djos wrote: ↑21 Apr 2022, 02:36
Hoffman900 wrote: ↑21 Apr 2022, 02:29
djos wrote: ↑21 Apr 2022, 01:55
Did you even watch the video?
The Pikes Peak Tacoma has giant Venturi tunnels (shown in the video) and Rod Millen even says (in the video) that the 3rd spring setup was specifically to stop the car from bottoming out and choking the flow to the Venturi tunnels.
As someone who lives within eyesight of Pikes Peak, those vehicles do not go up it anywhere near the speed of a F1 car, the road is rough due to horrendous freeze / thaw conditions, and wings / tunnels are outsized due to the 1) lower speed 2) lower air density.
None of it is relevant to F1 or their porpoising phenemon.
Indy Car is interesting because they have been averaging north of 220mph around ovals for decades now.
That's completely incorrect, any vehicle with Venturi tunnels needs to control its minimum ride height or risk porposing, that's just a fact. It doesn't matter if you are doing 100mph or 200mph, porposing needs to be prevented if you want a stable and fast car.
Your assumption is that porpoising is caused by choked flow. If this is true, then the squatting of the previous generation of cars to reduce drag would have caused porpoising, and they didn’t.
It’s pretty much been said by all those who actually have a clue and spoken publicly; Jean-Claude Migeot, Peter Wright, and James Allison that choke flow is NOT the issue. I am not sure why people are yammering on about it still. Every single person in the media talking about this have no idea. They are journalists and pundits, not aerodynamicists, not engineers, and none have designed even something as simple as a Formula Ford.
As for the ride height, you need to control it on everything, from NASCAR, vintage Trans Am cars, to rally cars, to flat bottomed formula cars, to venturi F1 cars. It’s part of the go fast equation.
The heave spring set up came to be to control vertical downforce load while still being able to run a soft enough suspension for mechanical grip.