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Comment by ehnto | Hacker News Reader

The turbocharged peak power was said to come at 7500rpm, with peak torque of 443lb at 3000rpm which is pretty good! I would expect NA torque to be somewhere in the mid 200lb region, which is comparable to the 2020 Nissan Pathfinder in both V6 and I4 petrol variants. The I4 Turbo diesel obviously putting out far more torque at lower RPM making it more usable. But there is no doubt that Koenigsegg has made a huge leap here. The only missing datapoint is reliability. How aggresive is the tuning on the engine to get these numbers and does that effect it's long term robustness?

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Just look at the cars they currently make. Highly tuned supercars not economical commuter vehicles.

skeptical tech from one will transfer to the other.

I used to work for a supercar company, our unit price made certain tech possible, not even thinkable for mass-auto.

You're right, I wouldn't expect this level of performance from a commuter car with similar displacement.

That said, Hyundai recently developed their Continuously Variable Valve Duration system, which looks to solve changing valve duration more affordably in an all mechanical system.

There are a few of these valve systems around (if i recall correctly they've been around for decades, really).

BMW started putting them in motorcycles recently.

You might be thinking of VVT or variable valve timing, which changes when the valve opens. Variable valve duration changes for how long it opens for and I think is a recent innovation. The latter allows for more efficiency as the engine at different speeds and loads requires more or less lift duration. It's also continuously variable across the RPM/load table, wheras most VVT systems just swap between two different activation timings and as such are always a compromise somewhere in the range.

I have also seen a system that swaps between two different cam lobes entirely, offering two different cam profiles which can also vary valve duration and not just timing, but you're limited to two settings again, where these newer systems offer complete variability.

No, these are not VVT.

I might be misremembering, but I thought the new bmw system was dual cam - so exactly what you are suggesting, a trade off in the middle, but not vvt.

At any rate, variable cam systems in bikes have certainly been around since the early 80s with one of the 400c cbrs. They never really caught on but there are a bunch of variations.

I should have been more explicit, but above is not incorrect.

Honda had VTEC engines even back in the 80s, they physically choose between (three, if I recall correctly) cams.

These are not pure VVT systems, although they are not continuous like the Hyundai.

Not with variable duration. Hyundai is the only car company doing that now.

Worth noting that Rover apparently had a VVC system [1] that allowed the duration of intake valves to be continuously varied all the way back in 1995.

[1]: https://www.autozine.org/technical_school/engine/vvt_4.htm

Like I noted, not the same as they hyundai system, but not VVT either. And bikes, not cars.

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