[LaserDad]

For some reason, i just can't seem to stick to doing just enough to actually get my car running. My latest distraction is doing a hydraulic clutch conversion. I tried researching other people's solutions, but haven't found one that I liked.

As I usually do, I go for something that is close to our family. This time, I chose the PT Cruiser setup, since it's a 4 cylinder turbo. This is the master cylinder.

This is the slave cylinder. I like the throwout bearing design, over the push fork setup.

I have kept an old block around to test fit designs. I have an overhead winch that allows me to raise and lower the 555 tranny.

This was the stock setup that I wanted to replace.

Unfortunately, this slave cylinder is not going to work, because there isn't enough space for it between the housing and the clutch. The original is on the right.

I'll get into more detail in the next post.

 

[LaserDad]

This is how the stock setup looks.

I tried to find a center slave bearing that wasn't as long, but couldn't. That ruled out that option, so I was stuck trying to come up with a way to do a push type slave cylinder. Fortunately, I stumbled upon this YouTube video.

It shows a pull type slave cylinder setup. That gave me an easier option. I was going to get a Wilwood slave, but read a lot of negative reviews, so I went with a Howe setup from Summit.

It was pretty easy to mock up something that I think will work, without having to make any real mods.

The only real mod was to rotate the arm from the horizontal position. All that was required was to file a groove in the flat spot on the shaft, that orients the arm to the correct location.

If this project fails, I can always just put some weld on the groove to make it like original.

 

[LaserDad]

I thought that I could still use the PT Cruiser's clutch master cylinder, and mounted it through the floor. I just used a couple of plates for the pedal mock up. This was as far to the outside as there was room.

As the pedal is depressed, the slave's shaft pivots to stay somewhat straight. There was about 2 inches of travel.

After I came up with this, I learned that it would result in a harder pedal push, because it was too close to the pedal. For an easier push, I need to get it farther away, near the pedal's pivot point. I'm still not sure how I am going to do that, but found another issue.

The PT Cruiser master uses quick release fittings, not the threaded type that I want. That forces me to go with an aftermarket cylinder. Wilwood has a nice kit that includes reservoirs.

If I can find a way to mount it, it might keep this as an affordable setup. Another issue will be matching the master's bore size to get the pedal force and slave travel matched.

 

[LaserDad]

Since the PT Cruiser's setup will not work, I have purchased a Willwood universal master kit. It allows you to mount the fluid chamber onto the cylinder, or remotely, which I will need to do.

I mounted it through the firewall using nut certs, but had to mill out the upper side mount, to provide enough clearance for the top bolt head.

I also had to lengthen the push rod's threads, which are 5/16-24". This will allow me more adjustment at the pedal.

 

[LaserDad]

This is where things got hard. I spent most of 2 days making brackets and tweaking them. I started with a straight push setup, like with the PT Cruiser's master.

There are multiple issues with this, the worst being that the push rod can only travel 1-1/4", while the clutch pedal needs to travel 4 to 5". That rules out a straight type setup.

I came up with a cantilever setup which is similar to how a normal manual transmission linkage works. This is just a flimsy mockup, but it proves the concept. You can't see the lever's angle, but the pedal end is about inch higher than the pivot end.

With the pedal pushed all the way in, the rod is at the end of its travel.

This is not a practical design, even if I make it more robust. What might work is if I use rod ends for all three points of contact.

This setup would allow me to adjust the three points of the horizontal rod, up and down. Using nuts on the horizontal cross bolt could adjusted the positions of the vertical rod ends, to keep the vertical rods centered as the clutch pedal is pushed in.

I think this will work, but I'll have to experiment with various sizes. My goal is still to make this an easy conversion, but to also make it reversible. If anyone has any ideas, please let me know.

 

[LaserDad]

I made some progress today. I was able to get 3 rod ends, with 1/2" threads and holes. Since the threaded ends weren't long enough, I decided to drill them out to 5/16-24, the same as the slave cylinder's rod.

When the rod is fully compressed, the rod end's threads will just touch the cylinder body.

It took some tweaking, but I think I've got a viable solution. This shows the angle of the connecting rod with the pedals even.

With the clutch pedal fully compressed, the rod moves down and up toward the dash. This is caused by the rotation of the clutch pedal's arm, as it pushes down.

I realize that there's an elephant in the room. The linkage is under the brake pedal's arm, and will only allow it to depress about an inch.

I've come too far to let this be a game stopper. It will require cutting and welding the brake arm, but there's plenty of room for it. The down side is that it will require extra work that might keep others from doing this.

The next step will be to make a test stand to see if this master cylinder setup will move the slave cylinder far enough.

 

[LaserDad]

I've decided to scrap this pedal linkage workaround and go with a manual brake setup, which eliminates the master brake booster. This really opens things up and should make the hydraulic clutch conversion simple.

This will give plenty of room for a clutch master cylinder to mount next to the manual master cylinder. A huge bonus is that the linkage will mount at the proper height on the clutch pedal arm, instead of the make do setup that I was being forced into.

I've found some a nice Wilwood combo that looks great, and from this guy's YouTube videos, it sounds like it will perform well.

Wilwood Disc Brakes 14-0012 Summit Racing™ Master Cylinder and Pedal Pro Packs | Summit Racing

Free Shipping - Summit Racing™ Master Cylinder and Pedal Pro Packs with qualifying orders of $99. Shop Master Cylinder and Pedal Combos at Summit Racing.

www.summitracing.com

Of course this will require hours of research to figure out, but I feel like it will be more robust, and a simpler design.

I'm going to be doing the brake part on this thread:
www.turbododge.com/threads/manual-brake-conversion-g-body.1256756

 

[LaserDad]

Tom Allard did a hydraulic conversion on this thread, posts 241-264.
www.turbododge.com/threads/rear-wheel-drive-conversion-dodge-daytona.496681/page-13

 

[LaserDad]

I've made some major progress and am so glad that I don't have to make the rod end linkage work. Suffice it to say, if you want to convert to a hydraulic clutch, you will also need to convert to a manual brake master cylinder setup.

If you want to see more detail, go to the Manual Brake Conversion thread. These are some of the same pics that you will see there.

 

[LaserDad]

I decided to cut up the clutch pedal. It will still be reversible, but will require more work. Still, I don't think I'll need to go back to a cable type setup. The more I work on this, the more convinced I am that it will work.

I cut the plate off the back of the pedal, to allow the eyelet a place to mount.

I drilled a 1/2" hole for the eyelet bolt, but it might be a little higher than needed. The shaft hits the top of the opening, as it moves in.

To get around this, I could have moved the hole down to be more in line. Instead, I moved the top of the cylinder out 1/4". That changed the angle enough that the rod now moves freely.

I'll have to make a tapered spacer to mount the cylinder.

Another option might be to bend the push rod, but I'm going to try the tapered spacer, even though it will be more work.

I know that the pedal is a bit flimsy, so I'll need to beef it up a bit, but that shouldn't be difficult.

 

[LaserDad]

One of the clutch pedal mods is to replace the flimsy nylon bushings with oilite type. I'll have to shave the a little, but they will last much longer. I plan to add a spacer to encase them.

To test the slave cylinder's travel, I needed to connect a brake line from the master to the slave, which is 10ft away. I had a coil of 3/16" line handy, but it was coiled.

Doing a quick search on YouTube, I found this homemade tool, and built it.

www.youtube.com/watch?v=8BkXDwFj3PA

I like that it replaces the jaws of my vise, so you can fine tune the tension. Here's a link to the rollers on Amazon:

www.amazon.com/gp/product/B076V6H6GS/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

Including the bolts, I've got $20 into it.

 

[LaserDad]

I was able to test the pedal feel and slave cylinder's travel. Here's a ten second video of it:

The shaft should move 1-1/8" max, but it's only moving 3/4". Since the master is maxing out, it means that I will need to go to a larger size.

I did some searching and found that the slave has has in internal volume of 0.99 cuin.

Doing the math, my master has a volume of 0.53 cuin. I was able to find several Wilwood masters with larger bores, but they have shorter strokes. I would actually like to have a longer stroke. I finally settled on this one.

It has a volume slightly less than the slave's, but I prefer than, over having a larger volume, which might force more pressure into the slave, resulting in seal failure. At least I was able to keep the same stroke length.

If you don't want the entire kit, it sells for under $70 with just the one reservoir. It's supposed to arrive in two days, so we'll see if it works.

 

[LaserDad]

I don't know if anyone if following this, but can someone with a G-body measure how far the arm moves when you push the clutch to the floor? I'm trying to find out how much arm movement I will need, and my Laser is buried under a foot of snow.

 

[Glhs60]

Would a G body clutch arm travel be any different from any other TD??

Many put G body trans in L body's and don't have travel issues.

At least I don't remember any one having issues.

Thanks
Randy

 

[LaserDad]

I doubt it would be different, but don't know. I do know that the 520 & 555 are the same, so any of those would be fine.

 

[Glhs60]

My A-555 Omni is indoors so I could check the clutch lever travel.

Got a friend coming by tomorrow so he could help me check.

Clutch lever travel at the trans, correct??

Where the cable attaches.

Thanks
Randy

 

[LaserDad]

I would like to get the distance the arm moves, where the cable is.

 

[Glhs60]

Checked it today many times and came up with 1 and 3/16"

Is this close to what you were expecting?

Anything else feel free to ask!

Thanks
Randy

 

[LaserDad]

Checked it today many times and came up with 1 and 3/16"

Is this close to what you were expecting?

Anything else feel free to ask!

Thanks
Randy

Randy,
Thanks for doing this. It is exactly what I was looking for.

 

[Glhs60]

Right on !!!

Happy to be of any assistance.

Thanks
Randy