Just installed a Wilwood master and slave cylinder to Ford 302 with 11" Ram Clutch. 164 Tooth Flywheel. Takes 2 men and a small boy to push the clutch pedal down. moves the clutch fork back about 3/4-1". Don't have a driveshaft hooked up yet, but I don't believe the clutch is releasing. Seems like a tremendous amount of pressure on the clutch pedal. Anyone out there had this scenario - & have answers?? Thanks for the help!
What is the bore diameter of both the slave and the master ? The clutch master needs to be 3/4 or 7/8 " ...
As long as the fluid ines are big enough for the fluid to get thru them, it makes no difference whether they are 3/16" or 3". You need to brush up on hydraulics my friend.
I have a 3/4" clutch master for my Ford and am planning on a 3/4" or 13/16" slave cylinder, which should produce 1.3-1.4" at the fork. A gross mis-match could produce the problems that the OP is experiencing.
The fluid line is too heavy! He needs to fit a lightweight one. Another way to soften the pedal feel is to add high performance air bubbles into the system.
If you have a clutch fork why are you using a hydraulic clutch? It has been my experience that if you have room for a hydraulic clutch you have room for a mechanical clutch. I have had so much bad luck with hydraulic clutches and have had to retrofit mechanical linkage to many. The last one had such a stiff clutch that it ruined the internal release bearing. The problem was the guy chose a racing clutch with an HD pressure plate. To make it worse the guy who installed the pedals shortened them, reducing the pedal ratio. The stroke was barely enough to disengage the clutch with the pedal pushed all the way to the floor. All in all it was a bad combination and ended up bleeding its vital fluid all over the floor. The fix was to remove the racing clutch and replace it with a standard clutch. Remove the internal release bearing and install a new input sleeve on the trans. Install a clutch pivot ball in the bell housing and a throw out arm. Install a modified SoCal Speed Shop 32 Ford clutch linkage kit. Now the clutch is a bit stiffer than a stock one would usually be because of the short pedal ratio. But now you don't get leg cramps while cruising the fairgrounds. My advice "Friends don't let friends go hydraulic" Go mechanical while you are still building the car because retrofitting after it is all done (paint and powder coat) just plain sucks. Jim Ford
So you basically have 2 problems. 1st is that the pedal is too hard to push. 2nd is that you aren't getting enough travel at the fork. Both of those are force over distance problems or ratio. THere's a big picture problem with this though, if you make the pedal easier to push the distance that the fork moves will be less. They covered all of this stuff back in 8th grade, levers and ratios. You trade force and distance to move things. You have several in your clutch set up. First is the clutch fork, the distance from slave cup to pivot to release bearing is a leverage ratio. Second is the bore sizes of your master and slave cylinder, another leverage ratio but hydraulic. Third is the stroke length of the master and stroke needed at the slave, this is the volume moved vs the volume needed. Fourth is the pedal ratio, the distance from pivot to master hook up and pivot to pedal pad. When it comes to pedal ratios the distance available for the pedal pad's motion is pretty darn critical. So if you can fill in those blanks it should be really easy to spot the problem
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