Jump to content

Clutch- what have I done


Recommended Posts

So heres a update. I got car running today and took on a easy maiden voyage. THe clutch wasnt quite as bad as I thought when sitting in garage with car off.

I think its livable. I see people post that they wish the didnt go stock, and I dont want to be that guy either where you get on it and it spins the clutch. I think I will drive it for 1 summer and see how I feel about it. It may be worth it in the long run if burnouts dont bother it. Thanks all.

Link to comment
Share on other sites

  • Replies 44
  • Created
  • Last Reply

Top Posters In This Topic

Frictional force is directly proportional to the applied load. In other words, if you increase the force required to operate the clutch (pressure plate) by 25% the frictional force (the force required to overcome the static friction -stiction- and kinetic friction -friction when it is moving) at the bushings and metal-to-metal connections also goes up 25%.

 

Reducing the friction with bearings and Heim joints will make a noticeable difference.

 

 

“If you can't explain it simply, you don't understand it well enough.”

--Albert Einstein

 

Link to comment
Share on other sites

Digithead,

Suck it up big boy,

The way I look at it you can rollerize your complete clutch release mechanism (2 roller bearings at the

pedal assembly, heim joints on the rod ends and spherical bearings at the z bar.

if you do all of this it will get you back to the stock feel with the wimpy pressure plate.

I did all of the rollerizing before I went to the 408.

Boilermaster

Thanks for the advice, makes sense. Is there some kit out there or did you basically pull it all out and find bearings that fit?

I've never pull pedal/linage assembly so I am assuming its all just simple bushings, so you figured out bearings would be better.

THanks for the links but that kit at CJ Pony only goes to 1970. Mine is a 1973.

a roller and heim type system only eliminates friction cause by the mechanical linkage so it will not make a huge difference in the amount of force required to depress the pedal.

 

yes the stock pedal support uses bushings.

 

heres the instruction info and the kit info for the pedal support conversion.

 

http://www.virginiaclassicmustang.com/howto/instructions/64-70ClutchPedalBearingInstr.pdf

 

https://www.cjponyparts.com/roller-bearing-clutch-and-brake-pedal-support-bushing-kit-1965-1970/p/HW1015/

 

 

SOME HEIM JOINT CONVERSION INFO

 

http://forums.vintage-mustang.com/general-discussion-non-vintage-mustang/533472-heim-joint-clutch-linkage.html

 

Zbar-001.jpg

Link to comment
Share on other sites

 

THanks for the links but that kit at CJ Pony only goes to 1970. Mine is a 1973.

 

 

Ahhh, sorry about that. I had 69/70 on the brain because that's one of the cars I am currently helping somebody with.

 

 

Reducing friction is great and I am all for it, however, my point is that if it takes nearly 2 feet to depress a clutch with a standard mechanical linkage, It will still be hard to depress with a heim joint system. Just because it will be less hard does not mean that it will still not suck to drive it in traffic etc. I know this for a fact because I have already done this exact test.

 

Reducing the pressure of the pressure plate also reduces the frictional load on the stock linkage system, which is why it is better to install a lighter pressure plate if a car has one that is pretty hard to depress or at least tiring to depress many times in a row if it is driven in traffic.

 

In short, heim joints and bearings will not make a 2800 lb clutch feel like a stock one, so the difference will not be day and night, however, one will definitely be able to feel an improvement.

Link to comment
Share on other sites

 

THanks for the links but that kit at CJ Pony only goes to 1970. Mine is a 1973.

 

 

 

The pedal support kit is the same thru 73 but 69 thru 73 will need modifications to the pedal support to make it work.

Link to comment
Share on other sites

So you're thinking Centerforce disc with a stock type PP?

 

No, because the stock pressure plate is too light even though they used them on boss cars and cobra jets etc. The stock 11" ford cobra jet plate is 1850 lbs at the most and the stock 10" ones are round 1575. I know this because I took a few stock pressure plates to mcleod and had them measure them for me so I knew what the baseline pressure was and could then determine what pressure I wanted to use. On stock and mild performance builds that usa a 10" plate, I use 1650 pressure. This along with the bigger 10 1/2" mcleod set up is more than enough for moderate builds that aren't being drag raced. Mcleod will make whatever pressure one wants for no additional cost. I helped talk them into making a line of plates that were just slightly stiffer than stock also but I don't know if they advertise those anymore.

 

I use 2250 on some apps and that is too stiff for my liking in heavy traffic but I'm not a weight lifter easier, plus I'm a bit lazy. I have never used a centerforce disc with a mcleod pressure plate but I see no reason why it would not fit and work properly. I do know for a fact that the centerforce street discs are far better than the mcleod street discs which is why I suggested this. I also have some experience with both centerforce and mcleod dual friction discs and didn't notice any difference but I didn't do back to back drag race tests with them etc.

 

Good info, thanks! The guys I know using the C-force dual Friction had excellent luck with them, until the power levels exceeded the clutch's capacity. Two friends are using the RXT dual disc and love them.

 

So heres a update. I got car running today and took on a easy maiden voyage. THe clutch wasnt quite as bad as I thought when sitting in garage with car off.

I think its livable. I see people post that they wish the didnt go stock, and I dont want to be that guy either where you get on it and it spins the clutch. I think I will drive it for 1 summer and see how I feel about it. It may be worth it in the long run if burnouts dont bother it. Thanks all.

 

You'll get used to it. Your left leg will get stronger as a result... :)

 

 

Link to comment
Share on other sites

OMG,

Fail, Fail,fail

(it will feel like stock with a high performance pressure plate and disc.

Or at least mine does.

Boilermaster

 

Thanks but I dont follow what is a fail fail fail? Putting in the clutch I chose, or someone elses reply?

Sorry digithead,

I mis spoke, and was trying to correct my reply.

                   Boilermaster

Link to comment
Share on other sites

I emailed mcleod to find out what pressure that plate is.

 

THank you!! THat makes sense. I never knew you could get the actual pressure in force of the pp. At least then you have some benchmark to compare by. Learn something new everyday!  I drove it a bit yesterday and its tolerable. Gotta wear sneakers for sure, no more sandals driving or something bad might happen lol (read me going thru the back of my garage).

Link to comment
Share on other sites

I emailed mcleod to find out what pressure that plate is.

 

THank you!! THat makes sense. I never knew you could get the actual pressure in force of the pp. At least then you have some benchmark to compare by. Learn something new everyday! 

 

Yes it makes it extremely simple and they even used to list the pressure of the plates in their online catalog but they don't have that anymore so it makes it difficult to know what the heck you are installing. It just seems many of the mfg's are going downhill a bit these days. I will let you know what I find out.

 

They can also install different springs in yours so I also asked how much that would be.

Link to comment
Share on other sites

ok, well this makes absolutely no sense at all. Mcleod says that pressure plate is only 1800 lbs which is fairly close to stock on the high perf engines, so it definitely should not be overly hard to push the pedal in.

 

They can respring it to make it lighter for $150.00 but then you run the risk of having it wear prematurely or possibly slip if you have good traction and dump the clutch. If you don't have sticky tires and don't beat the heck out of it frequently and your linkage is not causing any problem, you could have it resprung 100 lbs lighter and use their dual friction disc and it will be fine.

 

Also, if you find it "almost" tolerable but would like it a little easier to push the pedal in, then installing the needle bearing kit on the pedal bracket may help enough and if it doesn't you could still add the heim joints or you could leave the pedal support and try the heim joints first which would be easier.

Link to comment
Share on other sites

That does seem light. The one I was looking at shows 2,350 lbs. Mine is also set up on a cable and not a Z-Bar.

73 Grande H Code. Headman long tube headers, T-5 Transmission, 3.70 Traclok, Lowered 1" all around, Aussie 2v heads w/ 2.19 intake, 1.71 exhaust, screw in studs, full roller cam 608/612 lift 280/281 duration LSA 112, Quick Fuel 750 CFM double pumper, AirGap intake.

 

- Jason

 

 

082-hot-rod-power-tour-2017-1970-1970s.jpg

 

Link to comment
Share on other sites

That does seem light. The one I was looking at shows 2,350 lbs. Mine is also set up on a cable and not a Z-Bar.

 

Yeah it's a bit odd. The lightest stock one is around 1575 lbs and that is pretty easy to depress. Before I went down there, the lightest one they made for a Ford was 1950 lbs.

 

2350 nearly takes me 2 feet to depress the pedal on but I'm a bit wimpy and a bit lazy but it is still a pretty stout clutch, but 1800 is not all that hard.

Link to comment
Share on other sites

The clutch pedal bearing kit is relatively easy to install once you get past removing the bracket.

Here is my experience with it: https://www.7173mustangs.com/thread-bearing-kit-for-clutch-pedal

In my case I am installing it together with a cable kit.

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

Link to comment
Share on other sites

ok, well this makes absolutely no sense at all. Mcleod says that pressure plate is only 1800 lbs which is fairly close to stock on the high perf engines, so it definitely should not be overly hard to push the pedal in.

 

They can respring it to make it lighter for $150.00 but then you run the risk of having it wear prematurely or possibly slip if you have good traction and dump the clutch. If you don't have sticky tires and don't beat the heck out of it frequently and your linkage is not causing any problem, you could have it resprung 100 lbs lighter and use their dual friction disc and it will be fine.

 

Also, if you find it "almost" tolerable but would like it a little easier to push the pedal in, then installing the needle bearing kit on the pedal bracket may help enough and if it doesn't you could still add the heim joints or you could leave the pedal support and try the heim joints first which would be easier.

 

Thanks so much for figuring all that out for me! Wow I have learned a ton. So the simple approach would probably be to just try retrofitting with needle bearing kit and see where I am at. Also, I am wondering if anyone ever "modded" the stock linkage, because technically you could lengthen a moment arm and use physics to have a more mechanical advantage when pressing, so the pressure would feel easier.

Link to comment
Share on other sites

I would suggest that you drive it some more. Clutches need a few hundred mile break in and mine definitely felt better after break in. As to modding- you have to make sure that if you are going to try and lengthen arms, etc, that you don't run into physical interference or creating more or less overall travel. I hate to be the one to ask this, but have you verified that the clutch is properly adjusted with appropriate air gap?

http://www.7173mustangs.com/gallery/1_01_07_15_8_53_18.png

 

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!

Link to comment
Share on other sites

ok, well this makes absolutely no sense at all. Mcleod says that pressure plate is only 1800 lbs which is fairly close to stock on the high perf engines, so it definitely should not be overly hard to push the pedal in.

 

They can respring it to make it lighter for $150.00 but then you run the risk of having it wear prematurely or possibly slip if you have good traction and dump the clutch. If you don't have sticky tires and don't beat the heck out of it frequently and your linkage is not causing any problem, you could have it resprung 100 lbs lighter and use their dual friction disc and it will be fine.

 

Also, if you find it "almost" tolerable but would like it a little easier to push the pedal in, then installing the needle bearing kit on the pedal bracket may help enough and if it doesn't you could still add the heim joints or you could leave the pedal support and try the heim joints first which would be easier.

 

Thanks so much for figuring all that out for me! Wow I have learned a ton. So the simple approach would probably be to just try retrofitting with needle bearing kit and see where I am at. Also, I am wondering if anyone ever "modded" the stock linkage, because technically you could lengthen a moment arm and use physics to have a more mechanical advantage when pressing, so the pressure would feel easier.

 

changing the leverage ratio to reduce pedal pressure will increase the stroke which is not a good idea. the very best solution for a heavy clutch would be to install something like a hydroboost slave which is like a powered system.

Link to comment
Share on other sites

Lengthening the clutch fork arm will make it easier to push the clutch pedal but then you won't be able to push the clutch pedal far enough to get the pressure plate to completely release the clutch disc.

 

You might try replacing your clutch assist spring, in case yours has weakened over the years.

 

 

“If you can't explain it simply, you don't understand it well enough.”

--Albert Einstein

 

Link to comment
Share on other sites

Well heck just go ahead and get a stair master exercise equipment and get in shape, lol.

How many times do you have to push the clutch in? If you are good you can change gears and not use the clutch.

David

When a man is in the woods and talks and no women are there is he still wrong??:P

David

Link to comment
Share on other sites

There is a mod that will work to decrease perceived effort. Put a larger pad on the clutch pedal- Not just the rubber cover, but the entire pedal. Find one on another car and cut it off (please don't do this to a forum members car) and weld it on to your pedal. Having more of your foot engaging the clutch will lessen the perceived effort. Another trick is to modify the seating position. Having your legs start off a bit higher will ease the pressure as well.

http://www.7173mustangs.com/gallery/1_01_07_15_8_53_18.png

 

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...