Diaphram VS 3 finger pressure plate?

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F&J

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I was reading the old post on clutch pedal problems. I put a new clutch kit in a 69 340 dart with the diaphram plate. That's the only clutch kit I could find that week around here, and I needed to get the car going.

I've always hated the feel of a diaphram in any make of car, and this one is even more horrible as far as feel & operation. It seems to start to grab just as the overcenter spring starts to go "over-center", which just plain makes it a crummy setup to get used to. I also greased all the moving pivots & linkage & bushings...it's no better.

What are you guys running on a stock car that's just for pleasure driving? Should I just spend more $$$ and toss the new plate and get a finger plate?
 
3 finger is a better performance type clutch. But the hot setup is a long style clutch. It is a 3 finger design but has weights that make it even stiffer with higher rpms. Allows for a good pedal feel but not to stiff at low speeds and adle , but firm grab under high loads.

There are many other aftermarket and custom clutchs too. But the 3 finger and the long have worked the best on the street for me.
 
I have a 10.95 inch MoPar Scallop clutch in my 65 Barracuda it’s also a Borg & Beck style (three finger clutch) clutch. It’s a little hard to adapt to an early A body but should work fine in yours.
 
I myself prefer the diaphragms over the 3 finger, probably a carry over thing from my GM days (GM uses mostly diaphragms). I just did a /6 to V8 conversion this weekend on my Duster. The /6 had the 3 finger in it and the pedal would not return all of the way but the clutch worked fine. With the V8 I put in a diaphragm and now the pedal returns all the way and everything works great. The thing I don't like is the pedal is very soft to push in. This would be great in bumper to bumper traffic but I like a firmer pedal. I am going to remove the over-center spring from the pedal so it will stiffen up the "feel". This might help your not liking the "feel" of your clutch also. The over-center spring is in there to make the clutch easier to push.


Chuck
 
I already tried running it without the spring, and it's way too stiff to enjoy driving the car, even just around the driveway. It's a heavier car being a convertible, plus a 3.23, so you need to float it a little. 1st gear seems a little too high; as in it feels more like a 2.something rear end gear when trying to move.

Maybe I'm too fussy, but it just doesn't feel great. To me, it almost feels like the pressure plate itself, has an over-center "spot", and that comes in around the same point that the O/C spring does too. I don't have it registered yet, so maybe I'll just put some miles on it later. I've heard that on some foreign cars with a new replacement diaphram, that they need some miles put on to make them feel better?

I did want to hear from anyone using the diaphram to see what they think about the feel.
 
Thanks for the tip on the clutch pedal being too stiff without the spring. I really didn't want to remove it let alone try and put it back in if I didn't like it. I could see how with a 3.23 and a 2.66 first gear how it could take a little pedal work to get the car rolling. Mine has, for now the 3.23 and a 3.09 first and it even takes a little pedal work to get going. This will be only temporary though because 3.91 are going in the car.

I do know exactly how you feel on the clutch, mine is the same, just as the clutch starts to engage the pedal seems like it tries to help you so you have to change the pressure on your foot to compensate for the change in pedal effort.

Chuck
 
F&J

I'm running a Centerforce diaphram clutch in my Dart and I had to remove the overcenter spring. My pedal feels great and releases just as it should with no binding or any other issues. If you leave the overcenter spring in it has a tendency to overcome the pressure plate springs and keep the pedal from returning nice and smooth as it should. There is also the risk of the pedal staying on the floor when speed or power shifting with the overcenter spring left in.

My 2 cents
 
I don't like the Scallop clutch for everyday driving especially in traffic it takes a lot of force compared to the diaphragm clutch I had when I first converted to a 10.5 inch flywheel but I don’t usually commute in it either. I hated the pedal sticking to the floor and I could never get it to stop completely no matter how many extra springs I added.
 
Thanks for all the input so far, and knowing that some of you take the spring off.

I think these are the only cars out there with a O/C spring, so if a GM or whatever can be designed without one, should I try to change the ratio a little on the clutch linkage to be able to get a softer pedal ?

I've hand built clutch & brake linkages before on rods, and I am aware that you can only change the ratio so much before loosing enough stroke distance on the fork......but this all has me thinking that this "could" be a good idea.

I really didn't want to remove it let alone try and put it back in if I didn't like it.
Click to expand...

I started off struggling with the spring too but then realized that by sliding the pedal shaft out enough to "miss" the pedal stop, that the pedal can swing up way more to easily remove/install the spring.

I could see how with a 3.23 and a 2.66 first gear how it could take a little pedal work to get the car rolling. Mine has, for now the 3.23 and a 3.09 first and it even takes a little pedal work to get going.
Click to expand...

I wondered if there were different first gear ratios...Our dart is supposed to have the original trans...is there a way to look at the fender tag or build sheet to see what it has? I think the tag just gave the trans type.
 
F&J said:
I started off struggling with the spring too but then realized that by sliding the pedal shaft out enough to "miss" the pedal stop, that the pedal can swing up way more to easily remove/install the spring.
Click to expand...

Thanks for the tip I think I will give it a try to see if I like it better without the spring.

[/QUOTE]

I wondered if there were different first gear ratios...Our dart is supposed to have the original trans...is there a way to look at the fender tag or build sheet to see what it has? I think the tag just gave the trans type.[/QUOTE]

I know mine has the 3.09 first gear because it is an OD tranny, they had the low first gear. That is why it is not going to bother me in the least to go with the 3.91's, with the OD high gear my overall final drive ratio will be 2.85

Here is a link on the trans ratios
http://www.moparts.com/Tech/Archive/clutch/17.html

Chuck
 
hi,mcleod clutches makes a B&B/ long pressure plate. it fits where a B&B goes, has the long style fingers, for better ratio, and less pedal effort.
also, you can add c/w to fingers. for street driving use the series 200 disc or serious use, the 300 series disc.lowest base pressure would be in range of 2000#. depending on gear ratio. I have used this clutch combo in a 340 stocker for years. with no clutch problems or breakage.
 
i hate my diaphram pressure plate. i removed the spring and lubed everything and but new bushings in and it still sucks. i hate if for the street. it's ok for racing but i still prefer the 3 finger setup for racing and street use. it's hard to slip the clutch for racing too on the launch. i just don't like that spot in the clutch pedal that you are talking about. i wish i never switched.
just my opinion. everyone is different. i'd rather have a nice smooth travel in the pedal.
 
I my self have had bad luck with the 3 finger type. I guess I'm not that picky. I only have a stock style diaphram style for a big block 409[I think]AMC 10 1/2".Many hole shots and beatings later its still working fine.
 
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