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Comment by js2 | Hacker News Reader

Impressive but for reference, about half the acceleration of a Top Fuel dragster, which are also still getting faster.

Here's Brittany Force who holds the current records (fastest time, fastest speed):

https://www.nhra.com/news/2022/brittany-force-sets-national-...

0 to 338.43 mph in 3.665 seconds over 1000 feet. (The cars got too fast for 1,320 feet and have been racing 1000 feet since 2008.)

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The dragsters need to have a complete engine tear-down after nearly every run, regularly explode in a giant ball of flame, etc.

I thought maybe this was a superficial tear-down but nope, it's a whole heckin teardown and measurement of components and relubing and cleaning and etc.

https://www.youtube.com/watch?v=I1RYmUxUqso

Also the end of this video gives an awesome perspective that really shows the insane speed of these cars.

They pulled some type of rotary pump thingy out of that monster that ran the entire length of the engine. I'd never seen anything like that and had to look it up. It's a supercharger; a glorified air compressor. That air pump uses more HP than your average supercar.

Holy hell.

They also blow a lot of that power out of the exhaust pipe. I bet in terms of efficiency per km/h/s the electic go-kart wins.

The exhaust provides downforce though.

8G's max acceleration and -6G when they hit the brakes (using a parachute)

11,000hp!

Electric: 0-60mph in ~0.9s

Top Fuel: 0-60mph in ~0.4s

Wow.

yeah top fuel is bonkers those engines literally eat themselves alive down the track within milliseconds! hardcore!!!!

bonkers is a good word. I've never enjoyed drag racing and top fuel cars are incredibly wasteful and yet, one has to admire and stand in awe at the engineering. Every single aspect of those cars is off the scale insane and then some.

They use spark plugs, driven by more amps than an arc welder. But the plugs melt away in just a few instants, the rest of the run the engine is dieseling from the extreme heat.

The supercharger alone takes so much power to turn that barely any car on the street could even run it.

The tires are quite something, watch slow motion videos.

https://autowise.com/a-nitro-burning-top-fuel-engine-the-mos...

Electric: 0-60mph in ~0.9s Top Fuel: 0-60mph in ~0.4s

That's students though, students at ~0.9s! Wow.

I wonder if they'd go any faster if the rules allowed overhead cams!

Even though these cars have disastrous efficiency and need to be completely rebuilt after every run and have backwards rules that leave them using "ancient" technology, I can't help but be awed by the effectiveness of the sledgehammer approach.

I wanna know how they fare when the vehicle has to do 10 races on the same power train. I bet it would be a lot closer.

Aren't electric cars bound to beat any dragster car eventually? You get max torque instantly.

Depends on how fast you can release that energy from the batteries. Not as instant. Chemical explosions are rapid.

They could boost with super capacitors.

Super capacitors are highly overrated by the general public. They really aren't that much better than lithium ion except for in a very narrow power/time bandwidth.

The comment I was responding to was lamenting the potentially slow speed of chemical reactions in batteries, so I recommended super capacitors specifically for the case where a higher rate of discharge is required. I agree lithium is potentially good enough there, I am merely speculating on solutions in the event that an ultra powerful vehicle really could exceed lithium’s capabilities.

As for the general public, I can’t say. I use super capacitors in the power system for my solar powered robot and I love them. Through that experience I have realized they have plenty of other applications.

> except for in a very narrow power/time bandwidth

Which is exactly the scenario we are discussing. Drag races are only a few seconds.

To me, this is lacking context enough that it appears to be an automated comment.

Combined flywheel and homopolar generator — a smaller version of the device Oliphant built at the ANU.

Drag cars are slipping a clutch for the first 800 feet or so. Totally traction limited, not torque/power limited.

Thinking out loud, but it's mostly power to weight ratio isn't it?

With batteries currently being less energy dense than fuel, can an electric car be faster?

Now there's more to the vehicles than just the energy supply, so I suppose if an electric car could harness battery power more efficiently (i.e. with less weight) than an ICE powered vehicle, it could be faster?

I was sure you made a typo and meant 10000 feet, instead of 1000. But after checking, yeah, it makes sense to make the track shorter to avoid the cars reaching even more insane speeds.

they've been playing this trick with top-fuel dragsters for decades - the "speed" was measured far before the end of the course. I think it was to keep the speeds below 300mph to help with track insurance.

I don't think it's a "trick", it's purely for safety reasons. The distance change was made following a fatal crash.

the trap speed was before the 1/4 mile and measured a speed lower than the time at the end

They had a choice, lengthen drag strips everywhere or decrease the length of the race. Because physics / braking distance.

the trap speed was before the 1/4 mile and measured a speed lower than the time at the end

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