At very small valve lifts as the valve lifts off the seat, then annulus between the two, sure, but I can tell you they didn’t have the technology to measure that when that graph you shared was made.gruntguru wrote: ↑08 Jun 2023, 00:22I would be interested to see more detail on an exhaust port that doesn't choke. Cylinder pressure at EVO is several times port pressure and a big valve still has a small curtain area when it is just off the seat.Hoffman900 wrote: ↑07 Jun 2023, 14:55Furthermore, Honda showed even with Naturally Aspirated engines that the port may or may not choke, depending.
http://www.f1-forecast.com/pdf/F1-Files ... P2_10e.pdf
What’s the SOS of exhaust gasses when first cracked open on a current Formula One engine?