There was a cliffhanger in our last update. Seven months into our year-long test, we had just completed the M2’s first scheduled maintenance and swapped out the abused, stock Michelin Pilot Super Sport (PSS) tires with just-released Pilot Sport 4 S (PS4S) successors. The improved ride quality was immediately noticeable. There’s an almost buttery smoothness to the way the new tires go down the road, and they’re quieter, too. Also welcome is the way the car initiates a turn with newfound alacrity; it’s crisp and precise like never before. That isn’t uncommon going from tires with 11,000 hard miles on them to brand-new ones, but our friends at Tire Rack agreed when rating the PS4S against its two closest competitors. Would we see a difference in outright performance?
| TEST DATA | Michelin Pilot Super Sport | Michelin Pilot Sport 4 S |
| ACCELERATION TO MPH | ||
| 0-30 | 1.7 sec | 1.6 sec |
| 0-40 | 2.5 | 2.3 |
| 0-50 | 3.3 | 3.1 |
| 0-60 | 4.2 | 4.1 |
| 0-70 | 5.5 | 5.5 |
| 0-80 | 7.1 | 7.2 |
| 0-90 | 8.9 | 9.1 |
| 0-100 | 11.1 | 11.4 |
| 0-100-0 | 15.2 | 15.4 |
| PASSING, 45-65 MPH | 2.0 | 2.1 |
| QUARTER MILE | 12.9 sec @ 107.1 mph | 12.9 sec @ 106.2 mph |
| BRAKING, 60-0 MPH | 106 ft | 101 ft |
| ATERAL ACCELERATION | 0.99 g (avg) | 0.99 g (avg) |
| MT FIGURE EIGHT | 23.9 sec @ 0.83 g (avg) | 24.0 sec @ 0.83 g (avg) |
| 1.6-MI ROAD COURSE LAP | 1:24.78 sec | 1:23.34 sec (-1.44 sec) |
Compared to acceleration our M2 made on its then-new PSS tires, the PS4S tires did launch quicker and stayed in the lead up to 60 mph until it inexplicably began to fall behind but then made a final charge to literally tie the quarter-mile time. Strange, but we’re talking only tenths of a second here and there. Are the new tires grippier but heavier? Tire Rack says the fronts are the same weight (23 pounds), and the rears are each a pound heavier (27 pounds)—not enough of a difference to make a difference. Similarly, on our figure-eight test and skidpad, the results were nearly identical with only a tenth of a second separating them. The good news? In braking from 60 mph, the PS4S tires required just 101 feet (5 fewer) to stop. The final test would be lapping a track. Our last outing at “Streets” produced a 1:24.78 best lap, but on the PS4S tires, the same car with the same driver shaved 1.44 seconds for a 1:23.34 lap time. That’s huge on a 1.6-mile track. After lapping, Randy Pobst said that the PS4S tires’ braking advantage was noticeable and that the M2 wasn’t twitchy in the high-speed sections or “pushy” in the low-speed ones. He felt the car was better balanced between understeer and oversteer. Currently, the new PS4S tires are less costly than the PSS for the M2. If you’re in the market for a new set of shoes, we’d recommend saving a few bucks and trying them out.
MORE ON THE BMW M2 RIGHT HERE:
- Arrival
- Long-Term Update 1: Break-In Miles Complete
- Long-Term Update 2: Taking it to the Streets
- Long-Term Update 3: Oil, Scheduled Maintenance, and New Shoes
| 2017 BMW M2 | |
| BASE PRICE | $53,495 |
| PRICE AS TESTED | $57,795 |
| VEHICLE LAYOUT | Front-engine, RWD, 4-pass, 4-door coupe |
| ENGINE | 3.0L/365-hp/343-lb-ft* turbo DOHC 24-valve I-6 |
| TRANSMISSION | 7-speed twin-clutch auto |
| CURB WEIGHT (F/R DIST) | 3,506 lb (52/48%) |
| WHEELBASE | 106.0 in |
| LENGTH x WIDTH x HEIGHT | 176.2 x 73.0 x 55.5 in |
| 0-60 MPH | 4.2 sec |
| QUARTER MILE | 12.9 sec @ 107.1 mph |
| BRAKING, 60-0 MPH | 106 ft |
| LATERAL ACCELERATION | 0.99 g (avg) |
| MT FIGURE EIGHT | 23.9 sec @ 0.83 g (avg) |
| REAL MPG, CITY/HWY/COMB | 18.7/29.8/22.5 mpg |
| EPA CITY/HWY/COMB FUEL ECON | 20/26/22 mpg |
| ENERGY CONS, CITY/HWY | 169/130 kW-hrs/100 miles |
| CO2 EMISSIONS, COMB | 0.87 lb/mile |
| TOTAL MILEAGE | 14,340 |
| AVERAGE FUEL ECON | 20.8 mpg |
| UNRESOLVED PROBLEMS | None |
| *369 lb-ft @ 1,450 – 4,750 rpm in overboost | |
The post 2017 BMW M2 Long-Term Update 4: Hot Lapping our M2 on Fresh, New Tires appeared first on Motor Trend.
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