Clutch Z-bar: All the same?
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Clutch Z-bar: All the same?
Quick simple question. Are all the model year parts (both C2 and C3) the same design (same arm lengths and angles)?
My guess is Yes, but I'm open to correction.
Thanks for any constructive input.
My guess is Yes, but I'm open to correction.
Thanks for any constructive input.
Le Mans Master
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From: Watkinsville, GA and Glen Cove, NY
This was a quote from JohnZ on another thread to the same question you asked.
“There were some subtle differences in the angular relationship between the upper and lower levers over the years both between different years of SB's and between SB and BB in certain years, but I haven't researched it. Most of the resto houses just sell two - one for '63-'65 SB's, and one for '65-'67 BB, '66-'67 SB, and all '68-'81. The differences really only matter in that you also need the matching lower pushrod to the clutch fork with each one, and there are three of those.
”
“There were some subtle differences in the angular relationship between the upper and lower levers over the years both between different years of SB's and between SB and BB in certain years, but I haven't researched it. Most of the resto houses just sell two - one for '63-'65 SB's, and one for '65-'67 BB, '66-'67 SB, and all '68-'81. The differences really only matter in that you also need the matching lower pushrod to the clutch fork with each one, and there are three of those.
”Last edited by 69ttop502; Jan 24, 2019 at 09:49 PM.
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Mine came with 2 holes from Keisler Engineering. I drilled another one down lower, so it moves the lower arm faster for less pedal travel to disengage the clutch.
are you going to be at the 24 hours of daytona race on Saturday. We were thinking about flying in
are you going to be at the 24 hours of daytona race on Saturday. We were thinking about flying in
Last edited by gkull; Mar 31, 2023 at 11:17 AM.
Thread Starter
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Lotsa good information here, gentlemen. I do appreciate it.
I'm currently cutting up some aluminum tubing and plate to make a slightly lighter z-bar (I'm running out of ideas to get additional weight off the front of the car). I have a "spare" z-bar on the shelf to use while I make the welding jig, but I don't know the actual vehicle it came off of. I'll do some measurements of this bar, and then see if it's better to just pull the current one off the car to use when making the welding jig.
Thanks again.
I'm currently cutting up some aluminum tubing and plate to make a slightly lighter z-bar (I'm running out of ideas to get additional weight off the front of the car). I have a "spare" z-bar on the shelf to use while I make the welding jig, but I don't know the actual vehicle it came off of. I'll do some measurements of this bar, and then see if it's better to just pull the current one off the car to use when making the welding jig.
Thanks again.
Race Director
Joined: May 2003
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From: California
Lotsa good information here, gentlemen. I do appreciate it.
I'm currently cutting up some aluminum tubing and plate to make a slightly lighter z-bar (I'm running out of ideas to get additional weight off the front of the car). I have a "spare" z-bar on the shelf to use while I make the welding jig, but I don't know the actual vehicle it came off of. I'll do some measurements of this bar, and then see if it's better to just pull the current one off the car to use when making the welding jig.
Thanks again.
I'm currently cutting up some aluminum tubing and plate to make a slightly lighter z-bar (I'm running out of ideas to get additional weight off the front of the car). I have a "spare" z-bar on the shelf to use while I make the welding jig, but I don't know the actual vehicle it came off of. I'll do some measurements of this bar, and then see if it's better to just pull the current one off the car to use when making the welding jig.
Thanks again.
Hardness on the Z bar....
I also put in an extra hole so as to have a quicker and shorter clutch throw.. BUT,,,,,,,,,,,,,,,,,,,,,................ .............
the mettle is friggen hard!!!! I could NOT drill this mettle... so I had to have my Zbar water jetted to get the third hole..
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Le Mans Master
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Lotsa good information here, gentlemen. I do appreciate it.
I'm currently cutting up some aluminum tubing and plate to make a slightly lighter z-bar (I'm running out of ideas to get additional weight off the front of the car). I have a "spare" z-bar on the shelf to use while I make the welding jig, but I don't know the actual vehicle it came off of. I'll do some measurements of this bar, and then see if it's better to just pull the current one off the car to use when making the welding jig.
Thanks again.
I'm currently cutting up some aluminum tubing and plate to make a slightly lighter z-bar (I'm running out of ideas to get additional weight off the front of the car). I have a "spare" z-bar on the shelf to use while I make the welding jig, but I don't know the actual vehicle it came off of. I'll do some measurements of this bar, and then see if it's better to just pull the current one off the car to use when making the welding jig.
Thanks again.
Le Mans Master
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Mike. Do this one. My son bought me the strut kit from speed direct. $160.
It weighs nothing. Make your own brackets out of alum, and buy the cylinder. Takes 3 lbs off up high. And, it works far better. Even Doug likes it, and he is NCRS crazy.
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Well, I hope the zone I'm in isn't quite that expensive. 
To be honest, half the reason I've been on this path is just for the pure engineering enjoyment of it (most hobbies are money pits of some sort). I spent most of my adult life doing circuit design, and now I'm finally getting to get some return on my money for all the tuition dollars I spent wading through the mechanical engineering classes my freshman and sophomore years.
Oh, I agree on changing the hood prop (the weight's up front and up high). I did the hood prop/bracket setup in aluminum several years back. I did have to change the (version 1 aluminum) prop rod to a steel piece, as the aluminum rod was either too flexible or too big aesthetically.
To be honest, half the reason I've been on this path is just for the pure engineering enjoyment of it (most hobbies are money pits of some sort). I spent most of my adult life doing circuit design, and now I'm finally getting to get some return on my money for all the tuition dollars I spent wading through the mechanical engineering classes my freshman and sophomore years.
Oh, I agree on changing the hood prop (the weight's up front and up high). I did the hood prop/bracket setup in aluminum several years back. I did have to change the (version 1 aluminum) prop rod to a steel piece, as the aluminum rod was either too flexible or too big aesthetically.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Well, I hope the zone I'm in isn't quite that expensive.
To be honest, half the reason I've been on this path is just for the pure engineering enjoyment of it (most hobbies are money pits of some sort). I spent most of my adult life doing circuit design, and now I'm finally getting to get some return on my money for all the tuition dollars I spent wading through the mechanical engineering classes my freshman and sophomore years.
Oh, I agree on changing the hood prop (the weight's up front and up high). I did the hood prop/bracket setup in aluminum several years back. I did have to change the (version 1 aluminum) prop rod to a steel piece, as the aluminum rod was either too flexible or too big aesthetically.
To be honest, half the reason I've been on this path is just for the pure engineering enjoyment of it (most hobbies are money pits of some sort). I spent most of my adult life doing circuit design, and now I'm finally getting to get some return on my money for all the tuition dollars I spent wading through the mechanical engineering classes my freshman and sophomore years.
Oh, I agree on changing the hood prop (the weight's up front and up high). I did the hood prop/bracket setup in aluminum several years back. I did have to change the (version 1 aluminum) prop rod to a steel piece, as the aluminum rod was either too flexible or too big aesthetically.
The 81 has this massive battering ram that must weigh 40lbs.
Last edited by Big2Bird; Jan 25, 2019 at 08:02 PM.
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Race Director
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From: SW Florida.
I think you will find why the Z-bar metal is too hard to drill as soon as you step on the clutch with that aluminum Z-bar. The big heavy bumper brackets are a safety issue and there are many arguments when people wanna convert to 68-72 bumpers.
Thread Starter
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by derekderek;1598761554[b
]I think you will find why the Z-bar metal is too hard to drill as soon as you step on the clutch with that aluminum Z-bar.[/b] The big heavy bumper brackets are a safety issue and there are many arguments when people wanna convert to 68-72 bumpers.
Just curious.
Race Director
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From: SW Florida.
they used boat loads of cheap soft steel because, like every other 60's to 80's car it was designed to last about 5 minutes longer than the warranty period. fed govt mandated better crash safety so they used more. once cars cost 50 to 60k new and fed govt mandates certain fuel economy standards, out comes the Aluminum, Magnesium and composites... they used hard steel in the z-bar cuz the cheap soft stuff didn't hold up. do I know you personally and think you have no idea what you are doing? no. do i think the AL pivot will hold up? i hope i am wrong... but there are MANY more people on this forum that can fab a z-bar than can design one.
Last edited by derekderek; Jan 26, 2019 at 11:28 AM.
Thread Starter
Tech Contributor
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
they used boat loads of cheap soft steel because, like every other 60's to 80's car it was designed to last about 5 minutes longer than the warranty period. fed govt mandated better crash safety so they used more. once cars cost 50 to 60k new and fed govt mandates certain fuel economy standards, out comes the Aluminum, Magnesium and composites... they used hard steel in the z-bar cuz the cheap soft stuff didn't hold up. do I know you personally and think you have no idea what you are doing? no. do i think the AL pivot will hold up? i hope i am wrong... but there are MANY more people on this forum that can fab a z-bar than can design one.
Did I at least get this side part of the project correct?
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Race Director
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From: Long Island
If the AL fails , you could go to Dupont Vespel Bearings and Hemi rod ends. It may help. You would have to machine a step in the tube or insert another tube to make the step.
Experimenting is always fun .. Best of luck..
Experimenting is always fun .. Best of luck..
