Bridgestone Potenza 2019 review: S007A
December 11, 2018
Next time you shake someone’s hand consider the fact the contact patch you’ve just created approximates the amount of rubber connecting each corner of your car with the road.
Heading into a sweeping bend at 110km/h, that small round of applause is all that stands between a safe onward journey and becoming part of the scenery you’d been admiring only moments before.
For some, tyres are tedious. Replacing them is a pesky, grudge purchase. In fact, according to recent (IMRAS Consulting) research most of us rarely even look at the four round black things keeping our cars off the ground. Let alone consider their condition, inflation or performance.
Happily, while most of us don’t seem to give a rat’s about tyres, Bridgestone does, claiming to invest $800M in research and development every year, with 10,000 tyres tested on 200 different types of cars at 10 proving ground in eight countries.
And for an ultra-engaged group of performance-focused drivers, tyres are rightly regarded as crucially important. Not just in terms of safety, but a host of attributes including grip, response, stability, wear and comfort.
Enter Bridgestone’s Potenza S007A, the Japanese tyre giant’s new high-performance flagship, sitting above the already well-credentialled Potenza S001, and creeping up on the semi-slick, Potenza RE070 track day warrior.
This is a top-shelf, Y-rated option offered from 17-inch up to monster (305/30) 20-inch fitment. Think replacement rubber for Mercedes-AMGs, Porsche 911s, Aston-Martins, Lexus F, and BMW M (which we’ll get to in a minute).
The balancing act in designing and developing a high-performance tyre is fundamentally between the ability to key in and conform to the road surface at a microscopic level, yet remain firm and squirm-free overall.
So, while the S007A uses Bridgestone’s high-grip ‘Nano Pro-Tech’ compound it also features a Kevlar flipper (the strip that connects the main part of the tyre into the sidewall) to increase rigidity, and hybrid spiral cap (an additional layer running shoulder-to-shoulder around the circumference of the tyre).
The result is a 2.5sec advantage over the S001 around a roughly 90sec track lap. But making a faster tyre is one thing. Making it civilised and able to last more than a single qualifying session is another.
We were invited to sample the new top-end rubber at the sweeping Phillip Island race circuit, in a modified version of BMW’s ‘Driving Experience’ course with a host of fast and furious ‘M’ cars on hand, as well as a team of tame racing drivers to guide proceedings.
The program ran through exercises including a ‘brake, swerve and recover’ drill, a slalom run, a wet skidpan drift session, as well as hot laps around PI’s undulating 4.5km layout.
Pounding the powerhouse (272kW/465Nm) M2 down the start/finish straight towards the daunting turn one, the car feels reassuringly stable under heavy braking, and beautifully responsive on the sweep out to the Southern Loop.
The tight and technical double apex left-hander rewards patience and while the S007As grip hard, it’s immediately clear there’s something missing.
I’d noticed it (or not) from pit lane as fellow participants blasted around the track. Plenty of engine noise and wind roar, but not a peep out of the rubber. No tyre squeal, at all.
Sure, you’ve got a tricky diff and a host of electronic gee-whizzery on your side as well, but dialling up extra power and speed in the (317kW/550Nm) M4, the picture remained unchanged. Rock solid stability, mega grip and predictable response.
One of the most telling comparisons was the brake and swerve exercise where we were able to back-to-back the S007A with the S001. Same car, same time, same conditions.
And this is where the S007A’s rounded, or chamfered, tread blocks came to the fore. According to Bridgestone they allow higher contact pressure and prevent deformation of the tyre under load.
Driving at a steady 80km/h towards a light you know is going to flash red an instant before you reach a tightly grouped maze of safety cones is unnerving. Mainly because as it lights up the challenge is to hit maximum braking, at the same time swerving left and bringing the car to a straight, high-pressure halt, without ‘rearranging’ a single cone.
The S007A features an extra-stiff central rib (there are three ribs in total) designed to improve stability and response. And then there are the sipes (thin grooves in the shoulder and across the face of the tyre).
Low angled sipes on the inner tread are there to provide extra control in cornering, and ‘three-dimensional M-shaped’ sipes on the outer treads are claimed to prevent unnecessary movement and prolong tyre life.
Obviously, a track test day like this doesn’t exactly shine a light on durability, but BMW Driving Experience manager, Doug Greenslade says following the program’s shift to the S007A he’s seen average tyre life nearly double.
Also tough to assess ride comfort, given the Phillip Island surface is like a big, black billiard table. But, while consciously aiming to block the power of suggestion, it felt like the S007A had a discernible edge over the S001 in terms of stability, braking performance and cornering response.
The slalom run backed up that impression, and the wet skidpan exercise was just a lot of fun, with the tyres doing their best to disperse water from a variable surface and sit at the edge of adhesion for as long as possible.
The (recommended retail) price you’ll pay to put these high-tech hoops under your ride ranges from $290 to $620 a corner. A BMW M3/M4 for example, will set you back $495 for each front and $569 for each rear to accommodate the staggered fitment.
And all we can say after pushing it to the limit (and beyond) is for that money the Potenza S007A delivers a confidence-inspiring combination of grip, stability and dynamic response.