A quick look at the drag of Hypercars.

An adjustment for High Speed Power was introduced into FIA WEC in 2024 and IMSA for 2025. After reviewing the BoP adjustments for High Speed Power it seems that the FIA adjust the power in a linear fashion to correct for this.

It appears they are using a formula similar to:

1% change to High Speed Power results in 0.73% change in Top Speed

Intuitively this is reasonable as at high speed drag is proportional to the to the velocity squared. Or 1% increase in power would offset drag force from increase of 0.5%.

We can have a quick and dirty look at the base Top Speed rankings of the cars. i.e. the Top Speed with the same power.

• This assumes 0.73% impact to top speed trap data for 1% change in high speed power (for Qatar BoP it was measured as 0.72% and 0.74% for Imola).
• It assumes Speed Trap is Top Speed. Which is probably OK.
• It has used the fastest example of each car from each race.
  • We have seen set-up differences between teams with the same car and even between cars of the same team.
• It is expressed as a % variation of the mean of this population.

Takeaways

• The Cadillac and Toyota, look and are bulky cars.
• Other than Toyota, the Hypercars generally perform well here. Especially the slippery French cars.
• Aston looks middle of the pack, but it is early BoP days for it. This could change…

Background:

Qatar (Prologue) adjustment in High Speed Power BoP v. average Speed Trap data for (COTA, Fuji, and Bahrain)¹.

Imola adjustment in High Speed Power BoP v. average Speed Trap data for (Fuji, Bahrain, and Qatar)².

1. Understanding the New Balance of Performance Approach, Equipe43, 3/13/2024. ↩︎
2. Imola BoP, Equipe43, 4/11/2024 ↩︎