SAAC Forum

The Cars => 1967 Shelby GT350/500 => Topic started by: bhoulis on August 11, 2018, 05:22:01 PM

Title: GT350 clutch linkage alignment
Post by: bhoulis on August 11, 2018, 05:22:01 PM
Today I mocked up my engine , hipo exhaust manifolds, hipo h-pipe, 390GT clutch fork and hipo z-bar.I'm wondering if this looks correct. (Hope the pics load, first time following the tutorial) There seems to be quite a bit of misalignment between the lower arm of the z-bar and the end of the clutch fork, almost 3 inches, which I believe is the approximate difference in length between the 390 and 289 clutch forks. The fist pic shows an aluminum bar held from the z-bar rod attaching point to the clutch fork "push point". Looks like a pretty radical angle that would put alot of twisting on the z-bar and rod. Z-bar and fork were purchased from vendors who are on these forums, both from the upper midwest, so I'm pretty sure they sold me the right pieces. Bellhousing is a C5DA-A piece, if that matters. Any help appreciated. Brian
(http://www.saacforum.com/gallery/239-110818170109.jpeg)
(http://www.saacforum.com/gallery/239-110818164940.jpeg)
Title: Re: GT350 clutch linkage alignment
Post by: Bob Gaines on August 11, 2018, 05:30:26 PM
Quote from: houlis on August 11, 2018, 05:22:01 PM
Today I mocked up my engine , hipo exhaust manifolds, hipo h-pipe, 390GT clutch fork and hipo z-bar.I'm wondering if this looks correct. (Hope the pics load, first time following the tutorial) There seems to be quite a bit of misalignment between the lower arm of the z-bar and the end of the clutch fork, almost 3 inches, which I believe is the approximate difference in length between the 390 and 289 clutch forks. The fist pic shows an aluminum bar held from the z-bar rod attaching point to the clutch fork "push point". Looks like a pretty radical angle that would put alot of twisting on the z-bar and rod. Z-bar and fork were purchased from vendors who are on these forums, both from the upper midwest, so I'm pretty sure they sold me the right pieces. Bellhousing is a C5DA-A piece, if that matters. Any help appreciated. Brian
(http://www.saacforum.com/gallery/239-110818170109.jpeg)
(http://www.saacforum.com/gallery/239-110818164940.jpeg)
Brian if the vendors sold you a Z bar then that is your problem . The 67/68 hipo Z bar is not reproduced. You will have to use the normal SB clutch fork if using a 66 hipo Z Bar.
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 11, 2018, 05:35:25 PM
So.......... That z-bar I posted a pic of isn't a 67 style hipo bar, The vendor said it was the last of a run he had made a few years back. If not a 67 then what is it, or close to? Does anyone have a pic of an authentic 67 hipo z-bar? B
Title: Re: GT350 clutch linkage alignment
Post by: Bob Gaines on August 11, 2018, 09:21:17 PM
Quote from: houlis on August 11, 2018, 05:35:25 PM
So.......... That z-bar I posted a pic of isn't a 67 style hipo bar, The vendor said it was the last of a run he had made a few years back. If not a 67 then what is it, or close to? Does anyone have a pic of an authentic 67 hipo z-bar? B
I wasn't aware that anyone reproed that particular Z bar. It looks close from what I can see in the picture but can't be for sure without a side profile shot.
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 11, 2018, 10:29:17 PM
Side view as requested. The difficulty I see is that the lower arm, when looking at the piece front to back, or perpendicularly to the round tube,  should be more in line with the upper bar. This would move it over the approximate 3 inch difference to compensate for the longer 390 fork. I have yet to find a picture of a verified 67 hipo bar.  I put in a request for a pic at Concours Mustang Forums. Hopefully something surfaces. Roswell aliens, Loch Ness monster, 67 Hipo z-bars. The search goes on. B
(http://www.saacforum.com/gallery/239-110818165550.jpeg)
Title: Re: GT350 clutch linkage alignment
Post by: JD on August 12, 2018, 09:28:31 AM
Maybe a repro'd Boss 302 styled Z-bar, that can work with on '67's GT350's, but as Bob stated not correct.
Title: Re: GT350 clutch linkage alignment
Post by: Bossbill on August 12, 2018, 06:10:09 PM
That's what the Z bar in my 70 Boss looks like.

I appear to be in the same boat as houlis.
Title: Re: GT350 clutch linkage alignment
Post by: shelbydoug on August 12, 2018, 08:27:37 PM
If you want the clutch to work right, you need to make your own z-bar. Your observation about where the lower arm should be located is correct. The thing also needs to be at least heat treated but would be better to just reinforce it on both arms by doubling the thickness.

If you don't, it is going to twist like a pretzel unless you use it with the original 2600 pound clutch. That was never serviced through Ford. It was only a production line part.

The replacement clutch Ford parts sold was 2800 pounds. A standard street aftermarket clutch is going to be in the 3,000-3,200 range and will turn that z-bar into a wet noodle.

It would also be an excellent idea to replace the plastic bearings with real roller bearings.
Title: Re: GT350 clutch linkage alignment
Post by: 67350#1242 on August 12, 2018, 09:46:42 PM
Here are pictures of C7ZZ-7528-H NOS Ford service part for reference.  (from VMF post in 2016)
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 12, 2018, 09:56:32 PM
Thanks for the replies. Looking into oilite bushings to replace the crappy plastic ones. I can't imagine they lasted more than a month or two when these cars were daily drivers. At this point I would just like to see a picture of an assembly line z-bar. I'm trying to find pictures of the underside of restored cars hoping to see one. All i've seen so far are the B302 style arm and short fork. Fabricating one is an option down the road. Trying to stay as correct as possible but it seems these bars non existent. Like bigfoot and the Loch Ness monster, a lot of sightings but no good photos. B
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 12, 2018, 09:58:51 PM
Looks like they were servicing it with the B302 style. I wonder how many people got back to their garages with that piece and realized they would also have to change the fork. B
Title: Re: GT350 clutch linkage alignment
Post by: 67350#1242 on August 12, 2018, 10:06:51 PM
QuoteLooking into oilite bushings to replace the crappy plastic ones.
An EBay vendor carries brass bushings to replace the crappy plastic ones.  I've had some in my Shelby for 6 or 7 years and still working good and tight.
https://www.ebay.com/itm/Early-Bronco-Early-Mustang-Clutch-rod-bushing-METAL-PN-EBMCRB/261464757864?hash=item3ce0839668:g:DtwAAOxy3yNTfCNE
Title: Re: GT350 clutch linkage alignment
Post by: Bob Gaines on August 12, 2018, 10:14:03 PM
Quote from: 67350#1242 on August 12, 2018, 10:06:51 PM
QuoteLooking into oilite bushings to replace the crappy plastic ones.
An EBay vendor carries brass bushings to replace the crappy plastic ones.  I've had some in my Shelby for 6 or 7 years and still working good and tight.
https://www.ebay.com/itm/Early-Bronco-Early-Mustang-Clutch-rod-bushing-METAL-PN-EBMCRB/261464757864?hash=item3ce0839668:g:DtwAAOxy3yNTfCNE
Cool. :)
Title: Re: GT350 clutch linkage alignment
Post by: Bossbill on August 13, 2018, 01:39:02 AM
Did that 20 years ago when I had clutch linkage issues on the B3. Still working.
You drill out the hole slightly bigger for an almost press fit and insert the oilite or sintered bronze bushing.

I too would love to see a picture. From what little I can make out of other cars, the top curved portion may be correct.
Title: Re: GT350 clutch linkage alignment
Post by: roddster on August 13, 2018, 10:11:04 AM
  Seems to me the clutch throw out arm is too long.  The arm of the cross shaft almost aligns with the block edge on my GT 350.  Your clutch throwout arm end seem too far left. (wrong side of the exhaust pipe)
Title: Re: GT350 clutch linkage alignment
Post by: shelbydoug on August 13, 2018, 10:34:25 AM
Quote from: roddster on August 13, 2018, 10:11:04 AM
  Seems to me the clutch throw out arm is too long.  The arm of the cross shaft almost aligns with the block edge on my GT 350.  Your clutch throwout arm end seem too far left. (wrong side of the exhaust pipe)

That's right or as we tell the kids, "your other left".  ;)

Exactly how the geometry of that set up as shown is going to work is beyond me.

There are no Ford logos or part numbers stamped on those parts. IF the judges choose to climb in there and then decide to deduct points from you for having the wrong part, but it works...I'd take the hit.

The other possibility is that is the wrong H pipe and fork for the car. The z-bar is made to the entire setup. Once you start mixing and matching, you are screwed.
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 13, 2018, 05:08:38 PM
Yes. The 390 clutch fork does not seem to work with the hipo bars that people are showing. The question is, are these correct assembly line style z-bars, or a later Boss302 style that superseded the original style. TSB, service replacement. If so then people would have had to change the clutch fork to the shorter style if they were replacing their original z-bars. If these are the correct style bar then the whole argument of "390 clutch forks on hipo motors", as shown in the parts books and supported by some of the more experienced in the Shelby community is a mistake. Waiting to see that one photo of the mythical assembly line z-bar or a good up close undercarriage shot showing the longer 390 fork installed. I'm going to put my ride together with a short fork and the B302 style bar that I paid a chunk for. I'll keep the 390 fork, that I paid another chunk for, until there is some sort of resolution one way or the other. Brian
Title: Re: GT350 clutch linkage alignment
Post by: shelbydoug on August 13, 2018, 06:51:35 PM
The shorter the fork, the more effort is needed. I think that you have the thinking correct. The fork that you have does not match the z-bar that you want to use.

Since no one is rushing to post photos, I assume that they aren't sure what they have in use now?

My z-bar is custom made and not stock so there isn't much point in showing what I have but I do know that I have the long fork and the short lever arm on the z-bar in like you say, about 3" from the bell, on the other side of the pipe.

I think that your problem may be a lack of availability of the short fork?
Title: Re: GT350 clutch linkage alignment
Post by: texas swede on August 13, 2018, 07:24:34 PM
Here is a picture of the different Z-bars including the 67 K-code and GT350
Texas Swede
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 13, 2018, 07:53:24 PM
Thanks Texas. Based on this, the 390 forks for hipos message is false. Brian
Title: Re: GT350 clutch linkage alignment
Post by: JD on August 13, 2018, 08:32:55 PM
Texas Swede Thanks for this image!

(reposted rotated, hope you don't mind)
Title: Re: GT350 clutch linkage alignment
Post by: Bossbill on August 13, 2018, 08:49:04 PM
This unicorn search started with this thread:
http://www.saacforum.com/index.php?topic=2107.0

In it the various clutch forks were shown with the final determination possibly made by the MPC that the "K/390" fork was concours correct.
Based on that information both Brian and I purchased the longer "K/390" forks. These suckers were fairly tough to find with an impressive price tag. Buy hey, it's a Shelby.

After Brian's mock-up I tried my long fork as well. We are 3" out of bed.

I dug out my Z bar and thought "Oh crap, Brian has the same Z bar as I do. Do I have an issue too?"

So here is the Z bar on my car. It looks exactly like the pic of the 67 Z bar on top left that texas swede posted. And Brian's. I tried to orient it the same way as in the above pic.

If we all agree on this Z bar then we have to go back to fork thread and figure out which fork we REALLY need.

Title: Re: GT350 clutch linkage alignment
Post by: Bob Gaines on August 13, 2018, 10:14:31 PM
Quote from: Bossbill on August 13, 2018, 08:49:04 PM
This unicorn search started with this thread:
http://www.saacforum.com/index.php?topic=2107.0

In it the various clutch forks were shown with the final determination possibly made by the MPC that the "K/390" fork was concours correct.
Based on that information both Brian and I purchased the longer "K/390" forks. These suckers were fairly tough to find with an impressive price tag. Buy hey, it's a Shelby.

After Brian's mock-up I tried my long fork as well. We are 3" out of bed.

I dug out my Z bar and thought "Oh crap, Brian has the same Z bar as I do. Do I have an issue too?"

So here is the Z bar on my car. It looks exactly like the pic of the 67 Z bar on top left that texas swede posted. And Brian's. I tried to orient it the same way as in the above pic.

If we all agree on this Z bar then we have to go back to fork thread and figure out which fork we REALLY need.
Still digesting all of the facts being discussed however the top arm in your picture appears to have a different bend when compared to the picture in reply 18/20. You asked.
Title: Re: GT350 clutch linkage alignment
Post by: Bossbill on August 13, 2018, 10:53:53 PM
Bob -- I think that's cell camera parallax where the lens distorts the angle of things.
Are you looking at the angle between the top curved bar and the hollow tube?
All of the angles between the tube and the top and bottom bars are 90 deg, regardless of what the photo purports to show.

If you want other pics, let me know and I'll use a real camera.
Title: Re: GT350 clutch linkage alignment
Post by: Bob Gaines on August 13, 2018, 11:22:04 PM
Quote from: Bossbill on August 13, 2018, 10:53:53 PM
Bob -- I think that's cell camera parallax where the lens distorts the angle of things.
Are you looking at the angle between the top curved bar and the hollow tube?
All of the angles between the tube and the top and bottom bars are 90 deg, regardless of what the photo purports to show.

If you want other pics, let me know and I'll use a real camera.
Yes that angle looks taller in your picture compared to the other but that might be a illusion.
Title: Re: GT350 clutch linkage alignment
Post by: shelbydoug on August 14, 2018, 07:56:28 AM
It's the location of the short arm on all of them that determines the length of the fork. IF the correct location of the short arm needs to be as close as possible to the bell, then a shorter fork HAS to be used.

You can't possibly mix the longer fork to those z-s. The geometry would be terrible.

IF all you can use is the longer fork, then you HAVE to relocate the short arm 3 inches out, to the other side of that exhaust.

With the shorter fork, the 2600# clutch makes sense then. You likely will need power assist to the clutch pedal to use and aftermarket clutch with the shorter fork AND you positively will tear up and twist everything in site.

Title: Re: GT350 clutch linkage alignment
Post by: 67350#1242 on August 14, 2018, 08:37:56 AM
QuoteWith the shorter fork, the 2600# clutch makes sense then. You likely will need power assist to the clutch pedal to use and aftermarket clutch with the shorter fork AND you positively will tear up and twist everything in site.
That is why most every driver car you see will have a reinforced Z-bar.  I'll bet even the light clutch caused the top arm of the bar to twist over time. 
Title: Re: GT350 clutch linkage alignment
Post by: shelbydoug on August 14, 2018, 09:19:28 AM
Do you know how many people don't even realize that the z is twisted? I would say...most!

That is what I expect to happen with it. Some have been successful with having the original "hardened" but by doing so it also becomes brittle and can crack through the high stress spot just above the weld.

I just double the top arched piece and quench the weld in water. That will harden the steel about as much as you can do anyway.

Great pic. Thanks for posting that. Seeing is believing.
Title: Re: GT350 clutch linkage alignment
Post by: Bossbill on August 14, 2018, 01:53:18 PM
Ok, I'd like wrap up the Z-bar portion of the 67 GT350 clutch linkage.


Perhaps it's time to move on and figure out what the clutch fork of a 67 HiPo looks like that matches this arm. See http://www.saacforum.com/index.php?topic=2107.0
Title: Re: GT350 clutch linkage alignment
Post by: bhoulis on August 15, 2018, 07:12:45 PM
Update. Received my new Ford tooling clutch fork today, the one listed for regular 67 289s, and release rod. Mocked up and looks like there shouldn't be any alignment troubles. The pic with rod installed has the z-bar about 1/4" shy of being all the way on the pivot because the rod was hitting the wooden engine cart. But the felt washer should just about make up for the space so should be a good representation of how things will be once installed. Middle pic has 2 pieces of threaded rod nutted together to make a shorter rod to check alignment with zbar pushed all the way onto the block pivot. This was before I realized the felt washer would take up the space. Hope this helps get us towards a more final conclusion. There may be other factory original parts out there for this combination but these are readily available to keep things moving. Hope this helps. Brian
(http://www.saacforum.com/gallery/239-150818182019.jpeg)

(http://www.saacforum.com/gallery/239-150818181936.jpeg)

(http://www.saacforum.com/gallery/239-150818182118.jpeg)
Title: Re: GT350 clutch linkage alignment
Post by: Bossbill on August 27, 2018, 08:32:22 PM
Yes, that looks good.
While poking around in another pile of parts I found what appears to be a 66 HiPo fork.
I placed it next to the fork that's been in my car for well over 35 years -- the now famous snake tongue fork. Here is pic of both. Sorry I didn't line them up, but the pic was for another purpose.

They are the same distance from pivot to T/O bearing end and from pivot to clutch rod end. The HiPo fork is 1.675 inside the U shaped T/O bearing end -- the snake fork is 0.050 wider.
Either fits on the stock T/O bearing. The only difference appears to be the end.

So far no one has corroborated the correct 67 HiPo fork.

(http://www.saacforum.com/gallery/411-270818201304.jpeg)
Title: Re: GT350 clutch linkage alignment
Post by: 67350#1242 on August 27, 2018, 10:01:59 PM
Same snake tongue fork was on my GT350 when I purchased in 1989.