The Porsche Mission E concept, if it’s headed to production, could end up being quite the rival to Tesla Motors' [NSDQ:TSLA] Model S P90D.
And just as in the Model S, if you’re looking for a transmission in the Porsche you won’t find it. Of course you won’t in any of today’s pure battery electric cars on the market either.
It’s an idea that’s hasn’t been completely written off, but most automakers are finding that keeping a transmission—and its extra weight, complexity, and mechanical losses—out of the picture is a good thing. Tesla considered multi-speed transmissions and then abandoned the idea. And while some suppliers have hinted that transmissions are being considered for EVs, even the German supplier ZF—a company that once put nearly all its cards in transmissions—concedes that one gear is enough for conventional electric vehicles.
Is one speed enough?
Of course, the Mission E concept that Porsche showed at the Frankfurt Auto Show last month, with its speedy 800-volt charging system, 310-mile driving range, and super-low packaging, isn’t intended to be a conventional electric car, or a conventional performance model.
Porsche claims that the Mission E, which has a separate motor for the front and rear wheels, plus torque vectoring on an individual wheel basis, can get to 62 mph in 3.5 seconds and to 124 mph in less than 12 seconds. While that’s not as quick as the Tesla Model S P90D, Porsche hinted that the Mission E could be the fastest all-electric car yet, in terms of maximum speed.
That would require beating the limited 155-mph top speed of the Tesla Model S P90D. And it had us asking questions about whether one gear is still enough, from the firm, controllable launch characteristics they need all the way up to top speed—within an electric motor’s typical maximum of 16,000 rpm or so.
The response, from a Porsche official, was: “Who said that the motors are on the same ratio?”
McLaren 650S vs. Tesla Model S P85D
Broadening the difference, tuning the dynamics
It’s a strong hint that Porsche is looking to expand the difference between the reduction ratios of the two motors. That’s a strategy already employed by the Tesla Model S P85D and P90D, by the way (and, we’d assume, the Model X as well), with a slightly taller gear in front in Tesla’s case, although the over-the-road differences there likely aren’t all that significant.
But we’ll also wager that a more dramatic difference in reduction ratios is a key to the Mission E’s sub-eight-minute time on the Nürburgring Nordschleife—and in it offering a dynamic personality familiar to Porsche fans.