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# Bugatti Chiron Super Sport 300+ specs

Car type | Coupe |

Curb weight | 1978 kg (4361 lbs) |

Introduced | 2020 |

Origin country | France |

Views | 6k |

Submitted by | lafars |

### Powertrain specs

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 |

### Chiron Super Sport 300+ competition

benedekpuskas 2m ago

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

nats50 9m ago

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

nats50 9m 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 9m 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 9m 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 9m 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?

manone 9m ago

it is not clear what your claim is. are you saying that these values that you provide

would equate to the top speed measured for the listed cars if plugged in the formula? It seems almost impossible to me that chiron 300 dropped cd from 0.36 to 0.32.

The problem is quantifying rolling resistance. a guy in https://drivetribe.com/p/technical-analysis-of-a-high-speed-P7t71_CaSSOMFdALcj_CWg?iid=SFD9PBiSSr25Dl5sTA_ayw

provided a reference to a "quartic polynomial model" for rolling coefficient, but did not provide computations. he came up with a drag coefficient of 0.27 necessary for Chiron to reach 490kph with 1600hp. I think it's plain impossible that Chiron 300 even comes close to having a cd of 0.27, if Chiron has 0.36 as stated.

SpeedKing 9m ago

The formula for the Koenigsegg top speed run suggesting that it only needs 1160 hp is unrealistic given that Koenigsegg claim that the Agera RS has 1360 hp which i believe it would need to achieve an average speed of 277 mph. In addition to that the 0% humidity that you've applied is impossible.

nats50 9m ago @manone

Hahaha, you guys haven't been paying attention. I didn't say that Bugatti actually admitting that they dropped Bugatti's Cd from 0.36 to 0.32. I'm only showing that the 1600 hp Chiron CAN ONLY achieve that 304.77 mph top speed

IF the Cd is down to that level! Or, the frontal area is reduced. Hello? Are you reading between the lines ? Otherwise, the car has to have more than the stated 1,600 hp. Either the frontal area or the Cd is reduced, or better both! I'm not forcing anyone to believe the formulas I'm displaying. You can use your formulas if that suits you.

nats50 9m ago @SpeedKing

Are you familiar with air density? I know 0% is almost unrealistic unless you live in the desert. But I didn't create or set STP--Stantard Temperature and Pressure to dry air or 0% humidity, or ISA and IUPAC. They are all set to standard 0% humidity. BUT OF COURSE, you can use different humidity level, temperature and pressure to reflect the real conditions and adjust the formulas and equations. Here, go to these VERY USEFUL AND INFORMATIVE website regarding air density or so-called density altitude, correction factors for dyno. . As I said to manone, I'm not forcing anyone to trust my formulas.

https://www.thoughtco.com/density-of-air-at-stp-607546

https://wahiduddin.net/calc/index.htm

nats50 9m ago @SpeedKing

BHP WHPa WHPr WHP Cr Pl S

1,360 bhp 1,287 whp + 30 whp = 1,317 bhp 0.012 Cr 3.2% 305 mph

1,360 bhp 1,225 whp + 29 whp = 1,254 bhp 0.011 Cr 7.8% 300 mph

1,360 bhp 1,164 whp + 28 whp = 1,192 bhp 0.011 Cr 12.4% 295 mph

BHP = Brake, crank or flywheel horsepower of the car

WHP = Total wheel horsepower needed to attain the top speed

WHPa = Wheel horsepower needed to overcome air resistance

WHPr = Wheel horsepower needed to overcome rolling resistance

Cr = Coefficient of rolling resistance

Pl = Power loss in percent = 1 - (WHP/BHP)

S = Top speed at these parameters

W = Weight of car and driver (assuming 165 lbs) = 3,078 + 165 = 3,243 lbs

Af = Frontal area = 20.16 sq ft

Cd = Coefficient of drag = 0.33

Pi = Tire pressure in psi = 44 (44 is usually used cause above 150 mph, tire pressure gains up to 7.5 psi because of heat. Some even 50 or more depending on the situation.

F = Factor such as 0.80 for 20% power loss, 0.83 for 17%, 0.85 for 15%, 0.90 for 10%, 0.95 for 5%, or whatever.

1 - (1,317/1,360) = 0.032 = 3.2%

1 - (1,254/1,360) = 0.078 = 7.8%

1 - (1,192/1,360) = 0.124 = 12.4%

Now, look at the results. For the car to attain 305 mph, the power loss must be at no more than about 3.2% which is kind of ridiculous or unrealistic. With 300 mph, the same car with the same parameters such as frontal area, drag coefficient, weight, etc., the power loss must be no more than about 7.8%, which is getting to be more realistic and achievable, right? Power loss below 10% or close to it is not that impossible or unheard of as some cars have achieved it. With 295 mph, you can probably bet your life on it that it is where some cars sit around, 8%-13%. Based on my formula or calculation, the car can achieve that speed with these parameters or specs. Finally, let me be very clear. The formula or equation assumes a standard rho of 1.225 kg/m^3 or 0.00237689 slug/ft^3, which is the standard air density at 59 F, 29.92 inHg and dry air or 0% humidity. Of course, in real life, the condition is not always there, specially humidity. That is why there is this dyno correction factor to correct the readings and results using the actual temperature, pressure and humidity or dew point, not to mention elevation. In other words, the true horsepower could be more or less than what is being used, therefore affecting the true top speed. Refer to my previous posts regarding the equations I'm using. And again, if you guys don't trust my formulas, it's not going to be my problem. Thanks for your time.

- Check these out, very useful information. Sorry for the lousy format. The browser or site doesn't support the correct or intended format.

https://wahiduddin.net/calc/cf.htm

http://www.mayfco.com/cdmodel.htm

manone 9m ago @nats50

"I'm only showing that the 1600 hp Chiron CAN ONLY achieve that 304.77 mph top speed

IF the Cd is down to that level! Or, the frontal area is reduced."

that is exactly what i asked. the frontal area is not decreased obivously, because the frontal projection of the car is the same (they just changed the rear of the car), thus they need 0.32cd, which i do not believe chiron 300 has.

But again, you may be underestimating rolling coeff. big time, as the guy in the link of my post gets a cd=0.27 for chiron 300 to hit 490kmh with 1600hp.

nats50 9m ago @manone

You see, his Cd of 0.27 is even much lower than 0.319 or 0.32 I'm using. As I have stated before, most people are too concentrated on the air resistance alone since it is widely believed that rolling resistance is really that insignificant or negligible, or that they don't have the formula or equation on hand. In fact, weight and speed affect it even if the rolling resistance amounts to only a few percent of the total resistance, but enough to screw the top speed result. 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.

manone 9m ago @SpeedKing

" In addition to that the 0% humidity that you've applied is impossible."

assuming 0% humidity, he is actually making the air denser (by the Avogardo Law) contrary to intuition, thus assuming an higher drag than there actually is. He should correct lowering the power figures he computes or increasing the speeds. Anyhow, i suspect he is hugely underestimating the tyres rolling

coefficient at speeds around 500kmh.

manone 9m ago @nats50

"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."

no it is definitely not quadratic in speed, as the graph in the link you posted days ago clearly shows. By the way, the expression you write is lacking a closing parenthesis.

Plus, there are no reliable models i know of for rolling res at 500kmh, simply because there are basically no tyres reaching that speed. i suspect the coeff blows up

SpeedKing 9m ago @nats50

Arguing about formulas is a lost cause and i prefer hands on real world experience. The number of variables required to accurately determine max speed, theoretically, is problematic, particularly for the Chiron SS because we don't have an accurate drag coefficient for starters. I'm very familiar with DA and grains of water in the air coz of my decades of drag racing experience. The bottom line is that most formulae are very useful tools but the same cannot be said of the formula for maximum speed accuracy.

Re hp loses from the crankshaft to the wheels that is constantly argued based on misinformation and ignorance. The most accurate measure of engine horsepower is achieved by using an engine dyno..fact. Drivetrain loss can be anywhere from 12% to 30% depending on what type of chassis dyno is used. Mustang dyno losses are the highest and Dynojet the lowest. Conversion factors are also a problem because many disagree on what % figure to use for each dyno based on the drivetrain configuration. It's NOT an exact art due to, once again, shitload of variables, so at best it's an approximation.

nats50 9m ago @manone

Yes, I did notice there was another parenthesis that I missed putting which makes an effect. I agree with you the equation the mechanical engineers probably wrote didn't expect cars would run 300 plus miles per hour. There are many rolling resistance equations that I've kept in my library, none of them agree with each other--some reading higher or lower than others even though the speed is the same. One equation would give a rolling resistance coefficient in the 80s, like 0.080, while others put it in the 20s like 0.020, while others are in between. You see, I've been experimenting different values that I think would truly reflect the speed given the power the car has. I have to admit the figures I wrote are now not entirely accurate due to the fact that I gave the rolling resistance coefficient too low probably because of the missing parenthesis that affected the equation. You see, as I said earlier, I use different equations from different sources regarding rolling resistance values. Another problem and cause of the wrong results is that the equation for rolling resistance coefficient was in the metric system, using meters per second for speed instead of miles per hour where I'm comfortable with, newtons instead of pounds, you get the idea. Now, I finally just converted the equation into the English system where it uses mph, lbs, psi and so on.

I'm sure you would agree with me that to determine the top speed of a car requires both the air resistance AND the rolling resistance. The air resistance determination is pretty much straightforward and not really problematic as the equation with rho is standard. It is the rolling resistance that has been the problem child. Also, regarding rho, it is true the value 1.225 or 0.00237689 or whatever system or value one uses is based on a "standard" temperature, pressure and humidity or dew point, at sea level. Yes, it was based on dry air or a humidity of 0 which is not realistic in the real world probably except useful only in the desert. I know how to determine the true value of rho under different environment using different temperature, pressure, humidity and even elevation included. Of course, the power of the car, and consequently, the top speed would vary--higher or lower than what I posted. But those calculations that I've been giving where obviously based on just standard conditions for demonstration purposes. I've saved dozens of sites on where to get values for air density, dyno correction factors which affects the performance of cars under different conditions. Here is another one that I use to determine rho using different temperature, pressure, and yes, not 0% humidity! https://www.brisbanehotairballooning.com.au/calculate-air-density/

Another one that you will definitely find very useful is this: https://wahiduddin.net/calc/cf.htm

I will try to post my final calculations later when I can. Since we use different equations and technique, I'm aware we would still have our discrepancies. No problem. And thanks for your time.

nats50 9m ago @SpeedKing

Hi there. Yes, I agree with you regarding the difficulty of determining top speed theoretically or just mathematically. As I said on my numerous previous posts, those power or drive train loss are only true based on the other figures and if they were met, not necessarily that they are the ACTUAL power loss. Yes, and I also said it on my numerous previous posts, the only accurate way of determining the horsepower of a car is by way of the DYNAMOMETER! However, as you are probably aware, there are different types of dynos, and each gives different results, not to mention the lack of experience or technical knowledge and even honesty some dyno centers have. As I just told manone regarding the calculation results, I did screw up a bit because of the rolling resistance coefficient that I used. You see, that equation, probably written by mechanical engineers, are in the Metric system of newtons, meters per second, kilograms and so on instead of the English system of pounds, miles per hour, pounds per square inch and so on that I'm working and more familiar with, and I had to convert each and every one of the parameters! On top of that, I missed that missing parenthesis on the rolling resistance equation that blew up the rolling resistance coefficient, hence lowering the wheel horsepower loss. My bad. However, that doesn't change the fact that to accurately calculate the theoretical or mathematical top speed of a car is BOTH air resistance or drag and rolling resistance are needed, not just the aero most people use. The other two, gradient and inertia, can be neglected since top speed runs are based on flat roads or tracks. The difficulty is really on the determination of the value of rolling resistance in the true world or not just empirical. The air resistance part is pretty much straightforward and well know. Not to mention that there are different types of top speed--rev limited, not to be confused with governor or electronically limited, gear limited, power or drag limited. You know that. Also, all the calculations that I presented obviously were based on standard temperature, pressure and humidity of 59 F or 15 C, 29.92 inHg or 1013.25 mb and dry air or zero humidity. Regarding humidity, of course, in real world situations, that is only possible in the deserts, but you get the idea. Not to mention also the value of rho that they were based on--the value of 1.225 or 0.00237689 or whatever value and system one uses. Using numerous websites that I go to just to determine the actual value of rho under different conditions, I know how to adjust. Regarding the drivetrain loss, I don't entirely agree with you on the numbers, the 12% to 30% values. Numerous experts and also based on the calculations I'm getting, it varies between near 10 to only as high as about near 20, not as high as 30. Well, I'm not going to debate with you on that. We're on our own.

Finally, as I said to manone, I will readjust the numbers again when I have the time. Actually, my earliest calculations were better because I sticked to the one rolling resistance coefficient equation I was comfortable with, but I just experimented with another one from another source. Oh well. Again, thanks for your time and I hope you don't take these conversations or posts personal for I don't. Cheers.

SpeedKing 9m ago @nats50

One can argue a position without getting personal. "I don't entirely agree with you on the numbers, the 12% to 30% values". Without going into intricate detail there are significant variations between inertia and load bearing chassis dynos which end up with different percentage losses through the drivetrain. On top of that FWD,RWD and AWD experience different powertrain losses so the 12-30% refers to all dyno types and vehicle drivetrain configurations.

PabloNescafebar 2d ago

Dude, you were almost spot on with the Tuatara, hit 331mph but 316mph with two run average. Although it ran that on E85 at 1,750hp.

nats50 9m ago

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

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

nats50 9m ago

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

HighGear 1y 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 1y 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 1y ago

very informative video regarding this car:

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

FastestLaps 1y 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.