The Fastest Car Isn't Always the Fastest Car

There’s an everlasting debate about racing’s relevance to road cars. Even the race cars that are based on road cars end up being quite different from one another. Both comply with very different rulebooks; both have very different use cases. But there is a lesson from racing that applies to road cars extremely well: The fastest car is not always the fastest car.

There are a lot of ways you can define "fastest car." For the purposes of this story, we’re going to talk in terms of lap time.

In racing, you have a lot of levers to pull to achieve a desired handling balance—springs, dampers, anti-roll bars, alignment, brake bias, and aero. Some race cars have a few more, some have a few less, but those are the basics. Race cars, like modern GT3 machines, also have traction control and ABS, and although they work differently from their road-car counterparts, the principles are the same.

You have a lot of those same levers in a road car, but add more advanced electronic systems like adaptive suspension, electronic locking differentials, stability control, etc. Slightly different set-up tools, but similar goals.

Making a car fast might just seem like a simple physics problem, then. But in reality, it’s an inexact science, thanks to the living, breathing human in the middle of the equation.

"The most ideal setup for speed is not always the best for drivers and drivability, and raceability," explains Adam Adelson, one of the drivers of the Wright Motorsport #120 Porsche 911 GT3 R in the IMSA WeatherTech series.

"You can have a car that’s super on the nose and theoretically capable of turning the fastest lap time, but if you have to be perfect to a tenth of a degree on your steering inputs, perfect to a millimeter on each pedal, you’re going to lose way more time in mistakes than you will have gained."

You can create a setup that might spit out an incredible lap time in a simulation, or one that a metronomically perfect driver could achieve in a time trial, but that isn’t the fastest in reality. There’s fast in theory, and fast in reality, and the two are quite different.

Good road-car engineers understand the same thing. Last year, Lamborghini CTO Rouven Mohr explained to Motor1 that in track testing, they’ll have drivers of different skills run times. “We compare the best time with the worst time [in a car], and this delta, this difference, should not be so big.”

Wright Motorsports - Petit Le Mans

Sports car racing is a team sport, so all the drivers have to agree on one setup that’s a reasonable compromise between what each other wants. You can make small tweaks to the setup throughout the race, but as Adelson’s teammate Elliott Skeer explains, you’re not changing springs on pit lane.

“If it’s a 40-minute single-driver race, it’s a lot easier to have an understanding of the conditions, the environments. [The team] can really suit a car to them,” he says. But, we’re speaking ahead of the 10-hour endurance at Petit Le Mans, which is not that.

“Over the course of 10 hours, three drivers, you’re going to see every sort of environment you can, it does become a game of averages,” Skeer explains, “where you are having to sacrifice certain corners for others, you are having to sacrifice certain hours of the day for others.”

Petit Le Mans starts under the mid-day Fall sun at 12:10 PM and ends in darkness at 10:10 PM that night. There’s a huge temperature drop when the sun goes in, so teams typically set up their car to be faster at night, at the expense of some performance during the day.

Skeer’s “game of averages” comment applies to road cars, too. Engineers have to optimize a car for a broad range of drivers, yes, making it as safe as possible while maintaining some speed, but also a broad range of conditions and environments.

Of course, while a high-performance road car may have electronic systems that can react to various external and driver inputs, it has to be set up to work on basically any road or track it’s on. A team like Wright Motorsports is obviously setting up the car for the specific track and conditions, looking in very granular detail.

In terms of handling, broadly speaking, the drivers want a car that goes where they point it, and that inspires confidence. You need enough front end that the car wants to turn, but a rear that follows dutifully. In a race environment, that’s super important as there’s always traffic to deal with. Even more so in multi-class racing like the IMSA WeatherTech series, where in a GT3 car, you’re a small fish in a big pond.

It’s the human element that makes this so interesting. There’s a lot of science involved, and as with all modern race teams, Wright Motorsport spends hours poring over data and video from the car. But they also have to match the data and video to the words drivers use to describe the car.

"We correlate what we’re saying, watching the video and matching that to our feedback," Adelson says, "That can be really important."

It’s this mix of soft and hard science that makes car setup so fascinating. Trying to put the subjective into objective terms, and also knowing the limits of what the objective tells you is correct. It’s an incredibly complex topic, but ultimately the goal is simple—make a car that can win the race.