tyre test - goodyear eagle f1 asymmetric 2
power to the people
Choosing the right tyre for your high performance car can make an enormous difference. But which tyre? Andy Enright checks out Goodyear's Eagle F1 Asymmetric 2
As any automotive engineer knows, the biggest gains in performance for any sporting car are to be found not beneath the bonnet, but beneath the wheels. Yet choosing the right rubber for any powerful car can be a bewildering process. Goodyear's latest Eagle F1 Asymmetric 2 tyre claims to simplify the process a good deal.
To appreciate the kind of difference that such a tyre can make, let's assume you've a dream two-car garage. On one side, sits a classic Lamborghini Miura, by any standards an awesome supercar. With a massive 285bhp/tonne power to weight ratio, this Italian would manage to hit 100mph from a standstill in 15.6 seconds. On the other side of this mythical garage, let's assume you've something still exciting but a little more accessible - say a Porsche Cayman S. The Stuttgart coupe would be good for a mere 237bhp/tonne, yet fit a data logger to this car and you'll find that even with the traction control switched off, it would take comfortably less than 12 seconds to breach 100mph.
Yes, there have been advances in engine tractability and the Porsche is a little slipperier through the air than the venerable Lambo, but the lion's share of that yawning gulf between the two cars comes down to tyres. Whereas the Lamborghini's torque would rapidly overwhelm its Pirelli Cinturatos, requiring power to be fed carefully, the Goodyear Eagle F1 Asymmetric 2 tyres fitted to the Porsche just grip and go.
That two mid-engined, rear wheel drive cars can produce such massively different acceleration figures will surprise many but tyre technology never stands still and, at the time of writing, the Eagle F1 Asymmetric 2 stands as an exemplar of the state of the art. Naturally, grip off the line is but a small part of a tyre's dynamic repertoire and Goodyear has incorporated what it dubs ActiveBraking Technology into this tyre. Your car sits on four tyre contact patches, each about the size of your hand. The Eagle F1 Asymmetric 2 features tread blocks that increase in surface area under heavy braking, bringing more rubber into contact with the road. A high silica content in the rubber also improves grip in both wet and dry.
Enthusiast drivers may read the aforementioned paragraph and think that it's a recipe for 'tread shuffle', the unwelcome feeling when a tyre laterally squirms on its tread blocks through corners, but Goodyear has engineered a huge degree of lateral stiffness into the tyre. The crossed ply carcass also means that the sidewalls are also beefy, helping improve steering response and on-limit handling.
The Eagle F1 Asymmetric 2 was also put through the wringer by independent testing organisation T£V S£D Automotive at test tracks in France and Germany. The tyre performed extremely well, delivering a three metre shorter braking distance on wet roads compared to the average performance of three leading competitors it was tested against. The tyre also performed well in dry braking and handling tests, stopping 2 metres shorter than the average performance of the three leading competitors. On dry roads, the competitors tested were still travelling at an average speed of 24km/h while the Goodyear had already come to a stop. That could easily be the difference between a sweaty brow and a big insurance claim.
Go, stop and steer in both wet and dry would seem to be the main elements of a tyre's make-up but consumers these days demand more. Low noise levels, low rolling resistance and long life are also required and some of these elements at first seem to be in direct opposition to a tyre that offers fierce grip. By reducing the weight of the tyre, Goodyear has reduced heat build up, the carcass of the tyre effectively acting as a heat sink for the rubber. This is helped by the silica compound, which also helps dissipate heat. A cool tyre is one that rolls more efficiently. There was even a team assigned to making the sidewalls more aerodynamic to help reduce energy losses at high speed.
Nobody wants a tyre that feels great for a couple of thousand miles but then falls off a cliff in terms of performance as soon as it begins to wear. The Eagle F1 Asymmetric 2 tread stiffness across the contact patch results in a uniform pressure, which in turn means a longer lasting tyre. A great deal of effort was also directed at reducing the noise level of the tyre and Goodyear has developed what it calls a 4 Pitches Sequence with 64 blocks on the outside of the tyre and 72 blocks on the inside which break up harmonic noise and offers an agreeably quiet ride at speed.
The sheer pace of tyre development can be dizzying and it's often tempting to pick a brand and stick with it, but the variability even amongst the premium tyre brands is often worryingly large. The T£V S£D Automotive tests weren't putting the Goodyear up against shoddy Chinese 'ditchfinder' tyres. Instead it benchmarked comparative rubber from Bridgestone, Continental and Pirelli and the Eagle F1 Asymmetric 2 excelled in all braking and handling disciplines while also offering the lowest rolling resistance on test, which would seem to be just rubbing salt into its rivals' wounds. Let's just celebrate the fact that choosing a road tyre for your performance car just got a whole lot easier.