64-65 Clutch Fork

[Michael H.]

Re: 64-65 Clutch Fork

There's one more piece to the puzzle that no one has mentioned yet. The part is the bracket that bolts to the clutch pedal. This is the part that changes the clutch pedal travel from normal to "fast", depending on it's installed position.

There's more to the story though. A new slightly revised part replaced the original design for some cars during the 65 and 66 model years. This part, and why some cars require it and some don't, should be part of the story.

All 63-66 small block cars used one design while all 65-66 big block cars used a slightly different design. I'll post a pic of both designs later.

Bet a lotta guys are going to run out to the garage tonight to see if they have the correct big block clutch pedal bracket.

[Clem Z.]

Re: 64-65 Clutch Fork

i think there was a story in corvette news how to do this and if i get time i will look and see if i can find it.

[Tom H.]

Re: 64-65 Clutch Fork

Joe- I have an original fork from my SHP block. I'll photo it in detail with graph paper behind and a scale in the image. Can't loan you the original but would be glad to measure trace detail etc. I can also scan it for you

[Joe L.]

Re: 64-65 Clutch Fork

Joe- I have an original fork from my SHP block. I'll photo it in detail with graph paper behind and a scale in the image. Can't loan you the original but would be glad to measure trace detail etc. I can also scan it for you

Tom-----


The more data I can get on this, the better. Detailed photos as you describe would be a great help. I'll send you my e-mail address if you'd like to send them that way.

[Bill M.]

Re: 64-65 Clutch Fork

John,

If you could post that same information for C-1s I believe it would be most appreciated by many. I in particular want to check the degress of separation on the cross shaft on my '61. I have a suspicion that it is from a passenger car.

Thanks,
Mike

Mike:

I measured 137 degrees on my '59. I got 2.35 inches on the short arm and 3.64 inches on the long arm. This part is original. There is a bracket bolted to the long arm for the over-center spring.

Bill

[Tom H.]

Re: 64-65 Clutch Fork

Joe- Please do. I'll clean it up and get the pix to you in week or two.

[Peter L.]

Re: 64-65 Clutch Fork

Guys,
I have a late 63 (SN 119306. build July 10 date), 327/340HP, with a Muncie trans. The bellhousing is correct (3788421), and according to the parts people (Paragon, etc) and what I can glean from the judging manual, it all should be good. The clutch fork is supposedly correct (it matches the photos for what should be in a 63 thru 65, again, same as Paragon part number 1474K). It is the clutch fork I had with the Borg Warner trans/bellhousing that was in the car when i bought it. I swapped both the trans and bellhub for correct ones well before I actually started the restoration process. The problem is that when the fork is assembled to the ball stud in the bellhousing, the centerline of the TO bearing is about 1/2" short of the centerline of the clutch release fingers. Is it possible that when Corvettee changed from the Borg Warner to Munice gearboxes in late 63, they also changed the clutch fork? Any body have any suggestions of what I can do to make this work?

[Joe R.]

Re: 64-65 Clutch Fork

Joe L.,

Would be glad to send you a 64 fork. Send me your address via PM. It's not necessary to send it back.

Just share the information you gain from the part!

Thanks,

JR

[Joe L.]

Re: 64-65 Clutch Fork

Joe L.,

Would be glad to send you a 64 fork. Send me your address via PM. It's not necessary to send it back.

Just share the information you gain from the part!

Thanks,

JR

JR-----


Thanks for the offer. However, I did obtain a 64-65 fork for inspection. I'm sure I posted a report on what I found but, apparently, I must have done it in another thread. Anyway, the 64-65 and 66-81 forks are functionally interchangeable. The difference relates to subtle changes in the configuration of the two and the 64-65 is fabricated from slightly thicker material. I'll post some pictures here:


DSCN1102.jpgDSCN1103.jpgDSCN1105.jpgDSCN1106.jpg

[Joe L.]

Re: 64-65 Clutch Fork

Guys,
I have a late 63 (SN 119306. build July 10 date), 327/340HP, with a Muncie trans. The bellhousing is correct (3788421), and according to the parts people (Paragon, etc) and what I can glean from the judging manual, it all should be good. The clutch fork is supposedly correct (it matches the photos for what should be in a 63 thru 65, again, same as Paragon part number 1474K). It is the clutch fork I had with the Borg Warner trans/bellhousing that was in the car when i bought it. I swapped both the trans and bellhub for correct ones well before I actually started the restoration process. The problem is that when the fork is assembled to the ball stud in the bellhousing, the centerline of the TO bearing is about 1/2" short of the centerline of the clutch release fingers. Is it possible that when Corvettee changed from the Borg Warner to Munice gearboxes in late 63, they also changed the clutch fork? Any body have any suggestions of what I can do to make this work?

Peter----

I do not understand the reason for your problem unless the Paragon reproduction is "off" in some way (which I doubt). The 1963 clutch fork was unique to that year. It uses a "ball-and-socket" type interface between the fork and the fork push rod. The 64+ uses an "eye-and-clevis pin".

[Joe R.]

Re: 64-65 Clutch Fork

JR-----


Thanks for the offer. However, I did obtain a 64-65 fork for inspection. I'm sure I posted a report on what I found but, apparently, I must have done it in another thread. Anyway, the 64-65 and 66-81 forks are functionally interchangeable. The difference relates to subtle changes in the configuration of the two and the 64-65 is fabricated from slightly thicker material. I'll post some pictures here:


[ATTACH=CONFIG]43765[/ATTACH][ATTACH=CONFIG]43766[/ATTACH][ATTACH=CONFIG]43767[/ATTACH][ATTACH=CONFIG]43768[/ATTACH]

Joe L,

Apparently I am responding to a thread that was started in 2008! Gettin old and not lookin at what is going on anymore!

Thanks for the info.

JR

[Peter L.]

Re: 64-65 Clutch Fork

Guys,
I just spoke to Paragon, and they set me straight. First, this is the first time I've ever done this, so my ignorance is epic. After talking to Paragon, I was told that the TO bearing does not bottom out in the clutch fork, but in fact rides about a 1/2 inch out from the bottom of the fork. So I did a quick check by mounting the clutch fork to the ball in the bellhousing, and when I visually center the TO bearing in the pilot hole, on the clutch fork, it is about 1/2 inch out from the bottom of the fork. I will be assembling it on to the engine and the trans to it in the next week or so, and will let you all know how that goes.
Sorry for the confusion I caused. You people on the discussion boards are amazing in the help and insight you offer. You are the best.
Thanks,
Pete Loscalzo

[David L.]

Re: 64-65 Clutch Fork

JR-----


Thanks for the offer. However, I did obtain a 64-65 fork for inspection. I'm sure I posted a report on what I found but, apparently, I must have done it in another thread. Anyway, the 64-65 and 66-81 forks are functionally interchangeable. The difference relates to subtle changes in the configuration of the two and the 64-65 is fabricated from slightly thicker material. I'll post some pictures here:


[ATTACH=CONFIG]43765[/ATTACH][ATTACH=CONFIG]43766[/ATTACH][ATTACH=CONFIG]43767[/ATTACH][ATTACH=CONFIG]43768[/ATTACH]

Joe,

I have compared my original clutch fork (Feb. 1966 body build date) with your photos of your 3844493 (64-E66) and 3887177 (L66-81) clutch forks and really can not tell which clutch fork that I have. The change from the 3844493 to the 3887177 took place sometime during the 1966 production. It's interesting that my 1966 Chev. Parts Catalog (Oct. 1965) lists the 3844493 fork for the 1966 Corvette 427 w/SHP while the 3887177 is listed for the 1966 Corvette 427 wo/SHP.

In the thread that you started on Nov. 29, 2008 entitled "64-E66 Versus L66-81 Clutch Fork" you state that the metal thickness of the 3844493 fork measures 0.177" and the 3887177 measures 0.157". I measured my fork at several different locations and I get an average measurement of 0.165". I also compared my "U"-shaped spring to your two "U"-shaped springs and really can not see any differences. Enclosed are some photos.

BTW, the metal thickness of my NOS 3892632 and used 3892632 clutch forks (1967-1972 Camaro & others) measures about 0.140" on average. The metal thickness on my used 9787069 clutch fork (1967-1972 GTO & others) measures about 0.157 on average. I also have a NOS 12385352 clutch fork that has a metal thickness of 0.177" on average.

Dave

[Doug L.]

Re: 64-65 Clutch Fork

Hi Joe,
My Dec 13, 1963, 1964 MY has the original transmission (VIN stamped on the tranny flange). The bellhousing has the correct part number and the linkage appears to be correct. Is all orignal? Don't know but I have no reason to think it isn't. The engine has been apart and being reassembled tomorrow. I can take photos and dimensions for you if that will help, but I can't send the clutch release fork. Kissimmee is coming up fast and I can't have it judged without a working clutch.
Doug

[Joe L.]

Re: 64-65 Clutch Fork

Hi Joe,
My Dec 13, 1963, 1964 MY has the original transmission (VIN stamped on the tranny flange). The bellhousing has the correct part number and the linkage appears to be correct. Is all orignal? Don't know but I have no reason to think it isn't. The engine has been apart and being reassembled tomorrow. I can take photos and dimensions for you if that will help, but I can't send the clutch release fork. Kissimmee is coming up fast and I can't have it judged without a working clutch.
Doug

Doug------

Thanks for the offer. However, this was an old thread that got "resurrected". I obtained a 1964 clutch fork years ago and reported on the differences between 64-E66 and L66-81 in another thread which Dave L. referenced above. I also included "excerpted" photos from that post in this post, above.