[HALFWAY]

I am replacing a 64-326 with a 65-326 and I am installing the manual transmission from the 64 onto the 65. I purchased a new pressure plate and clutch plate. Once I removed the pressure plate from the 64 I realized the two did not look the same. Pictures included.

The old one has 3 fingers and the new one has a dozen or so fingers.

Will this setup work and the important distance where the fingers line up?

The new part is a LUK and all the pressure plates I have searched for looks like the new one.

Do I have something weird or old design no longer used?

Also, the old motor has a ball bearing insert for the transmission shaft and the new kit has a solid bearing, should I use or get a new ball bearing insert versus the sold bearing insert?

Thanks

[John V.]

No expertise here but the original '64 GTO used a Belleville style diaphragm type pressure plate. It was something I remember was always mentioned as a technical "feature", something to oooh and ahhh over, like the fact it had a Hurst shifter.

Pretty sure same type was used for all Tempest applications, different dia. and/or spring pressure used. I remember the original pressure plate was very "stiff" in my GTO even with 18 yo legs. While I was away at college, my sister had the clutch replaced and I was very bummed when I came home to discover how feather-light it felt. Never thought that clutch was as good as the original because it took so much less pedal pressure to release.

The Belleville style is what your new one is.

The 3 finger style is called a Borg & Beck style. It is similar to a Long style which is for drag race applications because of adjustability from what I read, you wouldn't use a Long style on the street. A Borg & Beck can be (not always) designed to increase clamping action under high rpm to reduce slippage.

Each has its merits I guess.

But the original behind your 326 would have been the Belleville style AFAIK, in '64 or '65.

I'm not familiar with LuK as a brand, but then I wouldn't know one brand from the next, haven't bought a new clutch in decades.

[John V.]

Forgot to say, assuming the clutch is correct for your application, I suspect either uses the same throw-out bearing. I figure any minor dimensional difference between clutches would be taken up with the clutch rod adjustment. So you should be good to go.

You might find the new one will feel different than the old when pushing on the clutch pedal, similar to the difference I felt 40+ years ago when the clutch was swapped but I figure nothing really to do with the B&B vs. Belleville basic PP design, more to do with how "stiff" the manufacturer designed your particular units to be. The diaphragm style does have an "over-center" effect inherent in the design, which has the effect of reducing pedal effort when the pedal is depressed, say as you sit at a light with the clutch pedal fully depressed. This is one of the merits of its design.

[tom s]

John,they use diff length TOB.Tom

[John V.]

Tom, thanks for the correction. Always learning something new!

[johnta1]

The diaphragm type was easier to hold the clutch in like at a stop sign/light.
The holding ability was acceptable.

The B&B type generally needed a he-man leg to hold the clutch in if it was a HD type.
The holding ability was greatly enhanced.
(no slipping when running, good for racing)



The other not sure about seemed to be a Ford thing.

[HALFWAY]

OK glad to know what I have.

I will have to say the pressure it took to depress the clutch was hard and at 58 I will most likely appreciate the lighter pressure.

The kit came with the a brass insert for the crankshaft side and the original one has a ball bearing setup, the 65 motor already has an insert but it is not brass.

Do I have to remove the non-brass insert to use the brass one or maybe the ball bearing style?

If I have to remove it what would be the best way?

[tom s]

WOW,im 72 going on 73 and still use the B&Bs!Tom

[HALFWAY]

Originally Posted by tom s

WOW,im 72 going on 73 and still use the B&Bs!Tom

I got chicken legs, lol. Also for the wife's benefit.

[johnta1]

Of course Tom didn't mention his left leg is 3 times bigger than the right.

[HALFWAY]

OK I have the pilot bushing out, rented a puller.

Should I use the bearing or brass bushing?

Seems the bearing would be less wear, friction and seizing.

Thoughts?

[gtospieg]

I use the bearing...no problems

[John V.]

I'd like to hear what the experts say.

The '66 MPC shows p/n 907321 for all '57-'66 man trans applications except for the '64-'66 6 cyl Tempest.

It used p/n 3752487 which is a Chevy p/n, no surprise since at least the '64/'65 Tempest 6 cyl was essentially a Chevy engine.

The PMD MPC gives no further descriptive info except to say both p/ns are Crankshaft Clutch Pilot Bearings.

But the Chevy Oct. '62 MPC is helpful.

It lists the 3752487 and describes it as Bushing Type, 19/32" ID x 1-3/32" OD x 3/4".

Applications show '39-'63 ALL including Corvette except auto trans.

It lists the applications for 907321 as '38-'39 ALL except CC & DC, I'm not sure what models are represented by CC or DC.

But the description says "ND 7109".

ND refers to New Departure, a bearing manufacturer. And ND 7109 would be a single row ball bearing type.

I'd always heard either could be used. Was never sure which type PMD installed in production.

From what the MPC indicates, the ball bearing type would have been O.E.

In 1962, the ball bearing type was 3 times the price of the bushing.

That doesn't necessarily make it better than the bushing.

Seems the bushing is more forgiving of misalignment than a roller bearing. Also, the roller bearing may be more prone to failure which can damage the trans input shaft. The bushing can wear resulting in clutch chatter.

That said, there are apparently different type bushing materials so not sure which type bushing is best. One source says don't use one impregnated with steel. If it sticks to a magnet, it is not good, bronze is preferred, won't stick to a magnet.

From what I read elsewhere there are as many guys that favor the bearings as favor the bushings.

So I'm as curious as you to learn not only which type was used in '64/'65 production (signs point to PMD using the bearing in V8 applications), but also which type the experts here recommend for best performance.

[Tom Vaught]

I had a failure on the bearing type pilot bearing one time, course my shifting technique might have loaded the Pilot Bearing a bit more than a old lady driving the car.

Replaced it with a proper bronze bushing and never had another trans/shifting issue afterwards. When the Pilot Bearing in the crank failed it also wobbled enough to hurt the large input shaft bearing too. Bushings forever for me.

Tom V.

[Old Man Taylor]

My experience is the opposite of Tom Vaught's. My car originally came with a pilot bearing. I had built one engine with a crank that was not machined for a bearing, but I didn't discover it until I was installing the engine. My short term solution was to use a bushing and cut down the outside diameter. It worked fine, but it didn't last long. Since then (1979) I have used nothing but a bearing. I have never had any problem at all from using a bearing. That included power shifting the car at the drags.

[64speed]

I have always used a diaphragm style clutch to replace any borg and beck style I came across. My brother in law just got a luk from rockauto and it seems good. I have also had good luck with zoom brand clutches in performance applications for about half the price of a similar centerforce or mcleod

[tom s]

I have never looked for the cheapest pressure plate,I'm stuck on McLeod and B&Bs and have been using the same one in my 421 Tempest for 20 years now.I hate pulling trans and bell housings !I have been lucky with not having to replace TO or pilot bearings.I have learned that those 2 items you replace when you see them,needed or not.Tom

[rexs73gto]

I've used the bearing in all of my engines since 1971. I tried the bushing in my 69 bird & it went out in just a bit over 1000 miles & I went to the bearing & didn't have to replace it & sold, traded it in on my 73 GTO & it still worked fine. At that time I ran the he!! out of the car on & off the track. I will use nothing but the bearing now. Also because the bearing is that much closer in tolerance you have to be correct on the install or you don't get the trans in. In that regards it also keeps the input shaft on the trans better in line.

[aceaceca]

I would not use an open face bearing. I think it should be a sealed bearing. If you switch from a spring clutch to a diaphragm type clutch, you have to remove the over center spring from under the dash or sometimes outside on the clutch linkage ala 62 Pontiac. This spring helps offset the pedal pressure required on a spring type clutch. The diaphragm clutch uses centrifugal force as it spins to increase clamping power. On my 62 ,I once put a diaphragm clutch in it and was baffled when the pedal went "bam" to the floor and stayed there. Took it back out and put a spring type clutch in as it came from the factory. The 64 GTO came with a diaphragm clutch as did 65.

[Tom Vaught]

Originally Posted by Old Man Taylor

My experience is the opposite of Tom Vaught's. My car originally came with a pilot bearing. I had built one engine with a crank that was not machined for a bearing, but I didn't discover it until I was installing the engine. My short term solution was to use a bushing and cut down the outside diameter. It worked fine, but it didn't last long. Since then (1979) I have used nothing but a bearing. I have never had any problem at all from using a bearing. That included power shifting the car at the drags.

If everyone's experiences were the same what fun would that be.
I think I soured on the bearing as the input shaft was also hurt and that was unexpected $$$ and I knew nothing about Muncie transmissions at the time.

If the trans had not a problem (at the same time) I probably would be running a bearing.

Tom V.