[tom s]

It chattered a lot when taking off from a light.Never tried to race it,might have been good.Tom

[HWYSTR455]

Just because someone doesn't experience the issue doesn't mean it doesn't exist.

Here's a good read:

https://www.motortrend.com/features/...982-1234-55-1/

Excerpt:

"Diaphragm: This design has been around for the last 20 years, mainly on GM cars. Its chief advantages are low pedal pressures (so there's no linkage or firewall flex) and quick, even engagement/disengagement. Unlike the other two designs that utilize coil springs, a diaphragm clutch has a single spring with multiple fingers, called a Belleville spring. Since the Belleville spring can't go into coil bind, it tends to overcenter when engine rpm exceeds 6000. Once created, this condition persists during disengagement, due to centrifugal force, resulting in the pedal sticking to the floor, especially with stock-type OEM units with flat fingers parallel to the outer casting. Certain high-performance factory units and virtually all aftermarket pieces use a longer spring with the fingers arranged in a cone shape that protrudes outward and up in relation to the outer casting, which significantly delays the onset of the "overcenter'' condition. With these designs, a shorter-thanstock throwout bearing is usually required."

Some call the phenomenon 'Pedal sticks to the floor', I call it 'hanging'.

As for 'cone' fingers, another excerpt:

"With these types of fixes, the diaphragm makes a good heavy-duty street/strip clutch. However, it must be recognized that they are really only a "Band-Aid" approach. "

I will add that the more the fingers are raised, the less life the PP has. Many D-PPs have raised fingers, some are completely flat, and yet others can even be 'coned' inward.

As a D-PP becomes 'compromised', the RPM that it hangs at progressively gets lower. I recall having cheap clutch setups that would hang, and I would continue to drive them until I had the time/money to replace them. So I've personally experienced it. Many times.

I became a pro on bench-pressing munchies because of clutches, and have replaced them over back to back weekends several times.

Adjustment is critical on all clutches, but is has little to no effect on hanging.


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[Formulajones]

I never said I haven't experienced it but I have cured the issue with proper adjustment. As far as cheap clutches go ya get what ya pay for

[HWYSTR455]

Several have commented they haven't experienced it, I wasn't targeting anyone.

I know people with modern muscle that wind their' engines pretty high, 7k+ ranges, and have had issues. Those who switched to the SPEC stuff have been happy with them in those cases.

I've seen even mainstream 'performance' clutches suffer, it's not always the cheap ones that have issues.

I used to use some of the higher end Hayes stuff and have exploded discs. Pretty sure I posted pics of one of those. And that was on street tires, on the street.

One thing I've shared in the past also is the Speed Direct linkage upgrade kits, even a daily driver could benefit from:

https://www.speeddirect.com/shop?search=linkage&order=



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[i82much]

I never had a clutch hang on me, I just had pieces of the disc and springs floating around in my bellhousing and some really loud noises. Once every few months until I couldn't afford to drive like that anymore!!

[HWYSTR455]

Here's the pic, found it. Pretty sure it's a Hayes. Hung it on the wall for a conversation piece.



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[AG]

I've had that happen several times with cheap parts store replacements with a 400 Hp motor.

[scott70]

Originally Posted by HWYSTR455

Here's the pic, found it. Pretty sure it's a Hayes. Hung it on the wall for a conversation piece.



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The specs have a 11.75” disc and Kevlar? The 2 and the 2+. Also do people consider the McLeod to be a cheap clutch? The 221 or the 321.

[Skip Fix]

"became a pro on bench-pressing munchies because of clutches" I was, then I tried that on my iron case 4 speed in my college 69 Roadrunner! Dang it was heavy!

[TheSilverBuick]

I like the Zoom on my Buick 455/TKO-600. 3800lb car, 6,000rpm shifts, mid-12's. Good pedal feel and holding up.

[tom s]

My clutches help me get my range of motion and strength on the total knee replacement I got last September!Tom

[GtoFM]

Originally Posted by HWYSTR455

One thing I've shared in the past also is the Speed Direct linkage upgrade kits, even a daily driver could benefit from:

https://www.speeddirect.com/shop?search=linkage&order=

Following because I've bench pressed a few Muncies in my youth, but at 70 I don't plan to try it again, so I want to get it right the next time! I looked into Speed Direct, but they don't offer Pontiac A-body ('64) linkage. HWYSTR455, did you have custom linkage made?

[HWYSTR455]

Originally Posted by scott70

The specs have a 11.75” disc and Kevlar? The 2 and the 2+. Also do people consider the McLeod to be a cheap clutch? The 221 or the 321.

Funny, I've used the 'spec my car' wizard and it's provided me a couple diff outputs. I would have to say call them to be sure.

The Stage 2+ is Carbon/Semi-Metallic/Kevlar, think the regular Stage 2 is straight Kevlar.

I saw some that showed 26 spline, and some 10, when I used the same car, so I think I'm going to order a catalog.

They make everything in-house, and can make whatever you want/need.

Funny thing about disc sizes, some manufacturers actually make larger discs & PPs that fit 10.5 bolt patterns. McLeod is one of those manufacturers too by the way. I think they made like a 10.95 disc/PP that fit a 10.5 pattern. I've used some of those before.

I don't think McLeod is a 'cheap' clutch, they were my go-to for years, but, you have to know what to order. I've had issues with talking to sales people there, some tech people too, just picking standard stuff out of the catalog. I recall some of the 'kits' also didn't come with the proper TOs, which is frustrating. And at one point, their' diaphragm PPs were not very good. They for the longest time catered to a more race customer, but believe that has changed.



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[HWYSTR455]

Originally Posted by GtoFM

Following because I've bench pressed a few Muncies in my youth, but at 70 I don't plan to try it again, so I want to get it right the next time! I looked into Speed Direct, but they don't offer Pontiac A-body ('64) linkage. HWYSTR455, did you have custom linkage made?

Yeah, just use the 64-67 Chevelle big block kit:

https://www.speeddirect.com/shop/pro...=linkage#attr=

You can call and ask specifically if you'd like. As I recall they are very helpful.

Speedway carries them too, might get a better deal than going direct.

The kit I got was for a 2nd gen bird, and ordered the 70-81 camaro one, fits and works great. I ordered one for a 71 GTO I used to have too, it fit and worked great, but never drove that car with it installed. (Sold it)


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[Lemans64]

Got talked into a RXT Mcleod dual disc, in my 64, does it slip, not a chance, but not quite the street clutch either.
Chatters, and when first put in it was rather grabby, either off or on. Does not have a sprung hub in either so transmits
Engine load thru disc, vibrates or makes noise at certain low rpm. Would not use this clutch again for street use.
Call was made to Mcleod and this was they suggested due to weight to HP, & gear ratio. Too much clutch and hard to get used to.

[scott70]

Originally Posted by Lemans64

Got talked into a RXT Mcleod dual disc, in my 64, does it slip, not a chance, but not quite the street clutch either.
Chatters, and when first put in it was rather grabby, either off or on. Does not have a sprung hub in either so transmits
Engine load thru disc, vibrates or makes noise at certain low rpm. Would not use this clutch again for street use.
Call was made to Mcleod and this was they suggested due to weight to HP, & gear ratio. Too much clutch and hard to get used to.

yes looking at any of the dual discs looked like overkill for what Im doing and are pricey. I think Im going with the mcleod 221. Its got to be at least as good and hopefully better as the centerforce ll Ive been using for years and had no problems with. I never knew people had problems with the centerforce weights which Im sure is rare but now hearing it it has kind of steered me away from them at the moment. Going to order the mcleod steel flywheel 462101 too ,,,,hopefully its dimensions are close to the OEM flywheel Im still using as I have read there are some manufacturers where the diameter isnt the same or the thickness.

[Formulajones]

Ive never in my 30 something years of using centerforce ever had or seen any issue with the weights.

Could it happen? Maybe? But the chance is so minimal in my experience it ranks right up there with having a possible issue with any clutch you pick so it really doesn't matter.

You said yourself youve never had a problem either. Sometimes I think people get too paranoid when one person says something negative about a product.

I'm sure you'll have success no matter what clutch you choose.

[HWYSTR455]

Originally Posted by Lemans64

Got talked into a RXT Mcleod dual disc, in my 64, does it slip, not a chance, but not quite the street clutch either.
Chatters, and when first put in it was rather grabby, either off or on. Does not have a sprung hub in either so transmits
Engine load thru disc, vibrates or makes noise at certain low rpm. Would not use this clutch again for street use.
Call was made to Mcleod and this was they suggested due to weight to HP, & gear ratio. Too much clutch and hard to get used to.

Yes, many have complained about the on/off of the RXT, and think the RST is a better choice, but have heard some found them to slip in high torque apps. Dang they are not cheap. And add a certain level of complexity. Not a lot, and like with any clutch install, one needs to take care to do it properly.

True it's possible to knee-jerk by reading reviews/experiences, and you don't know all the circumstances. Like if there was installation error(s) or not. Generally, people tend to blame the product and not their' own errors.

I have seen the weights hung up, and know the people who installed them who were not 'incompetent'. It happens for real.

I've seen pics of the weights retaining ring come apart too. Some of the failures I saw were due to rust on the fingers, not sure if it was from being close to the sea or what, but believe it was due to salty air/rust. Also have heard about vibrations, and sometimes a few cycling of the pedal/PP corrects it.

I dunno 100% they have actual legitimate issues but have heard enough to think there are some, even if only 10% of the complaints are valid. Personally, I thing the weights are a gimmick, and with a quality traditional setup you would be just as well or better off with less to go wrong.



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[scott70]

Yeah I tend to over research stuff,,maybe because theres been too many times where I did no research and got burned. I had a feeling asking about clutch choice would be a loaded question but I tried it anyways. Ive read about almost every clutch manufacturer and materials used,etc on the internet and for every 10 good stories you here there are also bad ones that sound like they have some legitimicy Just when I made up my mind I would read something negative and would change my mind. Yeah I personally havent had any issues with my centerforce for a good 20 years. I think Im going with that mcleod,,,It sounds like a good clutch overall,,,the 221 doesnt sound like some race version I wouldnt be happy with on the street but can handle some abuse and isnt a POS. If it doesnt work out over the next few years I can always take it out and try something else. Im getting older and crawling under these cars and wrestling with heavy parts isnt as fun as it used to be. The new tkx,clutch,etc will all be installed without a lift. Just put the car up on stands as high as I can get and Ive got a knowledgable,younger neighbor thats willing to help. Hes the one that did all the body work on the gto a few years ago and has a 7 sec 1300 hp 55 chevy.
I will be taking the flywheel and clutch kit to the machine shop and check for balancing before install.

[HWYSTR455]

As an update, SPEC did respond to an email inquiry regarding a catalog. Unfortunately, it's an Excel spreadsheet. Uhg.

Some listings to include disc spline count and other notes, but no info on disc diameters or fitment info, it's just by application.

I emailed them back to see if there's a way to provide notes and/or if there a dash-codes for ordering, waiting to hear back.

Obviously, if you call, they will give you the required info and form an order to your requirements, but was hoping it would be in a typical glossy catalog form.


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