Racing has long paved the way for a plethora of performance and safety innovations for road cars. Think anti-lock brakes, carbon fiber, paddle shifters and rear-view mirrors, just to name a few. The racetrack is often a test bench to experiment with these features before they are homologated into road vehicles.
That trickle continues in the latest high-performance Firehawk AS V2 racing tire, which benefits from blazing fast IndyCar technology. (Firestone has been the exclusive tire supplier for IndyCar racing since Ray Harroun’s victory in the opening race of the Indy 500.) This wet tire is particularly important because Firestone claims it is 2.1 seconds faster than version one (on a lap around a wet race track). If that’s true, that’s a big, impressive leap – more than we usually see between generations of ties. We spoke to the Firestone technical team to see how they were doing and what it could mean for your riding if you released a set.
Simulate tread patterns
The NTT IndyCar series features the fastest open-wheel race cars in the United States. Firestone had to design a rain tire that could compete with the vicious power and downforce of a purebred IndyCar machine. That’s great, but you might be wondering how that wet-weather performance benefits mere mortals like you and me as we ride down the street.
Firestone’s racing division used Computational Fluid Dynamics (CFD) software to analyze and perfect the interaction of the tread pattern with a layer of water on the road. “Many tire manufacturers talk about the water flowing through the tread, but it almost knocks the water out of the way,” said Dale Harrigle, chief engineer of consumer tires at Firestone. These CFD simulations allowed the engineers to play around with different tread patterns to find the best performer before spending money on prototyping.
Engineering versus compromise
So we know that these tires are inspired by the IndyCar rain tire. While the Indycar tire can only be tuned for absolute performance, road tires present a very different set of challenges. Road use rubber should perform well and last up to 50,000 miles, in dry, wet, hot and cold conditions. “You will have people who drive very extreme on their tires, and you will also have others who treat every day like a Sunday ride,” said Ian McKenney, Firestone’s senior product manager for consumer replacement tires. The goal here is to cater to the needs of each customer. But how does Firestone find and achieve this balance?
“The tread compound that works in tandem with the tread pattern provides the performance improvement we’ve seen over the previous tire,” says Harrigle. The latest Firehawk racing tire has high amounts of silica in the tread compound to increase traction in wet conditions; compared to the original Firehawk AS, the V2 shaved 2.1 seconds off the wet lap evaluation on the track and helped the test vehicle stop 1.5 meters shorter in the snow – all while maintaining the most dry performance and wear of the tread remained reasonable.
That’s well and good, but tire engineers are constantly faced with trade-offs when designing new rubber. “There are fundamental design goals that have yet to be solved with current technology,” said Jonathan Benson, an independent tire testing expert and founder of Tire Reviews-adding that tread/compound changes generally yield very incremental improvements over massive breakthroughs. Despite Firestone’s mention that it outperformed General Tire and BFGoodrich in snow braking and wet lap times, it still seems to be outclassed by bigger brands such as Michelin and Pirelli.
Why this is a big problem?
Benson had more to say about this Ultra-high performance all season tire category: “It’s a type of tire that doesn’t work super well because you’re trying to mix too many things. Snow and high performance are opposing design goals in terms of rubber compound and construction. Rubber can only be really good at one job. For example, if you incorporate winter performance into a tire intended for track use, the performance will be reduced on dry and wet surfaces.
He was also quick to say that this Ultra-High Performance All-Season category doesn’t really exist outside of America. “I think a lot of people in the industry are also trying to focus the name of these tires on three-season tires,” says Benson. They really aren’t designed to work well in heavy snow or ice. Tire manufacturers in this category have to choose a delicate balance between dry, wet and winter properties.
Summer tires will always reign supreme when it comes to absolute performance. However, these are only usable in, well, summer conditions; of Popular mechanics Since we are stationed in eastern Pennsylvania, we only get a handful of usable months on summer rubber. All-season or even extreme winter tires are the norm for us East Coasters.
The improved track performance of Firestone’s latest Firehawk is only superficial. An added benefit is that they can keep you safe in cold and wet conditions, all thanks to better traction and shorter braking distances. That said, if the snow starts to fall, we would probably still be looking for a dedicated winter tire.
Matt Crisara is an Austinite born with an unbridled passion for cars and motorsport, both overseas and domestic, and as Autos Editor for Popular mechanics, he writes most of the automotive reporting on digital and print. He was previously a contributing writer for Motor1 after internships with Circuit Of The Americas F1 Track and Speed City, an Austin radio broadcaster focused on the world of auto racing. He received a bachelor’s degree from the University of Arizona School of Journalism, where he raced mountain bikes with the University Club Team. When not at work, he enjoys sim racing, FPV drones and the outdoors.