For fast electric cars, stopping their battery weight is important, too
My smart friend Doug Milliken sent me an email the other day to ask, “Whatever happened to 0–100–0 testing?” The 0–60 wars between Tesla, Faraday Future, and Lucid has got Milliken thinking that these all-wheel-drive electric cars must be accelerating nearly as hard (in g forces) as they can brake—at the limits of their tires in both directions of driving force.
Coincidentally, I’d just ridden in both the Faraday and Lucid cars during recent demonstration acceleration runs, and we were gearing up to test the Tesla Model S P100D, which Elon Musk claimed could zip to 60 mph in 2.3 seconds. Faraday is touting 2.39 seconds to 60 mph for its 91, and Lucid has 2.5 seconds for its Air. Let’s say 2.3, 2.4, and 2.5 seconds—all three warp-drive ahead of the 3.2 seconds we’ve recorded for the quickest piston-flailing five-seat sedan in our tested-performance list, an Audi RS7 from 2014. (We’re testing a new one soon.)
What’s making all three of these numbers so surreal is a confluence of technologies and architectures that—to give credit where it’s deserved—entirely traces to Elon Musk’s one-man makeover of how we perceive electric cars. Remember those “it’s nothing but a glorified golf cart” days? The sun set on that like a dropped bunker-buster bomb with Tesla’s original Roadster, which in our hands ErrrrEEEEEed to 60 mph in an astonishing 3.7 seconds. And it’s possible that the prototype two-speed version might have ultimately promised even greater acceleration, but the light-switch flood of max torque at the 1-2 upshift kept destroying transmissions. So the first lines on our blueprint for mid-2-second-sedan acceleration were drawn—an electric motor and a durable, single-speed reduction gearset.
More on the First Test review of the 2017 Tesla Model S P100D HERE.
The Model S that followed added two more parameters that would eventually but not immediately have equal significance to acceleration: a long wheelbase and a large, flat pancake battery between the car’s axles. On their own, neither of these is actually helpful at the dragstrip because they lessen weight transfer to the rear wheels. That’s the reason rear-engine and rear-drive Porsche 911s can embarrass what we think of as proper drag-racing cars with their heavy front engines and lightly loaded rear tires. In that regard, the Roadster’s tall, rear-biased, boxy battery (and its high center of gravity) was a helpful partner in pressing the Roadster’s rear wheels to the asphalt.
But the dual-motor Model S changed everything. The puzzle pieces suddenly fit. At its introduction, I was frankly under the impression that the new front motor, new front axles, and altered suspension were all presciently cooked into the car’s master plan from the beginning. Now, I’m not so sure. It was apparently their ultimate intention, yes. But in actuality, a lot of redesigning was necessary. And here at the dragstrip, at least, it was well worth it.
And that’s because the result is basically the perfect architecture for accelerating. That long wheelbase, low center of gravity, and nearly balanced weight distribution suddenly tee up blistering acceleration possibilities when all four wheels are driven. You don’t want rearward weight transfer anymore—in fact, now it’s the enemy of ideal.
The benefit from nearly doubling the tire footprint is pretty obvious. What might not be is an invisible phenomenon; the efficiency of a tire’s capacity to deliver grip diminishes as the tire’s downforce on the road rises. With AWD (assuming tire sizes that aren’t excessively staggered), you actually want to minimize weight transfer. That is, it’s way better to distribute the Tesla’s torque to all four wheels than theoretically stand the car and all its weight on two driven rear tires alone. Combine this with wheel-slip control that’s impossible in a gas car, and the result is a layout so ideal that it’s hard to imagine how to better it. The FF 91’s independent rear motors could ultimately respond even more precisely to their companion wheel’s slipping. But you’re basically left nibbling at the edges. Our test car’s special, lighter new wheels reduce rotational inertia, too.
The elephant in the room, though, is the weightiness of the big battery, which might not entirely be offset by aluminum construction and compact motors. That circles us back to why I raised an impressed eyebrow when I read Doug’s email. Because intrinsic to these AWD, electric-motor, flat-battery rocket sleds is the increased challenge of stopping them. In other words, the 0–100–0 test quickly captures both their accelerating and stopping attributes—the good and maybe the bad.
The 0–100–0-mph (0-161-0 km/h) test has a long history, most famously dating back to Carroll Shelby’s 1965 427 Cobra setting a time of 13.8 seconds with driver Ken Miles at what would later become Los Angeles International Airport. To be honest, I’ve always thought that number was pure propaganda from the wily old chicken farmer. In fact, many years ago I tried to replicate it in a 427 owned by Shelby at the Pomona dragstrip. With the great man himself exhorting me to try shifting at ever-higher revs (and his mechanic behind him waving “no-no!”), I finally blew the engine up trying.
With the Tesla P100D, we’re looking at the math: addition of the car’s 0–100-mph time and its 100–0-mph stopping seconds, captured during our routine testing. Partially, it’s an expediency because we didn’t have time to perform the whole 0–100–0 circus, which requires added equipment and lots of runs to get a representative example. But it also boils the matter down to what’s really the car’s essential performance. (Foot transition time from gas to brake pedal can vary a lot—from 0.2 to maybe 0.5 second.) OK, I agree. I’m a romantic, too, and I love the idea of actually doing the complete test. But this certainly makes for a clearer, more empirical picture of performance.
The result? The P100D captures a combined time of 10.2 seconds—that’s 6.0 seconds to 100 mph and 4.2 more to stop again. What’s that mean? Here it is below, listed in the context of cars we’ve similarly tested during the past few years:
|Order||Year||Make||Model||0-100-0 MPH, SEC||Curb Weight, LB|
|2||2017||Porsche||911 Turbo S||9.7||3,557|
|3||2017||Audi||R8 V10 Plus||10||3,642|
|5||2017||Tesla||Model S P100D||10.2||4,891|
|11||2017||Porsche||911 Carrera S||11.7||3,353|
|13||2017||Chevrolet||Corvette Grand Sport (8A)||12.2||3,479|
|15||2017||Alfa Romeo||Giulia Quadrifoglio||12.3||3,749|
|16||2017||Chevrolet||Corvette Grand Sport (7M)||12.4||3,464|
|18||2016||Ford||Mustang Shelby GT350R||12.5||3,711|
|19||2016||BMW||M3 (Competition pack)||12.9||3,646|
|20||2017||Chevrolet||Camaro SS 1LE||13.1||3,735|
|21||2017||Porsche||718 Boxster S||13.1||3,160|
|22||2017||Aston Martin||V12 Vantage S||13.3||3,677|
|28||2017||Chevrolet||Camaro 2LT 1LE||17.2||3,514|
Notice that you have to scan all the way down to the Alfa Romeo Giulia Quadrifoglio before you encounter the next five-seat sedan—and that’s 2.1 seconds slower and 1,142 pounds (518 kg) lighter. What’s amazing here is not just that the Tesla is fifth on our list but also how it’s swimming in the same pool as some outright sea monsters, such as the McLarens and the Mercedes-AMG GT S, while supporting a massive battery pack instead of a little gas tank. Oh, and it has those three rear seats and a cavern of cargo space, too.
To specifically address Doug’s original point about g forces, the P100D is delivering more than 1.0 g from 2.4 mph (3.9 km/h) to 46 mph (74 km/h) and the entire time it’s braking. That’s 5.7 seconds of its 10.2-second run—56 percent of it—above 1 g. Whereas the 0–100–0-mph test was always kind of a sideshow performance test you’d do as a novelty, going forward, when the FF 91, Lucid Air, and Porsche Mission E finally arrive (fingers crossed), it’s actually going to matter.