Bespoke tyres are big business these days. Off-the-shelf tyres might be better than ever, but as cars get faster and more capable, manufacturers are wanting more control over how the hoops fitted to their cars behave.
Exactly what is tweaked varies from project to project, but in the case of the Michelin Pilot Sport 4S used on the new BMW G80 M3 and G82 M4, the changes are significant and wide-ranging. As Jon Benson explains in the latest Tyre Reviews video, changes to the star-marked OE 4S include the use of four compounds rather than two (comparable to a Pilot Sport Cup 2), a tighter belt in the middle for a better contact patch, altered sidewall rigidity plus tweaked groove widths and depths.
Michelin spent two and a half years developing these for BMW, testing 30 different iterations of the 4S for each axle at five different circuits. The level of detail that’s gone into the development, as Benson excitedly explains in this fantastic geek-fest of a tyre video, is ridiculous.
So how does that translate into what your feel behind the wheel? To find out, Benson drove an M3 at one of Michelin’s facilities in France for a series of tests. First, the car was shod in aftermarket 4S hoops, then in the OE versions. We’ll let the man take you through the differences in the way the car feels and behaves, but suffice to say, they’re significant.
Once it’s replacement time, then (which might happen sooner rather than later if you’re playing about with the M3/M4’s Drift Analyser), it’s worth paying the extra to go OE. The caveat is this advice might change a little down the road. As noted in a previous Tyre Reviews video, owners of BMWs that have the star-marked Pilot Super Sport as the recommended tyre now have the option of buying a newer off-the-shelf 4S and getting better performance in return.
If you’re buying a used performance car from the last few years, it’s worth your while checking if the owner has fitted the recommended bespoke tyre. Thankfully, they’re easily given away by markings on the sidewall noted in this video’s description. Examples include BMW’s star, VW’s ‘+’, ‘AM’ for Aston Martin and NR1 for Nissan. A set of the right boots is the sign of a conscientious owner, but failing that, just make sure they’ve fitted a good set of tyres and not a set of rubbish budgets. Or worse yet, a mix of the two.