How much pressure does a hydraulic clutch line see? Can a slave cylinder actuate a clutch pressure plate with reasonable air pressure? I could math it out with the system specs etc but am just looking for a quick answer really. Anyone tried it?
As air is compressible and fluid is not, you would need greater pressure to achieve the same work. Additionally, compressibility would make for less smooth and consistent action. Hydraulic mechanisms act like a solid link, (when not using accumulator or other wise dampened) You could use pneumatic system, but for something like clutch release, it would be more complicated than the simplicity of current hydraulic systems in use.
So to follow up on this... The plastic clutch alignment tool was not sufficiently accurate to allow my TKO pilot smoothly into the pilot bearing. I needed to actuate the clutch to allow the friction to align better while installing the trans. I ended up installing the clutch with manual fork and bearing. Then activating the clutch to install the trans. Removed the trans and bellhousing, pulled off the clutch fork, installed the hydraulic slave cylinder, and reinstalled the bellhousing. TKO slid right in after this alignment procedure. Incidentally the new 621 bellhousing was from southwest speed and it needed .021 offset pins to bring it within tolerance for alignment w the crank.