative braking.

Well that's what I thought and then I get someone telling me it IS regenerative braking

 

[Simon]

Same principle. The battery gets charged without the need for plugging in.

 

[Kenai]

Really? I thought it had a lead plugged in everywhere it goes.

 

[Simon]

I’m confused about where we are going now. We have People in the thread who are saying hybrid supercars are pointless as they run out of battery as they don’t have regen braking.

This is obviously wrong.

We then get into silly details and completely off topic discussions.

 

[Kenai]

I originally just commented on the fact I didn't think the P1 had regenerative braking, which it doesn't, then just responded to the handful of posts trying to imply I was stupid for thinking this.

 

[Simon]

It just uses the engine as a generator so the battery never runs out. Ideal setup really for a performance driven car.

 

[Jumper118]

It is not compromised in any way whatsoever in truth.

I have worked closely with Mclaren on the P1 project since inception, and know the actual true facts about the P1 when running around any race track.

Having worked with and spoken to the team that took the P1 to the Ring, I can tell you that the battery supplies full power throughout the whole lap of the Ring! It never runs out of juice!

In fact, during one lap the P1 is able to put almost as much charge back into the battery as they take out of it, so in fact it will run out of petrol way before it runs out of battery, especially around any race track.

i find that very hard to believe. they wouldn't release any lap times or anything. i also very much doubt you can charge a battery as fast as you can drain it. i have seen what happens when you charge batteries too fast and it normally ends in things being on fire

 

[Jonnycoupe]

I googled it, it is due to brake feel as I suspected. Prevents the engine braking assisted by an electric motor (regenerative braking) corrupting the feel and consistancy of the mechanical friction brake system.

 

[Housey]

The complexity of modern cars and their sheer pace and competence does take something away for me. I get it’s progression, but still leaves me a bit cold.

 

[Entai]

i find that very hard to believe. they wouldn't release any lap times or anything. i also very much doubt you can charge a battery as fast as you can drain it. i have seen what happens when you charge batteries too fast and it normally ends in things being on fire

If you want the technical specs then here you go .

The electric energy needed for the electric motor to deliver it's 176 hp boost is roughly 140kW. The batteries in a P1 store approx 3.4kWh of energy. therefore, the electric motor could be powered at full for 87 seconds, presuming you can find a long enough stretch of road to be at full throttle for 87seconds, (3.4kWh / 140kW = 0.024h = 87secs)

Within those 87s clearly the P1 can easily reach top speed, so once at top speed the P1 does not need its full engine and electric motor boost to sustain said top speed, so the ECU will then reduce torque of the electric motor to 0, but it also needs to increase the torque of the engine to compensate a little, which it can, so vMax is maintained without the use of the electric motor.

To recharge the battery, just like most other hybrids, the P1 uses the electric motor as a generator.

As a generator the engine, (depending on the RPM applied to it by the ECU), can produce as little as a couple kW all the way up to roughly 120kW, (often limited to around 100kw, especially when braking to reduce the engine braking effect felt) Which would mean, at max kW it would take 3.4kWh / 120kW = 102secs to fully recharge the battery.

If you drive at a steady speed, and steady throttle position, the ECU will turn off the electric motor, (as it is not needed in that scenario) then it will increase the engine torque and revs slightly and through 3 sets of clutches, apply that extra torque to the electric motor, which will in turn generate energy to charge the battery.

When driving a P1 you will notice this as the engine will start to rev slightly higher, without you pressing the accelerator any harder, or the car speeding up, it's a little unnerving first couple of times, but you soon get used to it.