Quote>"The Tuatara also has a more slippery shape, with a smaller frontal area than the Chiron (1.672m2 vs *2.072m2* ) and a lower drag coefficient (0.279 vs *0.319* ).

I HAVEN'T seen those numbers before!

:O

Car type | Coupe |

Curb weight | 1978 kg (4361 lbs) |

Introduced | 2020 |

Origin country | France |

Views | 7.9k |

Submitted by | lafars |

Engine type | quad-turbo W16 |

Displacement | 8.0 l (488 ci) |

Power | 1622 ps (1600 bhp / 1193 kw) @ 7000 rpm |

Power / liter | 203 ps (200 hp) |

Power / weight | 820 ps (809 bhp) / t |

Transmission | 7-speed DCT |

Layout | middle engine, all wheel drive |

ChironSS 3w ago

Quote>"The Tuatara also has a more slippery shape, with a smaller frontal area than the Chiron (1.672m2 vs *2.072m2* ) and a lower drag coefficient (0.279 vs *0.319* ).

I HAVEN'T seen those numbers before!

:O

ChironSS 3w ago

https://www.autoblog.com/2019/09/19/bugatti-chiron-andy-wallace-interview-speed-record/

Quote>""I don't think that's the v-max of the car, because it was still accelerating. At that speed, **you cover a kilometer about every seven seconds** . Then, of course, at the other end you need some distance — not necessarily time, but quite a lot of distance — to get the car down to the right speed for the banking," Wallace remembered.

He added that, in hindsight, he might have been able to keep his foot on the throttle for about one more second before hitting the brakes. That wouldn't have been enough to cross the symbolic 500-kilometers-per-hour (310-mph) threshold, but it would have added about **another mile per hour to his record** . "We need less drag or a longer road to go faster," he explained.

That top speed statistic is incredible! Also I wish he'd stayed on the hammer for another second! :)

ChironSS 1m ago

So a recap thus far and what do we know>

*claimed 0-100km/h= 2.4 seconds

300-400km/h= 10 seconds (although I've clocked it at 9 seconds)

490.484km/h verified speed at Ehra-Lessien although this is not peak velocity.

515km/h peak velocity as per Stefan Ellrott calculations.

Ability to keep up within circa 2mph of the SSC Tuatara in it's first to it's peak velocity. And ability to be within 4mph of the Tuataras second run until circa 270MPH which is where it's limiter kicks in anyway for the production cars.

I've got to say LOVE the SSC (Castriota knocked it right the hell out of the park aesthetically- undeniably) but the Bugatti thus far has is holding it's ground.

:)

ChironSS 2m ago

https://www.carsales.com.au/editorial/details/bugatti-chiron-super-sport-300-almost-sold-out-120580/

Quote>"Wallace said **accelerating from 250 to 490km/h** during the record run took **just 57 seconds**, which is a staggering statistic in itself."

So a confirmed time by Andy Wallace. If you've seen him in interviews he's got a VERY sharp memory for facts and figures and this is the FIRST statisctic relating to acceleration I've ever seen anyone from Bugatti make regards the Chiron Supersport.

Now luckily for us the ex World Record 0-400-0km/h records are available in the 0-300km/h. 250km/h sits exactly in the middle obviously of 200km/h and 300km/h. These VERIFIED values are 6.1 and 13.1 respectively. So the average to calculate 250km/h 9.6 seconds.

So 57+9.6= 66.6 seconds (666 hahaha)

Therefore 0-490km/h takes 66.6 seconds. That's actually a JUICY little metric there. And in of itself it's actually quick for the Bugatti Chiron.

I'll calculate a 0-490-0km/h at somepoint too.

Yeah it'll possibly get beaten by SSC or Hennessey, but know what I REALLY don't care. Bugatti is Bugatti. :)

ChironSS 2m ago

These are mathematical calculations for the Bugatti Chiron Supersport 300+ production car based on official current Bugatti sources and resources of which were multifold. And these are published ahead of it's production release for verification and authentication purposes. It's going to be an absolute MONSTER! Just some lockdown mental activity! Vive la Marque!

0-100km/h= 2.3 seconds

0-200km/h= 5.5 seconds

0-300km/h= 11.6 seconds

0-400km/h= 22.29 seconds

0-500km/h= 63.71 seconds

0-100-0km/h= 4.83 seconds

0-200-0km/h= 10.18 seconds

0-300-0km/h= 18.27 seconds

0-400-0km/h= 31.65 seconds

0-500-0km/h= 75.41 seconds

100-0km/h= 2.53 seconds

200-0km/h= 4.68 seconds

300-0km/h= 6.67 seconds

400-0km/h= 9.36 seconds

500-0km/h= 11.70 seconds

100-200km/h= 3.2 seconds

200-300km/h= 6.1 seconds

300-400km/h= 10.69 seconds

400-500km/h= 41.42 seconds

Top Speed= 515km/h Bugatti *claimed top speed

1/4 mile= 9.1 seconds @164MPH (E)

:)

SpeedKing 6m ago

It appears Bugatti has resorted to witchcraft...WTF!!

https://www.topgear.com/car-news/concept/bugatti-bolide-mind-blowing-1824bhp-track-car

benedekpuskas 8m ago

"Visit carwow.co.uk to see how much you can save on a Bugatti Chiron 300+"

nats50 1y ago

Here is another site on how to calculate air density or rho under different temperature, pressure and humidity or dew point.

nats50 1y ago

Here is another site on how to calculate air density or rho under different temperature, pressure and humidity or dew point. https://www.brisbanehotairballooning.com.au/calculate-air-density/

nats50 1y ago

And here is a very useful site in getting the air density or density altitude, dyno correction factor, etc... Enjoy! https://wahiduddin.net/calc/index.htm

nats50 1y ago

Here is the formula I now use for determining the coefficient of rolling resistance. The SAE suggested an empirical formula for the rolling resistance in dependence of inflation pressure pi [N/m^2], forward velocity v [m/s] and tire load Fz [N]:

Fr = K/1000(5.1 + 5.5 x 10^5 + 90 Fz/pi + 1100 + 0.0388Fz/pi)v^2 where the factor K is taken as 0.8 for radial tires and as 1 for non-radial tires.

Fr = Rolling resistance

Fz = Tire load in N = newtons

pi = Inflation or tire pressure in N/m^2

v = Velocity or speed in m/s

Cr = Coefficient of rolling resistance (unitless)

m = Mass in kilograms

g = Acceleration due to gravity = 9.80665

Hw = Wheel Horsepower

Af = Frontal area in sq ft

Cd = Coefficient of drag

S = Speed in mph

W = Weight of car and driver in pounds

Fr = Crmg

Hw = 0.0025565AfCdS^3/375 + CrSW/375 -> divide the result by a factor such as 0.80 for 20% power loss, 0.83 for 17%, 0.85 for 15%, 0.87 for 13%, and so on to get the crank or flywheel horsepower needed to attain the top speed. Convert the units as needed.

nats50 1y ago

I've done this revised calculations on the top speed using my own version, with a twist, of known formulas and equations . It can be achieved if it meets these parameters. Of course, there are many possible combinations of frontal area and drag coefficient, not to mention power loss which can only be accurately determined by putting the car on a dyno. There are many formulas or equations on predicting accurately the theoretical top speed--from the simplest to the most complex. As you probably know, there are like 4 forces or resistance acting on a moving car that influence top speed--air resistance; rolling resistance; gradient resistance and inertia. The first two are the most prominent. The gradient is usually not included in the mix cause top speed is supposed to be run on a relatively flat road or track, and that is why two runs, from both directions, are needed to negate any possible slope, uphill and downhill, not to mention wind, and just average the two speeds. Inertia is also neglected or may be insignificant for some reason. Anyway, I've developed my own version and I came up with these results. As I said earlier, there are infinite number of combinations you can do to arrive at the same top speed theoretically. Before I forget, they are based on standard temperature, pressure and humidity of--59 F, 29.92 inHg and 0% humidity--rho at 1.225 kg/m^3 or 0.00237689 slug/ft^3. They all mean the same thing. There are formulas out there on how to determine rho exactly using different temperature, pressure or elevation, and humidity. That is why I use or the constant 0.0025565 is used to simplify. Also, it must be known that there are different types of top speed--gear limited and rev limited (not to be confused with governor or electronically), power or drag limited. Finally, the frequently neglected and "insignificant" rolling resistance seems to be the more problematic one. There are many formulas or equations on how to determine the rolling resistance value. It can be seen that tire pressure, weight and even speed affect rolling resistance and consequently top speed. The air resistance is pretty much straightforward and well known. Again, I came up with these results and here they are:

Hc = Crank or flywheel horsepower

Hw = Wheel horsepower

Af = Frontal area in square feet

Cd = Drag coefficient

Pl = Power loss in percent

Pi = Tire pressure in psi (44 is usually used)

Cr = Coefficient of rolling resistance

W = Curb weight of car plus driver (165 is normally used) in pounds

S = Speed in miles per hour

Bugatti Chiron Super Sport 300+

Hc = 1,600 bhp -> 1622ps

Hw = 1,373 whp (air resistance) + 35 whp (rolling resistance) = 1,408 whp

Af = 22.30 sq ft -> 2.072 sq m

Cd = 0.319

Pl = 12.0%

Pi = 44 psi

Cr = 0.0095

W = 4,526 (4,361 + 165) lbs

S = 304.77 mph

Koenigsegg Agera RS

Hc = 1,144 bhp -> 1,160ps

Hw = 973 whp (air resistance) + 23 whp (rolling resistance) = 996 whp

Af = 20.16 sq ft -> 1.873 sq m

Cd = 0.330

Pl = 12.9%

Pi = 44 psi

Cr = 0.0096

W = 3,243 (3,078 + 165) lbs

S = 277.87 mph

SSC Tuatara

Hc = 1,350 bhp -> 1,369 ps

Hw = 1,030 whp (air resistance) + 31 whp (rolling resistance) = 1,061 whp -> 21.4% power loss -> 0.013 -> 311.00 mph

Hw = 1,070 whp (air resistance) + 32 whp (rolling resistance) = 1,102 whp -> 18.4% power loss -> 0.013 -> 315.00 mph

Hw = 1,122 whp (air resistance) + 40 whp (rolling resistance) = 1,162 whp -> 13.9% power loss -> 0.014 -> 320.00 mph

Af = 18.00 sq ft -> 1.672 sq m

Cd = 0.279

Pl = 21.4%, 18.4%, 13.9%

Pi = 44 psi

Cr = 0.013, 0.013, 0.014

W = 2,915 (2,750 + 165) lbs

S = 311.00 mph, 315.00 mph, 320 mph -> calculated top speed?

nats50 1y ago

https://www.facebook.com/watch/?t=10&v=191073695633737

A simple case of power to weight ratio win by Koenigsegg?

nats50 1y ago

Want to know the approximate wheel horsepower loss at altitude? http://dgm2780.austinbroadhead.com/whpCalculator/

HighGear 2y ago

Source: https://www.topgear.com/car-news/supercars/bugatti-chiron-super-sport-300-production-300mph-car

The power output is 1,578 hp (1,600 PS).

Price: 4.2 Million pounds (5.18 Million US dollars)

Top Speed: 304.77mph*

*https://www.topgear.com/car-news/bugatti-has-broken-300mph-barrier?fpn=1

manone 2y ago

"Why can't it reach 490 kph with 1600 ps? What are those "engineering peeps" that are so convinced it can't? Have they studied the shape of the car?"

Ok, let's do few computations for Veyron SS. The formula relating power to CdA, speed v and air density rho is:

P = CdA * v^3 * rho/2.

Knowing V=431km/h=119.7 m/s, P=1200bhp=895kw and rho@15C=1.225 kg/m^3,

we get a CdA of 0.85.

Therefore, for the Veyron SS to reach 490km/h you need 1307kw=1753bhp for

overcoming the drag alone from 431kmh to 490kmh. Then you have to add:

Back to the Chiron SS: the A factor of Cd*A is seemingly not less than the

Veyron SS's. How much they could have decreased the Cd from the Veyron SS to the Chiron SS, provided the extra front venting surfaces the latter has?

lafars 2y ago

very informative video regarding this car:

https://www.youtube.com/watch?v=DFlUYWfwOUg

FastestLaps 2y ago

You know what is the saddest part - we still don't have proper data for the original Chiron :D

Bugatti are basically pulling a Christian von Koenigsegg.