So, you may be thinking of him finally hitting 200mph at El Mirage. He went 208, but that is only 1.5 miles. The car has gone 261mph. HP is cubed as speed increases.
Example: The power is proportional to the speed. To find the power take the ratio of the two speeds and cube that number. (power needed to go 180mph if 500hp gets you to 160mph) 180/160 = 1.125, 1.125 cubed =1.438 so 500 hp x 1.438 = 712 hp, rounded up So it takes 212hp just to increase speed by 20mph
DRAG goes up as Square of velocity. HORSEPOWER goes up as CUBE.
So my 200mph needs much less power than his 260mph. 260/200 = 1.3. 1.3 cubed is 2.197. so 1200hp (Freighburger's HP) divided by 2.197 = 546hp needed if all things equal. Obviously more is needed as the cars are very different, traction needs etc...