Hoffman900 wrote: ↑16 Jul 2024, 03:23
Holm86 wrote: ↑15 Jul 2024, 22:39
But bike engines has much smaller cylinders, much smaller valves so they weigh less, also they probably has less lift ie. less acceleration.
So bigger valves with more lift would need stronger coils than a small bike engine.
I know its doable with coils, but my guess is it'll be pneumatic, it's a track only car which as I understand needs a red bull crew to come along for a track day, so having a small nitrogen bottle that needs topping up won't be a problem
Why would it have more valve lift? Until you know what the valve lift is, that’s not necessarily true. It’s all a time / area calculation. Sure bigger cylinder, but also bigger valves.
One thing people forget is the more cylinders, the less velocity changes at the cam, and the more aggressive the lobe can be (higher derivatives) for a given valvetrain weight and / or rpm. A V10 is much smoother than an I4.
The only issue is going to be valvetrain weight.
I do know a lot of former pneumatic sprung valves engines being used in vintage racing do convert to coil springs.
What’s available now is light years better than the mid 1990s, and they don’t have to worry about leaking valve seals causing a dropped valve. This is a very common issue, especially with “collector” type cars that sit, which these RB’s will. There was a good article in Race Engine Technology about this a year or so ago and how these conversions are done.
Agree, and don't think many appreciate the, comparatively, steady creep of materials research, knowledge, manufacturing integrity, repeatability etc, etc that very undramatically brings progress and performance to mechanical hardware.
Almost unseen without some big headline title and catchy, of the day, descriptor to pull in publicity.
I don't believe casual observers have realised that you can't even turn the crank on an airspring valve engine, at all, without assurance that the valves are retracted and fully operational. Capable but very unyielding design given the likely ongoing use scenario.