First, using my own formulas and method then compared it to the standard method and formulas. These calculators are heaven sent. Before, solving equations manually are tedious and cumbersome. Instead of several minutes to solve a top speed equation, it only takes several seconds or less than half a minute using these calculators! Whew. It is just the inputting of constants and variables that takes time.

2021 Koenigsegg Jesko Absolut

Hc = (0.00000556517pAfCdS^3+ 0.0026667CrSWt)/Pf

Pf = 5,252Hc/EpTp

Where:

Hc = Horsepower 1,602 (1,624 PS)

EP = 7,800 rpm

Tp = 1,106 lb-ft @5,100 rpm

p = 1.204 kg/m^3

Af = 20.24 sq ft

Cd = 0.278

S = 324.77 mph @42.5 psi

Wt = 3,064 (car); 165 (driver) = 3,229 lbs

Pf = 0.97530

Cr = 0.0969

Using the standard power equation Pn = [0.5pCdAV^2+ Cr(M+Df)g]V, with 0.90 drivetrain efficiency and 0.015 rolling coefficient, the top speed translates to 333.55 mph.

1,602*745.7*0.90 = (0.5*1.204*0.278*1.88)V^3 + (0.015*1,464*9.8067)V

1,075,150 = 0.314629V^3 + 215.355V

0.314629V^3 + 215.355V - 1,075,150 = 45 or almost zero.

Solving the polynomial, velocity turned out to be 149.11 meters per second, 333.55 mph, or 536.68 kph — assuming the specs and parameters are those used. Higher than 0.90 drivetrain efficiency such as 0.91 or 0.95 whatever will result to higher top speed than this and vice versa. Also, lower than 0.015 such as 0.014 or 0.010 whatever will also result to higher top speed and vice versa. Not to be ignored is the actual air density, maybe added downforce, etc. — they all needed to be considered. We'll see when Koenigsegg actually does the top speed run.