[noone1]

So, even if the Ring doesn't improve to what people want, what do you think the outcome is going to be on other famous/popular circuits between these three cars given what we know about the cars and their energy consumption/regeneration?

One point of interest was that the 918 was out of energy at the end, hence the lower speed. Was this a coincidence? How much energy would it get back and be able to use on lap two?

I'm wondering if the 918 made it through more of the lap do to it's battery size or because of it's regeneration capabilities. Is the 918 a heavy net consumer of energy that once depleted is going to be out of power more often than not?

We know the P1 went from full to empty twice during it's lap, or so they said, implying that it was actually able to use and replenish all it's energy, while still turning in what is at least the 7:04 lap time.

Are the shorter circuits going to show massively different results than the Ring?

 

[Minnesota]

I think right now there is alot of speculation, and people don't really know what the outcome of running the cars around a track lap after lap will be. Some of the speculation is that the LaF will be at an advantage because a smaller percentage of its horsepower is tied up in the electric system and its thought to be the lightest, the theory being that once the car is out of juice it will have the best power/weight ratio. And there is speculation that the P1 will be at a disadvantage due to its lack of using regenerative braking. And the lack of using brake regen does seem like a disadvantage to the P1 but ... I don't think anybody exactly knows right now.

Also, it isn't known that McLaren's P1 is maxed out at a 7:04, it isn't known that its ride height is too low for the 'ring, and so on. Its all just a bunch of blind to very educated (depending on which guess and who posts it) guesses at this piont, I believe.

It is known that the 918 has a "hot lap" function which drains its batteries and another function which maintains a certain state of charge in them. This may give the 918 some, unsustainable, advantage for a single lap. It does not appear that LaF or the P1 have this function.

There are some loose statements out about the P1s lap time. That it will be fastest at Dunsfold (the Top Gear) track, although the comment that it will break the record by 10 seconds wasn't made, what WAS said was a joke, about how Ron Dennis could drive the P1 10 seconds faster than the record for a star in a cheap car... Some of the rumors are 20 seconds faster around Silverstone than any production car to date (3.7 miles). Fastest laps lists the record as 2:08 in a Lambo SV. 5 seconds faster than a gt3 car at Spa and so forth.

I wouldn't bet that the story of the P1 at the 'ring is finished.

 

[jkheit]

This really brings up a really interesting philosphical question for hybrids. What is the *real* HP. On one extreme, if the battery provides boost to 3000HP for 1second, that is *not*, IMO, a 3000HP car. It's more like a shot of nitrous. If the battery charge lasts as long or longer than the gas tank, then I think it's easy to say the car is a 3000HP car.

So all the current supercar hybrids are somewhere in between. And I think it's fair to say if they all last only long enough for one lap at a track (or thereabouts) the "extra" HP is a bit more of a nitrous gimmick than a real add to HP.

Now perhaps the Regen abilities keep some amount of extra boost/juice going to the car, but it's interesting as to how much.

So a good example would be something like a 24hr lemans type event. What is the average, or perhaps more accurately, **sustained**, boost provided by the electric motors. Perhaps on the P1 it averages out to only 25hp, perhaps on the 918 its 50hp. There needs to be some kind of standard to know what is the continuous and sustained electric engine HP that gets fed to the car vs the nitrous like boost level.

 

[Minnesota]

jkheit,

That was a nice post and set of thoughts. For example it is known that the 918 spyder loses a chunk of its total power output above 140x mph when the front e-motors decouple. But it isn't known how much of its total hp would be available in "race hybrid" mode which I believe doesn't deplete the charge, on average, around a lap.

From what we've seen, so far it looks like the P1 and LaF always operate in some equivalent of "Race Hybrid" mode without a "hot lap" function to deplete the batteries. It seems certain that the power output of all 3 cars is overstated relative to an equivalent pure petrol engined car ...

 

[zippycar]

Isn’t this the sort of informed/considered discussion we have sadly been missing of late?

My issue with the 918 is weight and power.

How can a car with less power and more weight than the P1 get a better time around the Ring, irrespective of technology?

It seems to defy physics, but then, I did fail my A-level Physics!!

 

[DLC]

Isn’t this the sort of informed/considered discussion we have sadly been missing of late?

My issue with the 918 is weight and power.

How can a car with less power and more weight than the P1 get a better time around the Ring, irrespective of technology?

It seems to defy physics, but then, I did fail my A-level Physics!!

Yes it is.

I'm with you on the physics examination. Add another attribute P1 beholds that 918 is short on, aerodynamic downforce. On paper it looks like 918 shouldn't be in the same league and I think we will eventually find out that it isn't.

 

[jkheit]

Minn, the cars are so complex as to when and how they ally force, you need a degree in automotive engineering just to keep track.

Zippy, I think the gtr shows you can do some nice things with heavier cars, and the 918 numbers seem to show the same. Interesting in how that translates into "flickabity".

 

[Minnesota]

Yes it is.

I'm with you on the physics examination. Add another attribute P1 beholds that 918 is short on, aerodynamic downforce. On paper it looks like 918 shouldn't be in the same league and I think we will eventually find out that it isn't.

And the thing is... if we assume that the P1 cannot ride at its low height over the ring for some reason, would it not still have more downforce than a 918? And even if we assume that its electric engine can only manage a total of about 1/3 of peak output over a lap of the ring, we'd still have a similar power/weight ratio to the 918. With presumably more downforce and less weight. Tires could vary, of course, and the 918 has AWD and more torque vectoring, but I'm suspecting a better time will be released for the P1. Possibly alot better.

 

[DLC]

And the thing is... if we assume that the P1 cannot ride at its low height over the ring for some reason, would it not still have more downforce than a 918? And even if we assume that its electric engine can only manage a total of about 1/3 of peak output over a lap of the ring, we'd still have a similar power/weight ratio to the 918. With presumably more downforce and less weight. Tires could vary, of course, and the 918 has AWD and more torque vectoring, but I'm suspecting a better time will be released for the P1. Possibly alot better.

That's what I'm thinking. Important to remember is that all the posters commenting and speculating on what the problems are with this car are basing those comments on "rumors" of a P1 ring time of 7.04. McLaren will post a ring time. If they post 7.04 or some other non competitive time, then those comments and posts become relevant. Until then, those discussions are pointless IMO. I haven't seen any sound information that would lead me to believe it won't be the car McLaren has advertised. P1 has all the physical tools and McLaren is a racing company first. I have confidence they will get this right when all said and done. These special cars come around every 10-20 years in the life of these manufactures so this is an important venture for their future success.