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Technical Late 60's GM clutch fork question

Discussion in 'The Hokey Ass Message Board' started by Corn Fed, Mar 13, 2018.

  1. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    To gain a little extra clearance in the 4 speed I’m putting in my ‘32 I need a clutch fork that is angled backwards. Most all of the forks I see angle forward, with a few that are straight out.

    In my search, I found a single late 60’s Impala vendor who shows what appears to be what I need. They say it fits 65-69 Impala, Caprice, Bel Air, and Biscayne. But when I look at other 60’s Impala vendors for the same fork, they all show one that goes forward, and they are the stamped variety.

    Does anyone have any experience with one of these year cars to know if the fork shown is actually what was used in them? Sorry for the poor quality pic.

    Or does anyone know of a GM fork that angles back?


    Fork.jpg
     
  2. squirrel
    Joined: Sep 23, 2004
    Posts: 38,972

    squirrel
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    I know a guy with a welder, he could probably make a fork angle back, if you give him an hour.
     
  3. BJR
    Joined: Mar 11, 2005
    Posts: 4,079

    BJR
    Member
    from Minnesota

    Like Squirrel said, cut, bend, weld, done.
     
  4. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    Sure, I could cut and weld up one of the stamped ones I already have. Or I could heat and bend one of the forged straight out truck types. But if there's already a factory designed one out there, I'd just as soon use that.
     
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  5. squirrel
    Joined: Sep 23, 2004
    Posts: 38,972

    squirrel
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    I don't remember any...

    There are a couple different style non-stamped arms used with the trucks, the skinny one from the 50s, and the wider one from the 60s.
     
  6. DDDenny
    Joined: Feb 6, 2015
    Posts: 8,707

    DDDenny
    Member
    from oregon

    Are you having clearance issues due to using original frame/center structure?
    You more than likely won't go to the trouble but thought I'd throw in an option for those that don't know this and may deal with it in the future.
    The 64-67 Nova/Chevy II's used a belhousing that puts the throwout fork at the 7:00 position compared to the 9:00 position on most everything else.
    The 62 and 63 belhousings look the same but have a smaller bearing retainer hole and only a Muncie from late 63 will fit. I've seen them machined out but I don't recommend it.
    Granted, they aren't laying around like the others and can be more money but they sure can be a real problem solver in tight areas.
    They may not pass the "traditional" test but Lakewood sells a scattershield with the 7:00 throwout exit.
     
  7. Rick S
    Joined: Mar 30, 2006
    Posts: 100

    Rick S
    Member

    fork.PNG

    Something like this?
     
  8. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    The fork pictured above is angled forward, opposite of what I need.

    I need it to angle back so I can put the slave cylinder as far back as possible. My F1 steering box is roughly right next to the oil filter so theres not much room left for the slave. Plus I need to have a little room to get to the bleeder. The straight out 60s truck fork will probably work, but everything would be tight and the rod would be super short.

    I cant use one of those Nova slanted bellhousings because that would put the slave down close to the full length headers. Plus I already have a standard Lakewood so I dont want to change now.

    I am very leary of using a hydraulic bearing since Ive read so many stories of those leaking.

    And I prefer to not use a puller type slave since it would be hanging out in the middle of nowhere and would require some strange brackets to clear the shift linkage.
     
  9. Fordors
    Joined: Sep 22, 2016
    Posts: 970

    Fordors
    Member

    I like the ‘63^ Corvette fork, instead of the typical GM z-bar to fork rod that fits into a depression the ‘vette fork has a positive connection with a through bolt. One cut and you could reverse and weld it and the rod to fork connection will be simple.
     
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  10. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    Heres some shots of where Im at. The pics make it look like theres tons of room. But its tighter than it appears. Plus once the body is on there and trying to adjust or bleed over some fenders will be fun. I think I can pick up a small amount of room by switching to a shorter pivot ball. But Id still like some more.

    20180313_183122.jpg 20180313_182958.jpg
     
  11. There were some Chevy hydraulic clutch bellhousings that had the clutch fork and slave cylinder on the passenger side if that would give you any more room.
     
  12. Pete Eastwood
    Joined: Jul 27, 2011
    Posts: 594

    Pete Eastwood
    Member
    from california

    I've used the Lakewood version for years in '32's
     
  13. vtx1800
    Joined: Oct 4, 2009
    Posts: 666

    vtx1800
    Member

    was there a bracket for the slave cylinder welded on the bell housing? Did you have clearance issues and have to remove it? This is what my bell housing looked like before I torched it off. I am sorry that I don't have any pictures (that I know of) when I was still using the hydraulic clutch.


    scattershield before cutting of clutch bracket.JPG
     
  14. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    No, my bell didnt have a slave bracket. I will fab up something once I get its location determined.
     
  15. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    The fork pictured on the Northern site has the right curve, but unfortunately that just looks like a stock photo. When I searched a different site for each of the vehicles listed, the forks were different. I wish I knew what it actually fits.
     
  16. Rocky
    Joined: Mar 3, 2001
    Posts: 14,385

    Rocky
    Classified Editor

    Hang on chris...I'm gonna send you a photo of something that may work for you.
     
  17. Rocky
    Joined: Mar 3, 2001
    Posts: 14,385

    Rocky
    Classified Editor

    Here...this is an early 50s chevy passenger car fork. I think it came out of my old 50 delivery 216/3 speed. Takes a regular later throwout bearing and snaps over any GM pivot ball. I'm using one behind my Pontiac motor with a muncie 4 speed. I believe I have an extra one if you think it'll work. clutchfork1.jpg clutchfork2.jpg
     
  18. squirrel
    Joined: Sep 23, 2004
    Posts: 38,972

    squirrel
    ALLIANCE MEMBER

    That style arm can also be heated and bent as needed.

    Beware the geometry...make sure there is sufficient travel, because things change when you move that outer pivot point back. Hard to explain, but when you don't get enough travel, it's not fun.
     
  19. Rocky
    Joined: Mar 3, 2001
    Posts: 14,385

    Rocky
    Classified Editor

    Yeah, Jim brings up a good point. Notice this arm has very little difference in length from pivot to throwout and pivot to linkage point, prolly not much over a 1:1 ratio. And if a guy was to heat and bend it that ratio would get even closer to 1:1.
    Makes for a stiff clutch pedal with danger of going over center on a diaphram-style pressure plate. [lots of travel at the throwout bearing] Just a few things to consider.
     
  20. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    Rocky, that style of fork just might do the trick. I wouldn't plan on bending it any. The 3/4" or so jog it has should be enough for me to move my slave back just enough to give some clearance to the bleeder (from the steering column). Please look to see if you have an extra useable one.

    I bet the ratio of that fork is the same as 90% of the GM arms out there.

    The slave I plan to use is for a '60-62 Chevy truck, so I'd think it would have enough travel in it.
     
  21. Rocky
    Joined: Mar 3, 2001
    Posts: 14,385

    Rocky
    Classified Editor

    OK, I have a little sumthun to do before I check...send me a PM with your address on it.
     
  22. Couldn't you just saw a hole in the other side of the bell and mount the whole works on the right side like Chevy did?

    Sent from my Nexus 5X using The H.A.M.B. mobile app
     
  23. Fordors
    Joined: Sep 22, 2016
    Posts: 970

    Fordors
    Member

    Possible, but it would also require drilling, tapping and counter-boring for the fork pivot ball.
     
  24. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    Cutting holes in it would nullify the SFI of the bellhousing.
     
  25. Atwater Mike
    Joined: May 31, 2002
    Posts: 8,175

    Atwater Mike
    Member

    Substitute a '53-'56 steering box. Flange needs to be trimmed, BUT! The steering mast jacket is on top, giving just oodles of room to bleed that pesky slave.....

    Maybe this is why so many 'lazy hot rods' have automatic transmissions...:rolleyes:
     
  26. Corn Fed
    Joined: May 16, 2002
    Posts: 2,294

    Corn Fed
    Member

    I started the whole chassis setup journey with a F100 box. That was my initial direction. But I didn’t want to do the whole welded on flange thing. I know it’s been done 1000’s of times, but I prefer not to cut/weld steering parts if I can help it. I will get there with this setup, it just will take a little sorting.

    And YES, this is exactly why so many cars have automatics in them. But the effort also makes the manual cars that much cooler.
     
  27. Rocky
    Joined: Mar 3, 2001
    Posts: 14,385

    Rocky
    Classified Editor

    Amen, brotha
     
  28. Sorry, didn't realize you were racing. Maybe should have guessed since it was an aftermarket bell.

    Could always put the bleeder down and take it loose to bleed it :eek:, gotta have a hose on it anyway.
    Sorta stupid sounding; but I've had to work on equipment that wasn't much different.
     

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