doing some research on installing a hyd clutch. I was thinking of a slave from a 61, 62 chevy truck, easy to make a bracket for and you can still get them from Rock Auto. I looked up specs and they come in a 1 inch and 1 1/16 bore. I figured they'd be closer to 3/4. I'd have to find a matching MC, would you all go with a Wilwood or does anyone know of a better one? I'd be using a 10.5 or 11 inch clutch with the stock throw out bearing fork.
What are you working on? What's the year make and model your trying to convert to hydraulic? Is the clutch you currently have to stiff? What's the thought behind getting rid of the current set up?
Years ago on a customers truck, I had a local Auto Parts guy who still had books including pictures...I asked him to look for a stand-alone single clutch master(bore size) to match that 60-62 stock Chevy tandem brake/clutch master. His book showed pics of a few with the correct bore, and I picked out the one that attached to the firewall the way I needed. I think it was a Cardone Brand book, not sure.
This will be a future project I'm collecting parts for. 327 with a 5 spd behind it, thinking about the AX15 trans since it's stronger than the Camaro BW 5 spd, depending on what I find. Going to use a old style bell housing, 11 inch clutch, Novak makes an adapter to mate the AX15 to a early GM bell housing, I seen one in a 69-72 chevy truck with the factory bell housing and a AX15 out of a 98 or so Dakota that made a nice package. I'll use the stock type clutch fork and bearing. I don't want a hyd throw out bearing and I don't want something that will fail every so often.
Rich, this is what I've found. Dorman, 1 in. CS19097, 1 1/16 CS36124. Centric, 1 in. 13882001, 1 1/16 13882002.
I used this slave.............. https://www.autozone.com/drivetrain...uralast-clutch-slave-cylinder/577913_172393_0 For a M/C I went with a matching '62 Chev pickup unit. Don't forget to swap the plungers side to side...……. https://www.autozone.com/brakes-and...aster-cylinder-brake-system/42914_478256_3508 I originally used a Thunderbird TurboCoupe slave with a 7/8" bore 'cause I had one laying around. I could hardly push the pedal down. So, I swapped it out for a proper '62 Chev pickup slave w/1" bore and now it works like a real hydraulic clutch. Very easy on the lower extremities! It's amazing what an eighth inch of volume will do! For a connecting line I used a length of SS braided brake line...….. https://www.summitracing.com/parts/...MIyp3cn6uy4AIVz8DACh3Z0Ai9EAQYAyABEgJau_D_BwE
Mike: Thanks for the reply, I thought there was only one size. It's good to know there is an option. Rich
Myself, I wouldn't use the Dorman, I quit using all their stuff here at the garage. Their electrical is completely junk.
A quick look at this AX15 sounds like an interesting option. Lots of Jeep info, though. What’s your plan for fitting it to a 2wd driveshaft? Speedometer drive options? Sent from my iPad using The H.A.M.B. mobile app
I used the entire bellhousing and slave assy out of an early 60s chevy Pu in my model A , the one with the pass side clutch fork. If you want to run a dual res master for the brakes ,I would just use a 1" bore master for for the clutch. It's a clean set up with no adapters needed for the slave.
I have used a t5 transmission out of a 89 Camaro with the original bellhousing behind a Goodwrench 350 . I matched up the bore size of the master with the bore of the slave ,3/4 I think and bought a clutch master mounted in a hanging pedal assembly from cnc .Chuck Neal corporation they sell all sorts of pedal assemblies . It has worked well for 6 years in a 37 Chevy
The fluid displacement volume of the master cylinder should be approximately 10-15% greater than the volume of the slave cylinder. Bore diameter determines stroke, so the mechanical apparatus between pedal and master cylinder creates desired pedal travel. Finding the cylinder volumes makes the hardware choice easier, then design the pedal assembly so as to correspond to cylinder stroke. PS : The mechanical travel required to disengage clutch determines slave cylinder, so the complete system starts with the clutch.
I don’t doubt what you say about the 10 15% difference in master and slave . When I used the t5 out of the 89 Camaro I parted out the wreck . I copied the bore size as close as possible on the master to the oem size as I was already using the oem slave . You are right though I had to play around with the hanging pedal assembly to get the pedal travel right . The hydraulic set up feels really good if you take the time to set it up right . I also like it better when the set up has the slave external of the bell housing . If you are fooling around with different masters and slaves try and figure out the hydraulic fittings on each one and then take them to a competent hydraulic line making outfit.
I used a 2006 Ford Focus Master cylinder because the outlet points straight down and a Toyota (not sure what, but it came from Rock Auto). Both are 3/4" bore and the feel and stroke are about right. I had the local Napa make me a hose, fabbed my own brackets and have been driving it since 2011 or so.
The AX15 comes in dodge dakotas, v6 and v8. It also comes in Jeeps, 2WD cherokee. Just get the yoke for the trans. Novak makes an adapter to mate it to a chevy bell. The shifter is in the front of the tail housing. A lot of rock crawlers use them. They have a low 1st gear but I'm planning on a 3.73 and a 31 inch tire. I know how the diameter of the slve and MC affects stroke, I was just wanting to make sure I have enough stroke and I'll install a stop so nothing bottoms out. I've seen several use a 1 inch MC and a 3/4 slave.
You would think bigger is better....A 1" master cyl pushing a 3/4" slave...BUT in the world of Hydraulic pressures a SMALLER master bore will put out more pressure. With a 6 to 1 ratio on your foot pedal, a 3/4" master with a 1" slave ........ your left leg will love it !
I run a 3/4" Wilwood master and a 7/8" external Speedway slave. I had read up on them and that was a recommended master-slave ratio. It works quite well, easy pedal pressure.
The relevant parameter is not volume, its the cross-sectional area of the slave piston acted on by the hydraulic fluid. Fluid has __ psi based upon master cylinder piston area, lever arm of pedal, and force on pedal pad. Bigger slave piston area = more pushing force by slave. Equation is psi (in) x sq inches slave piston = lbs pushing force.
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