Damper sizing is a big thing. The diameter of the tube, length of the tube, and diameter of the rod, all get up someone's nose, and of course the program always wants to keep the cost down. The nice thing about these niche variants is that cost control more or less goes away. The problem with big pistons/rods is ride quality on smooth road, the stiction is more or less proportional to diameter. I vaguely remember that most of the stiction is in the rod seal, made worse by bending loads.. To get around that one of our retired engineers developed a rubber bushing that had very low coning rates but high radial rate to use at the shock to lower arm, I've been using that design ever since all over the place whenever I need a ball joint. Bronco/Everest has 6 of them.
Some of your problems, I don't have to fight. First, bending loads are minimized, due to through shaft dampers and rockers. Rod size has shrunk significantly, since we're no longer using the displaced oil to alter damping. Those two things alone have reduced stiction. Also, our piston seals don't have to last forever. They have to seal up for ~50 hours of use and then they're in a trash can. Obviously, they need to seal well enough to produce the necessary low speed forces, but reducing damper stiction is fairly high on everyone's list. (I have heard of inducing stiction to produce very low shaft speed force, but I've never played that game myself.)
The pressure lag of small diameter dampers are a real thing, but I have no idea of how to characterize it. Many years ago, I was running the Ohlins TT44, which was a spectacular damper with a 44mm main piston diameter. They had introduced a smaller, lighter version called the TT40, which was the exact same architecture with a 40mm main piston. I was with a strong and well-funded team (at one point, they did exist!). We had an exclusive program with Ohlins to develop these things with all sorts of 7-poster and hydraulic dyno time. We put a ton of work and money into these things. At the time, the only other car on them was the Audi R8's. They had so many advantages on that car that the dampers were fine to them and it saved them a significant chunk of weight. For us, dampers were one of the defining characteristic of the performance of the car, so any shortcoming they had was magnified. The TT40 never saw widespread use and it wasn't long before they abandoned the entire architecture and shifted to their TTX-style damper. Regardless of the weight penalty, I'd have no issue running a TT44 on _anything_, even today.
After a year of working on these things, we ended the season back on the TT44. I don't know how much the piston size influenced the struggles we had making those things work, but I've always thought that there must me something in it. It was essentially the same damper produced by the same people using a lot of the same parts and all of the same philosophies. It would have the same curves on a crank dyno and it would produce better grip and control numbers on the 7-poster. In actual use, though, it never felt as good and it never gave the driver the same confidence or feel in the car. Our better driver was able to win races and contend for the championship, but he always said you had to just trust the grip would be there, because you couldn't feel it. The lesser driver, who was still pretty good, was absolutely lost on the new dampers and we converted him back over to the 44's earlier in the process.
Our damper program was an absolute failure in terms of performance, but it was an interesting and instructive failure, none the less.
Edited by Fat Boy, 20 December 2022 - 17:16.