Hydraulic Clutch, This works GREAT! Options

[PRS914-6]

Seems like there is always interest in converting to a hydraulic clutch. Using a 911 clutch gives a bit of a stiff pedal but my biggest complaint was I didn't like the modulation and feel especially using a performance clutch disk. The 914-6 cable is much smaller in diameter than a 911 cable and aggravates the problem. In addition, my first gear is really tall and with a clutch that felt like it was on/off was a little annoying and down right scary when stopped on a hill with someone on my ass.

I picked up a new generic master cylinder and pull style slave (available at most any buggy shop for under $150.00 I also picked up a 4 ounce remote reservoir.

I made a plate that fit under the brake master cylinder and a bracket that fit on the side cover of my 915 tranny and ran the hydraulic lines down the tunnel. I also installed a bracket from the plate to the I beam of the suspension to eliminate any flex.

I'll cover the entire installation in a future issue of Excellence with the project car (at Pete's discretion) but here are a few pictures to show the method I used. The "feel" and modulation of the clutch is dramatically improved. Absolutely smooth as silk now.

[skeates]

I'm curious how the clutch pedal was modified for a return spring? It looks like the stock return spring is disconnected (makes sense since it would be pulling the clutch pedal to engage the clutch) and another spring added onto the clutch pedal. With the hydraulic set-up how important is a clutch return spring?

[PRS914-6]

I'm curious how the clutch pedal was modified for a return spring? It looks like the stock return spring is disconnected (makes sense since it would be pulling the clutch pedal to engage the clutch) and another spring added onto the clutch pedal. With the hydraulic set-up how important is a clutch return spring?

The pic was taken during the prototype process and the spring was ultimately removed. You don't want downward pressure with a hydraulic system. The stock spring pushes down and is NOT a return spring. Like brakes, you want the master cylinder piston to completely retract allowing the internal port to be exposed at rest.

On my 915, there is enough spring to push everything back properly.

As a side note......if you do this system, make sure the push-rod you make that is attached to the pedal has a small amount of clearance between the rod and the master cylinder piston at rest (again to keep the internal port open)

[skeates]

I'm curious how the clutch pedal was modified for a return spring? It looks like the stock return spring is disconnected (makes sense since it would be pulling the clutch pedal to engage the clutch) and another spring added onto the clutch pedal. With the hydraulic set-up how important is a clutch return spring?

The pic was taken during the prototype process and the spring was ultimately removed. You don't want downward pressure with a hydraulic system. The stock spring pushes down and is NOT a return spring. Like brakes, you want the master cylinder piston to completely retract allowing the internal port to be exposed at rest.

On my 915, there is enough spring to push everything back properly.

As a side note......if you do this system, make sure the push-rod you make that is attached to the pedal has a small amount of clearance between the rod and the master cylinder piston at rest (again to keep the internal port open)

Thanks for the response! You are correct - the stock clutch pedal spring adds some pre-load to the clutch cable and I can certainly understand why it would be removed for the hydraulic set-up. I had "return spring" in my head at the time and used it without thinking.

It sounds like with the 915 transmission one can get away with not adding a return spring to the clutch pedal when doing this conversion. I'm planning on using a Subaru transmission in my project and haven't seen much detail in the suby conversion threads on this subject. I noticed that in the original pictures (at the start of the thread) a return spring had been added to the clutch in the background so I thought I'd ask the question. BTW Great set-up PRS914-6!