You can’t help but feel that not enough importance is placed on tyres. It’s your car’s only point of contact with the road, so few components can affect the way your ride feels quite so dramatically as these rubber hoops.
That’s certainly what we found after switching ‘our’ old Honda Civic Type R longtermer to Michelin Pilot Sport Cup 2 tyres last year, but the trouble with the Cup 2s is they’re a very extreme, dry-biased tyre. The better compromise would be the French tyre maker’s Super Sport range, and it just so happens a replacement is now available: Pilot Sport 4S, or PS 4 S for short.
It’s not - as the name might imply - a four-season tyre. It’s all part of Michelin’s efforts to tidy up its naming structure, bringing these sportier boots in line with the ‘standard’ Pilot Sport range. But what are they like? Let’s take a look at the construction of the tyres, then get to the testing.
Outside of the world of motorsport, tyres have to do more than one job. They need to be grippy in both the wet and the dry, which means some sort of compromise is needed. The PS 4 S gets around this to some extent, by offering a dual compound, something that’s only been possible to construct quite recently.
It uses a “new hybrid compound” on the outer part of the tyre for dry grip, with a compound geared toward offering consistent wet grip on the inner part made from “silica and functional elastomers” (below left). The tread pattern is asymmetric too, with the outer portion given a pattern more suited for the dry, and the inner part is - as you probably gathered - geared more toward the wet.
Next up, we have the belt to consider. It’s nothing so simple and vulgar as steel: no, instead the PS 4 S gets a belt made from a blend of aramid fibre and nylon (above right), which means the tyre is better at keeping its shape during high-stress situations. As a result, the contact patch won’t reduce in size quite so much when you’re throwing your car around, and the steering should be more reactive too, with unwanted flex reduced.
Michelin has even thought about aesthetics. The PS 4 S includes the company’s new ‘Premium Touch’ technology that was launched a couple of years ago, which puts a velvety finish on parts of the sidewall, making the markings more obvious. There’s also a subtle (but hopefully effective) rim protector strip, which is a welcome addition considering Michelin is launching these tyres in 19 and 20-inch forms (from 225/35/19 to 345/30/20).
Effectively testing tyres is a tricky old business. On the morning of our test day in Palm Springs, Michelin sent us out on an incredible drive through Joshua Tree National Park (full report on that soon), which was amazingly fun, but not really intended as a learning experience. A session of follow-the-leader in M3s and M4s at Thermal Club’s tricky but rewarding circuit was memorable but again didn’t tell us masses given it was a new track to us, and the cars were all shod in the new Michelins giving no basis for comparison.
So, the important bit was the autocross test, done using a group of BMW 340s. Some wore the new PS 4 S hoops, others with competitor tyres, with all taking to the same tight and technical track with wet and dry surfaces, culminating in a hard braking test.
With a huge group of journalists to get through, the allotted time for the proper tyre testing ended up being relatively short, at around 15 minutes each. With that in mind we don’t want to make any concrete conclusions - and there’s also the fact that the sunshine was doing an annoyingly good job of drying out the wet section of the autocross test circuit, no matter how hard track staff tried to keep it moist.
However, the track time we did have still gave us a decent idea of how the PS 4 S performs against two of its closest competitors, the Goodyear Eagle F1 Asymmetric 3 and Continental Sport Contact 6. The Michelins feel just that little bit better in every regard - we’re not talking a drastic difference, but a noticeable one. In particular, during the low grip tarmac just after the wet section, both on the Goodyears and the Continentals - particularly on the former boots - the 340i’s back end seemed much more keen to step out. Quite dramatically so on the Goodyears.
Dry braking was another area where the PS 4 S stood out - the 340i felt more stable during the final stamp of the brakes that finished off the lap, and it consistently stopped short of the distance managed by the competitor tyres.
None of this should come as a surprise really, independent testing has shown the new rubber to be better than all competitors in pretty much every area. According to German independent tester TUV, PS 4 S-shod test cars pulled to a stop 2.41 metres sooner than the worst performing boots, the Bridgestone Potenza S001. In many cases, that could be the difference between hitting something/someone and not, although it’s worth pointing out the Goodyears were only 10cm behind. Perhaps most dramatic though is wear - according to Dekra a set of these will last twice as long as the heaviest wearing tyres of the major rivals, the Continental Sport Contact 6.
So in a way, the testing we did at Thermal Club served as more of a “told ya so” sort of experience, and quite an effective one at that. There is a ‘but’ coming, though, and it concerns price. You’d kind of hope the PS 4 S is demonstratively better than its rivals, because it’s quite a bit more expensive.
After looking up some prices to have the 225/35/19 rims on ‘our’ VW Golf GTI Clubsport fitted with PS 4 S hoops, we found that you’d be looking at £193.88 a corner. The same supplier wants £138.18 for the Bridgestone S001, and while the cash you’re saving getting the £150.98 Continentals will be offset by the heavier wear, Pirelli P Zeros are only a few quid more than the Contis, and should last almost as long according to that Dekra test we mentioned earlier.
You can’t really argue with what you pay for though, given that the Michelins do seem to be better across the board. It all comes down to whether or not you’re willing to pay the extra to unlock that little bit extra performance from your car, without going for a more aggressive, single-minded tyre. Here’s another way of looking at it: it’s probably going to cost you around £200 extra to get a set of PS 4 S over something else, and you’re unlikely to be able to make such a noticeable improvement to your car’s performance by spending that money on anything else. Other than driving tuition, perhaps…
We’d want a longer test to help us arrive at a more solid conclusion (if we can arrange that, you’ll be the first to know), but based on this introduction, these new Michelins do look to be a tempting option.