Clutches

[Ray C.]

I purchased a replacement clutch for my 63 340HP SWC from NAPA. I have normally used a diaphragm type clutch. I did not order this type of clutch, but it is Borg & Beck type three-finger clutch. My 63 Service Manual shows a picture of a diaphragm type clutch. What are the benefits or shortcomings of the Borg & Beck type clutch?

Thanks for any help!

Ray

[Duke W.]

Re: Clutches

The last time Chevrolet used a three finger coil spring type clutch in a Corvette was 1962, and I believe this also applies to passenger cars.

Diaphragm clutches have been nearly universal since then. They offer lower pedal force for a given amount of clamping force.

Suggest you return it and buy a LUK, diaphragm type. I'm sure NAPA also offers a correct diaphragm type. I have no idea why they sold you what they did.

Duke

[Frank D.]

Re: Clutches

Duke

If it may be of any help to you I just removed the original diaphragm clutch from my '63 340 and replaced it with the Luk diapragm clutch set and is working great. Was initially concerned that the pedal would stick to the floor at high rpm and after numerous " TESTING " of the buzzer tach the clutch is fine. Frank
p.s. love those 097's

[Clem Z.]

NEVER overcenter a diaphragm

pressure plate because it will cause the "sticking to the floor". the way to set the clutch is to jack up the rear of the car,put the trans in gear,have someone try a turn the rear tires as you slowly push in the clutch. when the tires will just turn that is where you want to adjust the clutch pedal so it is against the floor or put in some type of pedal stop so the clutch can not be pushed in any farther or you will over center the pressure plate

[Joe L.]

Re: Clutches

Ray------

I think that someone just sold you the wrong clutch. Period. You probably won't even be able to bolt it up to your 63 flywheel, even if you wanted to use it. If you could bolt it up, it would probably not otherwise work correctly. Likely, you were sold a clutch for a C1 application.

The thing that's strange here is that you were even able to get a 3 finger type unit, at all. I didn't think that anyone, except some of the specialty clutch manufacturers like McLeod or Hayes, were even making these things anymore.

[Duke W.]

Re: NEVER overcenter a diaphragm

Over the years I've heard stories of clutch hangup (won't re-engage after a redline upshift), but with my SWC's clutch linkage set to both "standard" and "fast", I've never experienced it at shift points up to 6500+ or 7200+ on my Cosworth Vega, and I usually keep the freeplay near the minimum specs because I want to be sure that the clutch disengages quickly and surely.

The SWC has a correct OE replacement clutch and the CV clutch is original. Both, of course, are diaphagm type.

Also, I don't use "drag race" shift techniques - just "road race" techniques.

Duke

[Ray C.]

Re: Clutches

Thanks to all for the responses!

Joe, the pressure plate will bolt up just fine, I all ready have it installed. I questioned the application when I tried to engage or check the the through-out bearing by hand. The feel just did not seem wright. Pulled the transmission last night to check and everything was installed OK. Thanks to you, Duke and the other members for all your help. I just called NAPA and they are trying to locate the correct clutch for this application. Because they are willing to take back the Borq type clutch after I installed it I will most likely be using another NAPA clutch.

Again thanks to All!

Ray

[`Michael Southard]

Re: Clutches

Borg & Beck vs Diaphram type??? I just took out my diaphram clutch and it says "Borg & Beck on it????

I though they were two different types of clutches?

[Joe L.]

Re: Clutches

Michael-----

Borg and Beck was a manufacturer of both "3 finger" and diaphragm types of clutches. Many GM clutches, especially the friction discs, were manufactured by Borg and Beck. For some reason, though, the term "Borg and Beck" has come to be synonomous with the "3 finger" type. They were one of the primary sources of the "3 finger" type units and, I believe, they once held the patent on them. However, I'm fairly sure that they made many diaphragm type units, too. Certainly, they made friction discs for both types, if not the complete assemblies.

I think that Borg and Beck has pretty much "contracted" to being a European supplier, now. I think that they have become part of a larger operation, too (maybe, Federal-Mogul).