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Comment by pmcollins | Hacker News Reader

It has a two-speed transmission, which should help with high-speed performance. https://insideevs.com/news/343827/porsche-taycan-2-speed-rea...

But one of the advantages of an electric car for me is the possibility of no (variable) transmission. I don't want clutches that are constantly wearing down as I drive. For me this is not about money or maintenance headaches, but about elegance.

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Given that a standard ICE vehicle clutch will usually make over 150k miles before needing replacement, I can't see any reason to think that this will be 'inelegant' - it would appear to boost performance nearly everywhere, and they will not be 'constantly wearing down as [you] drive' - they'll be electronically controlled as part of the transmission and optimally maintained as a result.

While I agree the simplicity of a single speed no-clutch electric drivetrain is appealing, I don't think that should preclude using different systems if this means optimum performance overall.

Wear should never be an issue considering how (relatively) rarely the car would need to shift. It will be used at higher speeds so it won't shift that often. Chances you swing between high and low speed (over/under 100+Km/h probably) that often are small.

There are efficiency and performance advantages to having a multi speed gearbox for an EV. So far about 5-20% improved efficiency for 2 to 4 speed gearboxes. ZF insists EVs might end up using 4-speed gearboxes eventually but I can't help think they're biased in proposing this.

you only need clutches when you're stopped - to engage an moving/idling motor to stationary drive wheels.

Electric cars don't need clutches because their motors stop too

Probably the car will switch between gears while in motion. It seems to me that it would be difficult to do that smoothly without a clutch.

It is only important to carefully match the revs when switchen gears. Electric cars with electronic control can be easily programmed to do so.

Put an encoder on both shafts, have a control loop match the speeds, adjusting as frequently as desired, easy.

Running electrical engines at lower speed should in theory reduce wear, especially at autobahn type speeds.

If you’ve ever driven an electric performance car one of the most disappointing things is comparing 30–90 vs 0-60. Arguably the latter is more important because the typical on-ramp is generally 30 mph and highway traffic around me is traveling at 75+

That's why dual motors are nifty, you gear them separately (front for cruise, rear for accel) and you get better efficiency, handling and traction.

Disappointing, and 30-90? Nah. Even my RWD non-performance Model 3 with only 250hp or thereabouts 'feels' faster than my 300HP Golf R did from, say, 70-100mph. I admit, it absolutely feels relatively "out of breath", so to speak, above 95mph, but that's nothing HP can't solve.

I'm not saying there's no need, ever for a multi-speed transmission in an EV, but for 99% of the vehicles, it's likely pointless.

Do you like the Model 3 more than the Golf R?

That depends on what you mean. My knee jerk reaction is, no, I don't. But they're different cars for different purposes for me (as an enthusiast). I sold the R around the time we bought the Tesla because the only thing we needed less than 1 $40k car is 2 $40k cars. (We've got 4 cars at the moment, though I'm currently at CarMax trying to get rid of one of them).

The Model 3 is the first appliance car I've owned. But I went into this eyes wide open; it was the right decision at the time and it's still the right decision. The R I basically stopped driving when I got a new job where I biked to work for a year. The Model 3 was a replacement for my wife's 175k mile Subaru, and we bought it immediately after my company was acquired and we started carpooling together. The 3 is a better commuter/appliance more suited to 2 drivers who trade off, cheaper to run, gives us HOV lane access on the rare occasion where one of us drives solo, and my wife hadn't driven stick since she lived in Australia many years ago so she didn't really show interest in driving the R.

The R was my (other) fun car, with all the euro goodies on it. It was fantastic everyday runabout, fun car, roadtrip machine that could eat miles like nobody's business. The 3 is, again, an appliance. I don't really like sedans, but I wanted an EV, and I like Teslas, but could never justify spending the coin for an S.

Given infinite money and space, I'd still have the R, too. Though I'd probably never drive it, because it's so easy and convenient to just hop in the Tesla and go, any time, anywhere. It never has to warm up, it never needs me to stop at the gas station before I run my errands, hell, I don't even need a key.

A good set of performance tires really wakes up a 3. Try a set of Michelin Pilot Sport A/S 3+, (or 4S if you never see snow). I rented a 3 LR RWD for a few days and decided not to buy, but then drove the Performance and had to have it. Yeah, the brutal acceleration was part of it, but the biggest difference is how much sharper the handling is. And this is mostly down to the squashy super efficient tires on the base models masking the capability of the car.

While this is good advice in general, this literally applies to every performance car (and even every car period). The Model 3 isn't unique in benefitting from better tires any more than a Golf R.

Also, the A/S 3+ is an obvious compromise for people that don't want to rotate their tires seasonally. If you're going to recommend tires for performance, the PS4S is a good choice and then get a separate set of tires for winter. In other words if you think the tires make a difference like you wrote, you're selling yourself short driving on all season tires. Do yourself a favor and buy a set of summer tires if you're serious about how your car performs.

No gearing is bad for performance and inelegant. Tesla's cars should have a top speed over 220 given their power and acceleration. They're all limited to ~140 because no gearing.

The motors start to get inefficient even around 80mph. Telsa's have amazing 0-60 performance but get beaten by many cars on a highway roll because of no gearing.

Mid 160’s actually

Maybe, but that's above their rated specs. P100d starts out with 500 hp but also weighs nearly 5000 lbs. By 80mph back EMF has probably taken power down to about 300hp.

Essentially, at highway speeds, telsas are slower than the average pickup truck. Not as impressive as the 0-60 times

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