What if somebody built a faster lapping road car?

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beelsebob
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Re: What if somebody built a faster lapping road car?

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Ogami musashi wrote:
beelsebob wrote: Okay, and? The downforce generation on an F1 car is extremely limited.
No. The fact that aero regs are indeed far more strict than before doesn't mean the production of downforce is limited.
It means the easiest ways are forbidden.
Uhh no, it means it's limited, there is an upper limit to the amount of downforce it is possible to produce given the areas allowed to be used, and the profiles alowed to be used. Are F1 teams at it? Absolutely not. Are F1 teams near it? Certainly, they're probably within 3 9s of it for the top teams. The bottom line is, given free reign, you can produce more downforce, no questions asked.
The P1's diffuser is bigger than the entire diffuser and rear wing structure of an F1 car alone. The rear wing on a P1 is 4 times the size of the rear wing on an F1 car. I would bet heavily that it too would produce more than its own weight in downforce at 150km/h (probably significantly earlier).
First, if the size of a diffuser was equal to production of downforce then WSR 3.5, GP2's, indy car, FN cars would produce more downforce than F1...which is not the case. Downforce generation by the diffuser is largely dependent on the feed flow which is conditionned by bodywork and front and rear wing couplages...which is precisely where an F1 car is above the rest.[/quote]
No, the reason that these cars don't produce that level of downforce is because they're inherently compromised, just like an F1 car. Is an Indy car allowed to move it's rear wing? No... So it's downforce generation is traded off with its top speed, and the teams choose to go for top speed given the oval nature of the tracks involved.
Next you seem to forget a bit that downforce alone is not relevant, downforce to weight is....Which brings me an answer to your wonderings: No the P1 won't produce its weight in downforce at 150km/h for its mclaren themself that said the car would have similar downforce level as the MP4-12C GT3 racer...which is far from producing so much downforce.
Do you have a link for this claim? The claim I can find McLaren making is "The new McLaren P1 has much higher levels of downforce than any current road car – 600kg is achieved well below maximum speed. That is approximately five times as much downforce as a McLaren 12C." That's an F1 car's total weight at "well below top speed" – it's entirely reasonable to suppose that means it's generating more downforce than an F1 car, as we're talking "well below top speed" (reasonably, we're talking about 150km/h ranges then), and the entire weight of an F1 car generated.
Which is great, but not that useful in early acceleration, what you need there is even application of power so that the wheels are applying maximum force to the road surface, and not slipping. Traction control will make the P1, along with many other road cars beat an F1 car off the line, or out of corners easily.
When you corner at 200km/h average, traction is not the limiting factor in accelerating but power/drag is.
I think you are a bit dreaming at thinking a car with half the power/weight ratios, on grooved tyres can beat an F1 car off the line.
The point being that an F1 car doesn't corner at 200km/h average at monaco – note, my assertion was that this car might beat an F1 car round a twisty turny circuit, not that it would beat it round a high downforce circuit like Spain.
What makes you think aero stability is an issue on a car designed by a top F1 team?
Because aero stability is inherently harder with full bodywork cars for you can't direct airflows as well as with open wheelers and because the suspension geometry of Gt cars make load transferts have greater effect on car attitude than open wheelers.
But at the same time, the fact that the wheels are enclosed means you don't have enormous rotating masses kicking up huge amounts of turbulance, and moving in the air flow, causing the air flow behind them to change massively when you steer.
The P1 gets to have significantly bigger brakes than an F1 car is allowed, meaning more contact area, meaning more force at lower pressures. Add to that that the movable rear wing will almost certainly be positionable to act as an aero brake, and you're looking at some pretty huge braking forces. Open wheelers don't have any inherent advantages these days, in fact, they have significant aero disadvantages.
You again seem to forget that bigger brakes are there because the car is bigger and heavier; Plus braking force is due to tyre's grip not disks size.[/quot]
No, I don't forget that at all – F1's high braking forces are down to two things 1) super sticky tyres 2) super fancy breaks. The aero break compensates for 1 (as it doesn't require friction with the road, only with the air), the large disks compensate for 2 as the higher surface area allows more braking force to be generated despite lower brake pressures.
Next the airflow conditioning on the rear wing of GT/closed cockpit lmp style car is much worse than an open wheeler. And conversly the drag on the open wheeler rear wing is much greater and is the major reason why drag on open wheeler is so high.
Which is why when Newey was asked to design a concept car for how F1 might be if the rules weren't so strict, he designed a closed wheeler... wait.
Group C existed in 1982, way before any significant understanding of movable aerodynamic devices, skirts, under-body aero, diffusers, electronically controlled suspension, traction control, etc existed. The P1 will be trivially faster than Group C.
Hum..Group C existed all the way to 1992 where you had the F3.5 cars (peugeot 905, Toyota TS10) which produced massive amount of downforce (up to 6 tons at 320km/h); they also had more top speed than F1 cars, yet couldn't beat them and i'm talking about F1 cars that were far from the speed of the current ones.
And yet, in 1992, we were still a year or two away from Williams developing even the most rudimentary of active suspension systems.

Nando
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Re: What if somebody built a faster lapping road car?

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bucker wrote:Mp12-4c is 16 seconds slower on top gear test rack. F1 car did it in 59s, mp12-4c in 1.16.xx and this is a short lap. Gap between times increase if the track is longer. There is no way that super or hyper cars can be faster than F1 cars.
Sorry for being anal here but it´s MP4-12c :)
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beelsebob
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Re: What if somebody built a faster lapping road car?

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bucker wrote:Mp12-4c is 16 seconds slower on top gear test rack. F1 car did it in 59s, mp12-4c in 1.16.xx and this is a short lap. Gap between times increase if the track is longer. There is no way that super or hyper cars can be faster than F1 cars.
An MP4-12C is barely even a super car, let alone a hyper car.

Ogami musashi
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Re: What if somebody built a faster lapping road car?

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beelsebob wrote: Uhh no, it means it's limited, there is an upper limit to the amount of downforce it is possible to produce given the areas allowed to be used, and the profiles alowed to be used.
There's no limit on profiles; Neither are on the areas, nor cascade; Just maximum volumes; Given that you have still a lot of room.



No, the reason that these cars don't produce that level of downforce is because they're inherently compromised, just like an F1 car. Is an Indy car allowed to move it's rear wing? No... So it's downforce generation is traded off with its top speed, and the teams choose to go for top speed given the oval nature of the tracks involved.
You said the P1 has a bigger diffuser so produces more downforce than an F1 car; This is wrong to assess the size of a diffuser is directly related to amount of downforce without taking into account the size and weight of the car and the way the air flows into it.
The reasons why FN GP2, WSR and indy cars do not produce as much downforce (and that was the same for the champ cars of 2007 despite being road only cars.) is because they are allowed to be optimized on flowfields like F1 yet they have full length venturi tunnels.


Do you have a link for this claim?
Yes: http://www.ultimatecarpage.com/car/5292/McLaren-P1.html

See:

"The McLaren P1's downforce is similar to current sports racing cars, including the 12C GT3 racer"

"On the race track, the McLaren P1 would display similar levels of performance to a Le Mans sports racer, thanks to its aerodynamic shape,"

"racing car-like track performance from a road car"
 it's entirely reasonable to suppose that means it's generating more downforce than an F1 car, as we're talking "well below top speed" (reasonably, we're talking about 150km/h ranges then), and the entire weight of an F1 car generated.
No it's not, and you have no proof that this is generating thoe 600KG at 150km/h, and you still seem to struggle with the fact that even if it was producing 600kg of downforce at those speeds (very unlikely) the car weigthing at least 2 times the weight of an F1 car you still have much less grip.


The point being that an F1 car doesn't corner at 200km/h average at monaco – note, my assertion was that this car might beat an F1 car round a twisty turny circuit, not that it would beat it round a high downforce circuit like Spain.
At monaco the average speed is 160km/h. This is a speed at which an F1 car already produces more downforce that its weight, and this is also a speed at which power/drag ratio is important.

But at the same time, the fact that the wheels are enclosed means you don't have enormous rotating masses kicking up huge amounts of turbulance, and moving in the air flow, causing the air flow behind them to change massively when you steer.
True wheels do disturb the flows, but why do you think F1 tires have slip angles as low as 3°? and the advantages of open wheelers (I.E: single seaters) is not there, but in the lower wetted surface as well as the flow conditionners that are far easier to place (just see developpement of sidepods, vanes and barge boards...impossible to do to that extent on GT cars).

No, I don't forget that at all – F1's high braking forces are down to two things 1) super sticky tyres 2) super fancy breaks. The aero break compensates for 1 (as it doesn't require friction with the road, only with the air), the large disks compensate for 2 as the higher surface area allows more braking force to be generated despite lower brake pressures.
Man...brake disks impart slowing torque on the wheel that must transmit it to the ground...if you don't have traction you can have the largest disk out there.. and aero brakes work at high speed.
Now this doesn't change the fact that with a bigger and heavier car you need bigger disk, so that still doesn't make your point.

Which is why when Newey was asked to design a concept car for how F1 might be if the rules weren't so strict, he designed a closed wheeler... wait.
He designed a single seater with enclosed wheels; not an intergral GT....And if you followed the technical description of that concept the car is full of flow conditionners.


And yet, in 1992, we were still a year or two away from Williams developing even the most rudimentary of active suspension systems.
You are pretending a road car can produce as much downforce as an F1 car, proclaming some vagues arguments that lack a bit of physics ground there; To prevent entering too much into details i quoted you race cars that did have more downforce/weight than F1 cars yet because of several structural and bodywork reasons were still slower.

Now you have Mclaren automotive itself telling you that the car is aimed at having the same level of downforce as a GT3 car, a GT3 car is far from being as fast as an F1 car...and still has features that the P1 won't have (sticky race tires, race suspension and chassis, lighter weight) so how can you imagine this car would beat a car that is designed to be at the forefront of quickness around a track???

To end up with this, every car has constraints; The fact that the P1 is a road car, twin seater is already a big one. There's no such thing as a "free design".

Ferrari did the same trick with the 599XX and its fans assited ground effects, the car is still miles away from an F1 car's pace.

beelsebob
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Re: What if somebody built a faster lapping road car?

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Ogami musashi wrote:
beelsebob wrote: Uhh no, it means it's limited, there is an upper limit to the amount of downforce it is possible to produce given the areas allowed to be used, and the profiles alowed to be used.
There's no limit on profiles; Neither are on the areas, nor cascade; Just maximum volumes; Given that you have still a lot of room.
Go back and read rule 3.10 of the technical regulations. Then we'll have this discussion again.
No, the reason that these cars don't produce that level of downforce is because they're inherently compromised, just like an F1 car. Is an Indy car allowed to move it's rear wing? No... So it's downforce generation is traded off with its top speed, and the teams choose to go for top speed given the oval nature of the tracks involved.
You said the P1 has a bigger diffuser so produces more downforce than an F1 car;
No I didn't – I asserted that it entirely reasonably could, when it was asserted that it couldn't produce anywhere near. It appears from McLaren's own comments that it indeed does produce very similar levels of downforce to an F1 car, but with a heavier car weight.
 it's entirely reasonable to suppose that means it's generating more downforce than an F1 car, as we're talking "well below top speed" (reasonably, we're talking about 150km/h ranges then), and the entire weight of an F1 car generated.
No it's not, and you have no proof that this is generating thoe 600KG at 150km/h, and you still seem to struggle with the fact that even if it was producing 600kg of downforce at those speeds (very unlikely)
Where by "very unlikely" you mean "pretty much exactly what McLaren said.
the car weigthing at least 2 times the weight of an F1 car you still have much less grip.
Actually, you'd have more grip due to the increased downward force of aero downforce + weight combined, but also more centripetal acceleration required based on that grip.
The point being that an F1 car doesn't corner at 200km/h average at monaco – note, my assertion was that this car might beat an F1 car round a twisty turny circuit, not that it would beat it round a high downforce circuit like Spain.
At monaco the average speed is 160km/h. This is a speed at which an F1 car already produces more downforce that its weight, and this is also a speed at which power/drag ratio is important.
Average speed of 160km/h implies average cornering speed significantly below that. And yes, power to drag is extremely important, which is why the movable aero will make such an important difference.

fiohaa
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Re: What if somebody built a faster lapping road car?

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beelsebob wrote:
Absolutelee wrote:On a real circuit a car without aerodynamics is going to get destroyed in the corners. Also, road cars are so heavy.

The Ariel Atom is one of the fastest street legal cars available and it does 0-60 in 2.8s...I think I remember hearing F1 cars to 0-60-0 in 3s
It's actually pretty common for road cars to beat F1 cars off the line, simply because F1 cars are geared towards always maintaining a speed over 60mph even in the very tight turns. I once saw a test at silverstone where they raced an F1 car and a porche 911 off the line – the 911 initially accelerated (by eye) twice as fast as the F1 car, and in fact reached turn 1 (then copse) entry ahead by quite a margin. The F1 car though simply didn't slow down, while the porche breaked into copse, and by even mid corner was significantly ahead.
............lol.
is this a joke.

there is absolutely no way in hell that a 911 could still be ahead of the F1 car going into Copse, from the start/finish line. Absolutely no chance.

Make that 911 a new turbo. Make it a GT2. It would have no chance against any F1 car from the past 20 years.
you must have been viewing this from a very strange perspective.

youtube any video showing acceleration of an F1 car with times, and compare that to the manufacturer claims for the fastest car porsche makes. I'd imagine a GT2 or 4x4 Turbo would be faster from 0-60 by a few tenths. In the distance from the old start/finish straight at Silverstone to the entry point into Copse, the F1 car would be ahead...by at least a few seconds, it wouldnt even be close.

so i dont believe you at all, because of physics.

Blue fellow
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Re: What if somebody built a faster lapping road car?

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In regards to the McLaren's P1 downforce, it supposedly will generate 1300lbs at 125mph (590kg @ 201 km/h) according to this link

http://www.autoblog.com/2012/09/27/mcla ... aris-2012/

markp
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Re: What if somebody built a faster lapping road car?

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Tyres? Roadcar has to last thousands of miles an F1 car about 100 miles per set. To produce the grip the road car tyres would have to be alot softer if they can do thousands of miles and generate same grip as F1 F1 would use them. If they were softer they could not handle corner lads of F1 which has far harder tyres. If roadcar used F1 compounds the suspension would have to change makeing it undriveable on the road .

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Re: What if somebody built a faster lapping road car?

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Rallycross Supercars claim to do 0-60mph slightly faster than an F1 car...

http://www.mallorypark.co.uk/index.php? ... &Itemid=84

..Whilst they're not "road cars" as such they do at least look like road cars and could feasibly have space for a passenger seat, and they do have "reasonable" ground clearance... but I can't see them being faster than an F1 car around any circuit other than a Rally superspecial....
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Ogami musashi
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Re: What if somebody built a faster lapping road car?

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beelsebob wrote: No I didn't – I asserted that it entirely reasonably could, when it was asserted that it couldn't produce anywhere near. It appears from McLaren's own comments that it indeed does produce very similar levels of downforce to an F1 car, but with a heavier car weight.
You're contradicting yourself in this very sentance...No...Mclaren never said such a thing and by the way you again forgot about the weight and dimensions. Cars that produce more downforce than F1 do exist..they are much larger and weight much more. There's a relationship between weight loading (weight/wetted surface) and downforce.


Where by "very unlikely" you mean "pretty much exactly what McLaren said.
McLaren never said 600kg at 150km/h and according to autoblog...it is definitely not the case, you have to be at more than 200km/h to have that.
At that speed a formula 1 car will produce 1100kg of downforce, double that of the P1 while weighting half less...4 times the level of aero grip.

Actually, you'd have more grip due to the increased downward force of aero downforce + weight combined, but also more centripetal acceleration required based on that grip.
Man that's non sense. Based on what you're trying to say a truck has more grip than a F1 car......

the P1 will have far less grip for cornering, accelerating and braking than an F1 car, i don't even understand how you can think otherwise while mclaren themselves say so..

Average speed of 160km/h implies average cornering speed significantly below that. And yes, power to drag is extremely important, which is why the movable aero will make such an important difference.
An average is an average, monaco has no significant straights and actually just have a look at formula1.com site you'll see half of the corners are taken between 150 and 250 km/h...

beelsebob
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Re: What if somebody built a faster lapping road car?

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Ogami musashi wrote:
Actually, you'd have more grip due to the increased downward force of aero downforce + weight combined, but also more centripetal acceleration required based on that grip.
Man that's non sense. Based on what you're trying to say a truck has more grip than a F1 car......
Uhhh... Yes a truck would have more grip than an F1 car, assuming it weighed more than about 3 tons, and had equally sticky tyres. Of course, it would also require more grip to make it go round a corner.

Ogami musashi
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Re: What if somebody built a faster lapping road car?

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beelsebob wrote:
Ogami musashi wrote:
Actually, you'd have more grip due to the increased downward force of aero downforce + weight combined, but also more centripetal acceleration required based on that grip.
Man that's non sense. Based on what you're trying to say a truck has more grip than a F1 car......
Uhhh... Yes a truck would have more grip than an F1 car, assuming it weighed more than about 3 tons, and had equally sticky tyres. Of course, it would also require more grip to make it go round a corner.
....

If you want to enter into details:

Tyres react to normal loading by increasing lateral force for a given slip angle; However rubber surface saturation decreases Lateral force/Normal load ratio which means for two times the normal load the car get less than 2 times the grip.
However the required lateral grip needed does increase linearly with weight hence more weight always means (except if you have grippier tyres...which is not the case for P1) less cornering speed.

And when you weight two times an F1 car, have two times less downforce/weight ratio...you can't beat it round corners (braking and accelerating out of them included)..be it monaco or anywhere else...

And again we are just speaking of downforce.

fiohaa
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Re: What if somebody built a faster lapping road car?

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Ogami musashi wrote:
However the required lateral grip needed does increase linearly with weight hence more weight always means (except if you have grippier tyres...which is not the case for P1) less cornering speed.
.
this is exactly right. Obviously if the vehicle weighs more, the tyre has to work harder to maintain the same level of lateral loads.

i think beelsebob is very confused.

although to be fair it is easy to get the concept of weight and downforce mixed up. actually im struggling now...i mean the extra 'weight' induced by downforce in an f1 car is slightly different to the standing weight of a truck...because its being physically pushed down by air.

So theres like a layer of heavy air compressing the car to the track.

This is not the same as a trucks weight bearing down on the tyres, theres nothing pushing the truck to the ground through the tyre. Its just a heavy truck....sat on some tyres. It would therefore have a huge amount of inertia going into a corner, and therefore a truck would NOT be able to corner at the same speed as an F1 car, even if it had max grippy tyres.

any physics majors here?

aussiegman
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Re: What if somebody built a faster lapping road car?

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markp wrote:Tyres? Roadcar has to last thousands of miles an F1 car about 100 miles per set. To produce the grip the road car tyres would have to be alot softer if they can do thousands of miles and generate same grip as F1 F1 would use them.
I would disagree with this assumption. I run road legal r-compound tyres that produce huge amounts of grip however would only last 250kms or less under normal use on public roads if I choose to do so.Look up Yokohama A050 soft / super soft compound, Hankook Ventus TD, Hoosier R6 etc. These are all DOT approved road legal tyres and so could be and in some cases are used as road tyres. The Toyo R888 and Yokohama A048 are examples of r-compound tyres provided on new road registered vehicles.

Another important point is that F1 tyres are not made for longevity, they are made to last through a very specific time envelope and dedicated performance window. Bridgestone tyres provided arguably more grip and better longevity, however F1 do not currently use them, which IMHO is a good thing, but thats another discussion. ;)
markp wrote:If they were softer they could not handle corner lads of F1 which has far harder tyres. If roadcar used F1 compounds the suspension would have to change makeing it undriveable on the road .
Not sure what you are getting at here to be honest. F1 doe snot have "harder" tyres, they have stiffer tyres with soft compounds. BIG difference. As above, you can run very soft compound tyres on road registered cars and it is still "drivable", albeit perhaps uncomfortable, but that ABSOLUTELY DOES NOT render it undrivable as you suggest.

An F1 tyre with a strong, stiff sidewall construction and soft compound will be more than able to handle cornering loads for a sports car. Again, look at the Yokoahama A050's used at the recent World Time Attack Challenge in Australia by the Evo of Team Nemo. This car ran A050 tyre's in a 295-30-18 soft compound and in turn 1 at Eastern Creek (Sydney Motorsport Park) and from the on board telemetry the Nemo Evo was pulling a lowly 260KPH on the front straight but was flat throttle at 260kph through turn 1 where it pulled 2.92G's, on road legal tyres.

Then there are road legal cars such as the Caparo T1which is road registerable, 470kg dry weight running a 575bhp @ 10,500 rpm V8 whihc gives it around 1000bhp per tonne and uses road tyres when it is actually working... ;)

So in short, could a road car be built to beat an F1 car?? Sure with enough money and effort most anything is possible, manned space flight is possible. However, it would have to obey the laws of physics and that's where it gets difficult. Its also important to decide how "flexible" you definition of "road car" is.

So IF (and its a big IF) you could build it, it would really cease to be any form or variant of a road car at all, it wouldn't be very drivable and would be full of compromises that would render it actually either a flawed road car or an average race car.

So is there currently any road car out there that could lap any of the F1 circuits quicker than an F1 car??

IMHO, no, not even close.

Furthermore, I don;t believe there is anything waiting in the wings either to even come close. Any road car will have huge compromises with regards to CoG, aero, tyres, brakes, suspension configuration (which have all been previously summed up by others) etc but most important would be its weight, weight distribution and CoG.
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xxChrisxx
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Re: What if somebody built a faster lapping road car?

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At a very broad stroke, you only need to compare four metrics to see which one will be faster.

Power to weight ratio. Acceleration.
Braking power to weight. Deceleration.
Downforce to weight ratio. (This broadly defines the traction circle - therefore your maximum cornering speed)
Drag to power. Max. Top speed.

The key to getting round a track in the shortest time possible is, to maintain the highest level of acceleration in the appropriate direction. Fortunately this works for any track scenario.

From that you have the workings of a very basic/crude lap simulator.


You can plug in the numbers yourself, but even if you are harsh on the Grand Prix car, and flatter the P12. You'll find that the racecar massively outstrips it in maximum possible lateral and longitudinal accelerations.

This is not to say a road legal car cannot be made to make F1 like numbers, the Caparo T1 is possibly the closest starting point.