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I installed a McLeod hydraulic T/O bearing a while ago, and found it lowered my pedal pressure by a significant amount, when combined with a 5/8" CNC clutch M/C. I bought it all from Dennis Quella and he'd probably be a good person for you to speak with regarding different clutch packages and their respective pedal pressures.

If you're looking for a very light clutch pedal, this topic describes the installation of a power clutch set-up in a Pantera.
Diaphram clutches also tend to be lighter then the stock, Long, 3 finger style.
I have the effort reduction kit with the Centerforce dual friction clutch. It is a diaphram design.
I wouldn't call the pedal light but I have driven a lot worse. I would take a guess and say it is about 50% of what it would be stock.
This set up with the hydraulic throwout bearing is probably as light as you can make it.
It may also be possible to play with the diameter of the piston in the clutch cylinder to alter the output pressure.
You are going to need to go to someone like Quella to help you on this though.
He may have a few tricks up his sleeves?
I remember Hall putting an automatic trans axle in a Pantera for a guy years ago.
I'm told there were issues with the durability of the unit though. I think it was a Renault transaxle.
Gary did so much custom stuff back when, he took a lot of the knowledge with him unfortunately.
Wilkinson may also be able to help on this issue also. Call him too.
I can vouch for the Centerforce Dual Friction clutch and hydraulic throwout actuator, as well. I have both in my car in addition to a Wilwood master, roughly the same diameter as stock. The hydraulic throwout should remove friction and improves efficiency over the rolling/sliding contact and geometry of the stock throwout lever. Perhaps additional ease can be gained by decreasing the master diameter, although with increased pedal travel.

The hydraulic throwout has the drawback that servicing it means pulling the transaxle, which I had to do just a couple weeks ago to replace the seals (due to my own mistake in adjustment).
Be careful when using a Centerforce pressure plate with a McLeod hydraulic T/O bearing. I have no first-hand knowledge of any incompatability between the two, however; Dennis Quella told me he's seen instances of the Centerforce's counter-weights coming into contact with the McLeod T/O bearing. Dennis said, if you are using a Centerforce pressure plate with a hydraulic T/O bearing, his advice is to remove the counterweights.
Last edited by davidnunn
David,

I agree to ensure compatability, but I believe that the centrifugal counterweights are a feature that reduces pedal effort for a given clutch torque capacity. Removing them may reduce torque capacity at speed; if you don't need the capacity you may want to just use a lighter clutch spring, which would also reduce effort. I recently had my McLeod hydraulic throwout out of my car and it showed no signs of contact with the centrifugal weights.

Another thought to reduce effort is a dual disk clutch, not to be confused with the Centerforce Dual Friction clutch. There is the possibility to have a lighter pedal at the same clutch capacity by increasing the number of friction plates with reduced spring force.
The weights add clamping load as rpm rises. By doing that they also INCREASE pedal effort at rpm.
This in theory permits a lighter stock like load at idle. It may also contribute to the borderline slippage right off of idle that the clutch has.
It also pushes back on the clutch pedal. I have one in my GT350 which uses the ancient mechanical rods and levers and I would say that at 5500rpm the pedal is up an inch.
The slippage at break in really is more likely because of the dual friction materials. Stock-ish on one side and harder then stock on the flywheel side and is like seating a new set of brake pads.
I had a Centerforce dual friction in my
Taurus SHO and because of clearance issues there were no counterweights in that design.
That one wore through the diaphragm fingers in under 10,000 miles.
A ceramic throw out bearing would have been the only option for it. I used the stock throw out bearing since Centerforce never mentioned anything about a throw out bearing compatibility issue initially.
The Taurus design is a self adjusting one with a cable ratcheting design and there is no adjustment possible. The throwout bearing rides on the fingers at a predetermined load. The Centerforce fingers didn't like that. The blackness on them is black paint. Not because of heat treating. That is kind of deceptive by Centerforce if you ask me.
Only after I killed the clutch did I find that people were recommending a ceramic throw out bearing.
I don't have enough miles on the Pantera clutch to know if there is an issue there yet.
The hub used in the clutch disc is also on the fragile side. It breaks easily in installation if you don't line up the input shaft splines right. I broke one of those too.
Bottom line is it has some features but doesn't fix all issues, so buyer beware.
A few notes from a long-time user of annular throwouts, Mr 22. First, they are extremely critical on initial adjustment for free play. More is much better than barely enough. The entire system depends on a single 'quad-seal' that seals hydraulic pressure both at the top (the stationary cylinder) and the bottom (the moving piston). This seal is designed for linear motion only; no rotating motion is tolerated. The engine, bellhousing and ZF all expand a little when hot so setting extra clearance cold works best. If you set too little clearance and things tighten up as it gets hot, the piston will bottom and begin to spin with the clutch and throwout bearing. The seal will then fail in less than 50 miles. Rebuilds are possible but are tricky for the casual owner. Most will be sent back to the mfgr.
Next, all the set-up and adjustment must be done with your 155 lb ZF out of the car and on a bench. Unless you are a body-builder, a shop crane will be your best friend working with this part! If you screw up and need to change anything, out comes the transaxle again.
Mine was installed 18 yrs ago and even though I have had no trouble (after the 1st year), I still carry a second complete assembly on long road trips, since you won't find parts on the road and I hate tow trucks.

On the good side, the system removed 6 lbs of cast iron high-friction parts, and resulted in a light pedal with a stock Long-style clutch and master cylinder. My 5'4" wife has no problem driving the Pantera 8 hrs straight on long trips. Our car also has the stock over-center compound linkage under the dash, which slightly increases the pedal force initally, then drops the foot pressure radically as you push the pedal further down. The annular system is sized such that you get the benefits of a long-throw system built-in, without an increase in clutch pedal load. Finally, the bearing used is a modern constant-contact type, so clutch disengagement is very fast; there is little wasted motion. An annular throwout system also separates the friction disc from the clutch and flywheel nearly twice as far as the stock system. This eases wear on your expensive ZF synchros during shifting.
I honestly belive that you will not find a softer clutch than a mcleod twin disc. I have one on both my Pantera and our Meteor. The one in the meteor is the newer style and I swear you would think the clutch was not actually working properly it is so light. Being it is a dual disc the torque rating is super high as well. I think the smallest one is rated at 800 hp. Having used both the centerforce and the mcleod I can say the mcleod is far lighter.

Sorry to resurrect this thread. I didnt realize till now how long ago this was.
How do you do a dual disc in the Pantera with it's too short of travel slave cylinder?

I was looking at the Lambo Countach and investigating the car, research showed me it is multi disc, about $3500 for the clutch to buy it,you need to disassemble the rear of the car essentially to install it and is only expected to last about 5,000 miles.

I didn't buy the car.
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