I like the hydraulic for the ease..
I rebuilt my z-bar, but still don't like the feel of it
I want it to feel like a new car
Putting a hydraulic clutch on it won't make it any easier... you're still pushing against a 3,200lb (or greater) static-load pressure plate. To my knowledge, the hydraulic conversions do not have any changed geometry for additional leverage and therefore mechanical advantage.
If you've ever driven a '60s Dodge truck, you know what I'm talking about. A friend had a '67 Dodge pickup, 2WD, with a Slant Six and 3-speed. It had a hydraulic clutch, and it was harder to push than my '73 Challenger.
If you want ease of operation, lose the over-center spring on your clutch pedal and install a diaphragm clutch (GM style)--a complete Centerforce Dual-Friction if you're making a ton of power, but otherwise a pressure plate from a GM 10.5" application will work with your current disc. Ask me how I know.
We sell Sachs clutches, and they offer completely new clutch kits with the diaphragm-style cover, new disc, throwout bearing, pilot bushing, and alignment tool as an option for Mopars.
For anyone considering
any diaphragm-style cover on a RWD Mopar passcar:
you absolutely MUST remove the huge over-center spring under the dash. If you don't the clutch pedal will stay on the floor, if not the first time you push it, then when you least expect it. Nasty surprise on a power shift. Centerforce's instructions tell you this, or at least they did in the past. Sachs' don't.
So, you're reading this and thinking to yourself, "Gee willikers, self! This sounds like a swell upgrade!" Not so fast, Beav... it has its drawbacks, too:
- Significantly-lower clamping load on the diaphragm clutch versus the original Borg & Beck 3-lever design. Generally 600-1000lbs less static load (clamping force at rest).
- Slower engagement, though this really isn't a huge issue unless you're racing.
- Diaphragm clutches tend to hang on the floor on high RPM shifts, even without the over-center spring.
- Diaphragm clutches weigh more... not a huge amount, but it's 100% rotating mass, and a pretty-large diameter one at that.
The Centerforce (actually, Scheifer--I'll get to that) design's centrifugal weights help overcome much of this; the pedal won't hang on the floor and the engagement is accelerated due to the weights' pulling the fingers back out. It does help with the clamping load as well, but not enough to make up 600+ pounds of force. I believe (and this is just a belief of mine; I have no evidence) that this is the reason that Centerforce developed the Dual-Friction design: less clamping load can be offset by more friction. You're still going to have the higher weight, and have you priced a Dual-Friction of late? Yow.
Personally, I've never thought muscle-era Mopar clutches were bad at all, though for pedal feel I vastly prefer the Long-style clutches used in early A-cars and some Slant Sixes (and virtually every muscle-era HP Ford). I also like the Long's centrifugal roller assist, which means lighter static loads than a Borg & Beck but impressive clamping force at RPM. I hated the spongy diaphragm clutch in my '78 Trans Am so much that I switched it out to a Mopar B&B unit.
My ultimate clutch? 10.5" Long-style cover (Ram used to make this in a Mopar bolt pattern, but apparently it's long gone, pardon the pun), Centerforce Dual-Friction disc, stock throwout, and a roller pilot bearing. Expensive unit to piece together, even back when the weird Ram cover was available. You can use a Long 11" pressure plate on a Ram Mopar flywheel, but it has to be the '69-down "true" 11" clutch with the 143-tooth flywheel, not the '70-up 10.95" that bolts to the 130-tooth flywheel... so if you have a factory aluminum bell, you're out on that option.
Now, for a bit of history...
For those not old enough to remember (and I'm one of them), the "revolutionary" Centerforce weighted-diaphragm design was not new when Centerforce formed in the late '70s. Bill Hays started and eventually sold the Hays Clutch dynasty, then started Centerforce Clutch. I don't know exactly how things went down at the patent office, but Carl Scheifer actually invented the Centerforce's centrifugal-weight design in the Sixties, and marketed them under the name "Rev-Loc". Scheifer clutches were popular back in the musclecar era. I don't know if he never patented the design, if he just let the patent expire, or if he sold it, but Bill Hays somehow got ahold of the patent and has kept it solely his since around 1977. So, for your edification, no, Centerforce didn't revolutionize anything.
Scheifer also used to make pressure plates (B&B, Long, and Rev-Loc diaphragm) that were high in aluminum content, with a steel pressure ring. They weighed significantly less than comparable clutches to improve rotating mass and allow for quicker revs. They were at the forefront of aluminum flywheel development as well.
