Some people are obsessed with size. You know them, their car has more pistons in each brake caliper than their engine. Each brake disc looks like a flying saucer. Meanwhile, their brake pads are rated to withstand re-entry into earth’s atmosphere. It’s likely overkill.
All that hardware means nothing if the tyre’s grip levels aren’t as large. As we’ll see, tyres can vary brake performance, along with distances, by wild margins. To test this, we’ve designed an ‘emergency’ braking zone for Luffy to use on every second return from the slalom.
It’s well away from the dragway’s sticky stuff and will involve Luffy dialling up an indicated 110km/h as he approaches the entry gate. He then will bury the brake pedal to engage full ABS from 100km/h to rest. We measure the distance it takes to stop three times, then average the result.
As Luffy cycles through the contenders, the Hyundai’s spoiler-mounted brake light flashing during hard stops, Continental shows it has evolved the ContiSportContact 5P’s braking prowess to new levels with its new SportContact 6 flagship. It pulls up a ruler’s length shorter than the Dunlop.
Even with a cool-down between each run, our control data reveals braking performance drops off slightly as the day goes on. While Luffy reassures us the i30 N’s brake pedal stays firm, surface temperatures rise steadily in both the sun and shade from around 23 degrees Celsius to around 30. Ambient temperature peaks at 26 degrees.
Because this has most likely handed our first control run an advantage over the last (it stopped 39cm shorter), this slightly tweaks our finishing order. Linear regression splits the tied placings in seventh between Laufenn and the Nitto. It also swaps the Goodyear and Pirelli in respective fourth and fifth positions, the later run Pirelli gaining the formulaic advantage.
As for the rest of the pack, Kumho’s PS91 cements its dry-braking performance with an unchanged third to replicate its result in last year’s test. Meanwhile, the pack’s tail-end is more than three metres away from the top spot.
Most notable is the Achilles, which needs an extra seven metres than the Continental to reign in the Hyundai’s 1400kg-plus at 100km/h. It’s a chilling statistic. That distance spans longer than a Mercedes Maybach S600 Pullman. Lose a game of chicken with a roo, or a set of yellow traffic lights, and those seven metres could cost you more than last place in a test.
Getting to grips with MOTOR Tyre Test 2018