THOSE USING HYDRAULIC THROWOUT

MIKESPOLARA

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Is the pedal effort any less compared to a normal clutch/throwout bearing. Lets say compared to the easier to push diaphragm pressure plate or is the pedal effort still related to the pressure plate used?
 

rmchrgr

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You don't need an overcenter spring if that tells you anything. I think it might also be a little smoother/linear if that makes sense? I love mine, it's been good. I'm using it with a basic McLeod diaphragm street clutch.
 

Kern Dog

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I have driven a few 4 speed cars with old style linkage but just one old car with a hydraulic clutch...My own.

https://www.forbbodiesonly.com/mopa...-5-speed-conversion-in-a-1970-charger.209725/

My clutch feels like a newer car. The tension on the pedal is smooth and linear.
I had a RAM clutch in a Duster. It had a bit of free play at the first 2 inches of pedal travel, got stiffer through the range of travel, then past the point of release, it got real easy. It wasn't bad but compared to how my Charger clutch feels, the old style was not as easy or as comfortable to drive.
 

Mike67

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They are nice, there is no break over point to overcome. As Kern & rmcharger said its very linear in applied pressure needed.
 

moparedtn

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Diaphragm clutches are easier on your knee than B&B types - that's their claim to fame,
their selling point. More bite from less pedal effort...
Same sort of deal with hydraulic linkage vs. stock type mechanical - less effort for the
same work done, which supposedly justifies the added cost and fabrication required.

Me, I still prefer the old B&B type. I like feeling the actual mechanical workings of a clutch
under my foot ('course, I grew up with clutches in vehicles from the 30's on up thanks
to Pop).
Despite my own "left knee of mush" (docs have been trying to get me to get it replaced
the last 40+ years now!), I still am most comfortable with the stock arrangement of clutch
because I like feeling it working.
Helps monitor the situation, as it were.

Now, my absolutely favorite clutch setup I've ever driven? The one in my old '89 5.0 Mustang.
That one was diaphragm, but with cable-driven linkage on the pedal, complete with self-adjuster.
It gave me the best of both worlds IMO - you still felt the workings of the clutch to an extent,
while also having easier operation of it as the cable did its' thing to soften the working of it.
 

Mike67

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Is it easier? as in having a bad knee
I think they are, we installed one on the Nova and its smooth and pretty easy, considering its basically the same as a hydraulic brake system. The only thing you are really having to overcome is the pedal return spring.
The face of the bearing is almost in contact with the fingers on the pressure plate; I think the McCleod we used said .150-.200" of clearance was required. Instead of having to overcome the pressure of the fingers with a lever (clutch pedal/fork) you get a mechnical advantage of a hydraulic ( high pressure) sytem.
 

rmchrgr

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Is it easier? as in having a bad knee

Depends on what you’re used to and which type of clutch you have but to answer your question, it feels easier.

Hard to say that there is any less actual pedal effort but the fact that it’s smoother through the entire range of motion makes it feel that way. There is no point in the pedal travel where it feels like you have to push slightly harder to get the clutch to release.

There is less free play because like brakes the hydraulic pressure keeps it “primed” so to speak meaning there is less distance for the object being moved to travel. The bearing is essentially in constant contact with the fingers. The amount of free play is probably the main difference between the two types.

When I set mine up I thought the bearing should retract completely from the fingers when released but it doesn’t. I called American Powertrain to make sure I didn’t screw it up and the guy on the phone said it’s not supposed to retract enough where there is a visible gap, it’s a hydraulic piston it does not move very far. If you think about it like a brake system you’ll get a clearer idea of what it’s like.
 
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