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Comment by fivefive55 | Hacker News Reader

It's not so much 'lag' that people notice as much as the torque roll on. Even a supercar doesn't deliver 100% torque the second you hit the throttle, the RPM has to build to increase the torque, hence the reason torque and HP are on a curve. Electric on the other hand has ALL the torque available ALL the time. Generally they actually have to limit it for takeoff otherwise every Tesla would just roast the tires if you slammed the throttle.

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What we're now describing is more or less the power and torque curve as you rightly mentioned. My worry here is that we're kind of categorizing all internal combustion engines as having the same kind of power/torque curves when in fact a lot of internal combustion engines are very different from each other.

Some engines are capable of delivering 100% of torque the second (within a couple 100ms) of hitting the throttle. To name a couple:

1. The Mercedes M278 twin-turbo V8 makes 700NM of torque between 1,800 and 3,500RPM. In other words, 700NM of torque is available from little above idle.

2. BMW B58 single-scroll turbo i6 makes 500NM between 1,600 and 4,500RPM.

Other turbo charged engines, such as those in supercars, have different kind of turbos turned for a more linear torque and power curve to better replicate their N/A predecessors, such as the McLaren M838TE which makes 620NM between 5,500 and 6,500RPM.

Lots of different engines out there with all kinds of different characteristics and power/torque curves.

You're definitely right, it is getting to the point of semantics when it comes to comparing the high end of internal combustion to electric. I mean, even very old diesels could hit their peak torque in the 100s of rpms. Even still though, a couple 100ms to full torque is still more than literally instantaneous torque with electric. That also applies to the 'low end' electric cars as well. They're really good at getting your head to snap back into your seat, but once you're moving the benefits really drop off a cliff. Just like the torque and hp 'curve'(cliff) of an electric car actually.

a turbo engine takes some amount of time to spool up the turbos and produce the full torque. sometimes that time is very small, but it is there.

As a practical matter, the most powerful Porsches and Teslas are both going to be hitting the traction control pretty constantly during hard acceleration from a stop. Their performance changes on racing slicks, I'm sure. A gt2 RS on racing slicks recently did less than ten seconds for the quarter mile with some minimal modifications at a drag strip. (Which is a crazy use for that car, but still)

It's a measure of how amazing the Tesla's performance is that you need something with race car-like specs to compete. On the other hand, that only holds true for about the first quarter mile. It's not going to keep pulling hard until 200mph. The roadster will, perhaps, someday.

For acceleration.

That's 1 part of driving, it's just the part Tesla chosen to highlight because it's where electric cars have an advantage.

They are also heavier and tend to overheat if pushed.

Even in a 1/4 mile the Tesla is somewhere in the 10-11 second range. That's insanely fast, but it's not reaching the levels of purpose built drag racers or even some production cars.

> That's 1 part of driving, it's just the part Tesla chosen to highlight because it's where electric cars have an advantage.

It's also the part everyone driving on a public road notices and appreciates. There's a reason zero to sixty and quarter mile numbers have always been so widely quoted.

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