Clutch Spring Assist - question

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Q1SVT

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Has anyone tested the spring rate or knows what it is?

The spring available is not for 351C or big blocks... They are for 302 or six cylinders [softer pressure plate]
That's okay for what I want. Looking for a spring to return clutch pedal to full up position, more so than assisting...

Since the bracket that holds the spring is not available, I'll fabricate something, I'm thinking a 2023 Steeda stang S550 spring @ 35# might be a good/better option.

Thanks
Screenshot 2025-01-15 at 10.53.58 AM.png Screenshot 2025-01-15 at 11.00.39 AM.png
 
If you're referring to the clutch assist spring that mounts on the top of the pedal arm and the bracket, you do NOT need it there if you're using a diaphragm style clutch. I fact if you are using a diaphragm clutch, it MUST be removed and it can be a bi*ch to remove so be careful.
If you're using a long finger style (as original), then you need that spring.
 
Thanks Stanglover and others

I know what you’re saying…. I’m going to a ford quadrant style, cable setup and those cars had a simple torsion spring to return pedal to top. The clutch setup for those cars need through out bearing to have a small offset from pressure plate…. Since ford went hydraulically they started using assisted clutch springs. I’m using a newer style double disk clutch good for my HP/TQ, but can handle 800+.

I’m trying to help my pedal to return fully to top. Looking for info on spring rate…. I have the spring for the six cylinders and can compress it by hand. Know steeda is 35#. I plan on setting up testing soon with one of the pedal supports while motor / trans is on engine stand… tuning clutch operation from pedal to pressure plate. Before installation. Reason why I have extra complete support for testing out of the vehicle…

IMG_5252.jpeg
 
Thanks Stanglover and others

I know what you’re saying…. I’m going to a ford quadrant style, cable setup and those cars had a simple torsion spring to return pedal to top. The clutch setup for those cars need through out bearing to have a small offset from pressure plate…. Since ford went hydraulically they started using assisted clutch springs. I’m using a newer style double disk clutch good for my HP/TQ, but can handle 800+.

I’m trying to help my pedal to return fully to top. Looking for info on spring rate…. I have the spring for the six cylinders and can compress it by hand. Know steeda is 35#. I plan on setting up testing soon with one of the pedal supports while motor / trans is on engine stand… tuning clutch operation from pedal to pressure plate. Before installation. Reason why I have extra complete support for testing out of the vehicle…

View attachment 96732
Ah well, that's a whole different kettle of fish. A different ball game all together.
Please let us know how it all works out.
 
lol… yes she is a different kind of CAT, and she has been good to me since I ordered her new.
I switched teams after following Wayne Gapp carry his cats wheels down Detroit Drag Strip.

His finger prints are on our 4V heads as a ford engineer
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The overcenter spring is the same regardless of engine. Ford may have originally had individual springs, but it was distilled down to just the C8OZ-A spring.

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Thanks… is that page from an interchange book?
I’m still trying to figure out rate… I think the C8OZ is more than needed. Guess I need to stop by a head shop and get them to measure one
 
Now I'm lost!!
What car exactly do you have? Nothing is listed on your intro on the left.
I started my Cleveland life with a used 70 4V cougar 4 speed from Ford’s B lot. Then purchased a new 73 2V C6 cougar and installed the 70 4V to get around insurance costs/ rules on performance. Someone ran into the 70 while it was parked.
 
Thanks… is that page from an interchange book?
I’m still trying to figure out rate… I think the C8OZ is more than needed. Guess I need to stop by a head shop and get them to measure one

Came from the 65-72 Ford Master Parts Catalog. Unfortunately, I only have the final version. The earlier versions may have more info.

IMO the overcenter spring is not an "assist" device, merely a method to return the pedal without adding excessive pedal effort like the early cars with the extension spring. .
 
There were two different size springs that I know of. I have them both. One is thicker with one less coil and more resistance when compressing than the other. The new ones out there are even thinner. Perhaps it was the 429s that had the heavier spring.
 
Hello,
Im looking for Some info for my T-5 Conversion on my 73 mach 1. Do I need a Clutch Pedal return spring? I used the Stock pedal mount and Added the MDL Clutch Pedal, I am using a Plain Jane Diapram Clutch with a Fox body style clutch cable. Is the Pressure plate adequate to return the Clutch pedal or will it drag/ need assist? IF I need a spring which one? Thanks!
 

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Added the MDL Clutch Pedal, I am using a Plain Jane Diapram Clutch with a Fox body style clutch cable. Is the Pressure plate adequate to return the Clutch pedal or will it drag/ need assist?
… are you using a m d l knockoff cable …

… Is your clutch fork one for a fox stang…

I’m going to say Yes

The best advice is for you to spend time understanding how to correctly setup and adjust that setup. Fox and later use a pivot ball (not like a top loader).

The fox has a spring. Like with 71-73, people with fox’s say you do not need it others say you do.

There are many many posts. I’m guessing on a fox sight, maybe here.

I believe at this time a soft spring is needed to 1) return the pedal to top. 2) stop pedal from making noise 3) to allow the through out to fully release from the pressure plate.

Jm2c Aka an opinion
 
I tend to agree with you on the Soft Spring, I think the heavy spring would be for a Linkage set up.
SO how do I install a soft Spring? any insight? I cant find much info
 
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