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rfuerst911sc
I am in the process of converting to 911 ebrakes. I have done a search and there is lot's of good info and pics. I have done the grinding to get the ebrake hardware to fit the 914 hub. I have it all mounted. I have fabbed and welded the stationary piece that the ebrakes have to stop against. However what I can't figure out from the pics is what are the rough dimensions of the transition/bell crank piece? I have moved the OEM cable mounts so I know where the cable will end and I have left room for the swing arm to do its thing but my head is stuck on this bellcrank. Can anyone give me the dimensions of the pieces they fabbed? And what did you use for raw stock? I am brain dead on figuring this out dry.gif
Aaron Cox
you can go 1:1 (arms are same distance from pivot) or a larger ratio (less clicks till full lock.)


i plan on 3/16 or maybe 1/4" plate for my arms.
Chuck
You may be far enough along in your fab work that this will not be helpful but, in the event that it is, I know Rich Johnson has an ebrake kit available. I don't know much more than that.
rfuerst911sc
QUOTE(Aaron Cox @ Oct 1 2007, 03:24 PM) *

you can go 1:1 (arms are same distance from pivot) or a larger ratio (less clicks till full lock.)


i plan on 3/16 or maybe 1/4" plate for my arms.

I agree on the 3/16 thick as that's what I think I'm going to use. I'm guessing each "leg" of the bellcrank will be aprox. 2 inches maybe 3 that's where I'm confused. I guess if I knew for sure where the pivot has to be the rest would fall into place. headbang.gif
ClayPerrine
Why use a bellcrank? Cables are cheap from the local boat shop.


iamchappy
I traced all of the parts i made and was going to send them to Aaron but have misplaced them. I may take it apart to clean up the paint over-spray from the paint job on my car that got on the control arms. If I cant find the other tracing i will retrace the parts again.
John
QUOTE(ClayPerrine @ Oct 1 2007, 05:19 PM) *

Why use a bellcrank? Cables are cheap from the local boat shop.


1. Because I already had 914-4 cables in good condition.
2. To keep replacement parts easy to source and off the shelf.
3. Because I can.


I would have to go measure mine to tell you the dimensions of my belcrank arms, but I believe that they are approximately 2" from the pivot.

Like Aaron mentioned, you could make a ratio out of the crank arm to minimize the e-brake lever travel, but mine are 1:1.

So Rich Johnson makes a kit for this? Maybe we should "oust" the ripoff (just kidding). If Rich makes a kit, I'm sure it is a good one, but I made mine myself. You could also do a web search for Phoenixhobbies.com

Good luck with it. They do work well.

rfuerst911sc
Iamchappy and John thanks for the pics. Iamchappy if you could give me the measurements I would really appreciate it. A template even better. Your pic clears up one question I had, I see how you built up the pivot point mount I was confused on that. And what are you guys useing for the link/rod assy to the ebrake butterfly actuater? I love this forum.
John
I used forged clevises from McMaster Carr and 1/4-28 socked head cap screws with jam nuts (for the adjustment). I also used male spherical washers under the heads of the fasteners (where they seat against the bow-ties) for any mis-alignment. I have been using them for more than a year now with no issues (after the initial adjustments).

I can look up part numbers if it would help you.

Once upon a time, I looked at "kits" but they would have been more money than I thought the typical CSOB would pay so I never made any "kits".

Good luck with your project.
iamchappy
I used i believe a 6mm threaded rod or whatever the clevis tapped for, i have a small castlated nut and washer and drilled a hole for a tiny cotterpin.

I measured the placement of all the brackets with the cables in place. My bellcrank arms are a little longer than some of the others ive seen so i could use the stock cables without extensions.

If you look at the bearing end you can see the needle bearing shaft pressed into place.

The brake caliper mount is for 951 brakes.
Aaron Cox
chappy - find your templates LOL

ill be doing this in the very near future.

i have a whole project folder saved with all of your pics and writeups.
John
Here are a couple other pictures
John
Here is the sketch that I made before changing them into triangular shapes.
PRS914-6
I did mine similar to John's. I moved the left side cable restraint back 1 1/2" and made an extension for the inner cable. As John originally pointed out, the cable will pull tight on the left side during suspension movement if it is not addressed like this or some other method to gain a little slack.
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ClayPerrine
The problem i have with a bellcrank is that you only pull ONE side of the spreaders. That makes the shoes contact the drum unevenly.

Rich, Wes, and I have been working on a way to use the stock cables and still retain the ability to use both spreaders, but it is not finished.
jim912928
Clay...count me in for a kit when you guys finish it. I already have all my parts (backing plate, shoes etc..). I like the thought of using original cables!
John
QUOTE(ClayPerrine @ Oct 2 2007, 05:43 AM) *

The problem i have with a bellcrank is that you only pull ONE side of the spreaders. That makes the shoes contact the drum unevenly.



No it does not make the shoes contact the drum unevenly. Who told you that?

On the 911 setup, the 911 cable sheath applies force to one spreader "bow-tie" and the cable itself pulls on the other spreader "bow-tie".

There is no real good way to support the 911 cables as they would run into exhaust if routed directly away from the e-brakes ala 911. This has been one of the major problems over the years when attempting to go 911 e-brakes.

The bell-crank is just a different approach and allows one to use factory 914 e-brake cables. It's a straight-forward simple solution.

Good luck. In the mean time, we will all be USING our e-brakes.
ClayPerrine
QUOTE(John @ Oct 2 2007, 04:04 PM) *

QUOTE(ClayPerrine @ Oct 2 2007, 05:43 AM) *

The problem i have with a bellcrank is that you only pull ONE side of the spreaders. That makes the shoes contact the drum unevenly.



No it does not make the shoes contact the drum unevenly. Who told you that?

On the 911 setup, the 911 cable sheath applies force to one spreader "bow-tie" and the cable itself pulls on the other spreader "bow-tie".

There is no real good way to support the 911 cables as they would run into exhaust if routed directly away from the e-brakes ala 911. This has been one of the major problems over the years when attempting to go 911 e-brakes.

The bell-crank is just a different approach and allows one to use factory 914 e-brake cables. It's a straight-forward simple solution.

Good luck. In the mean time, we will all be USING our e-brakes.



I have been using a 911 style e-brake for 2 years now. I am the one who came up with the idea of putting the backing plate on rotated 90 degrees downward. So I know a LITTLE bit about this subject.

And yes, it DOES pull unevenly. No one TOLD me that, I setup my park brake on my car 2 years ago and explored what you are doing now. I found that it needs BOTH spreaders to work properly.

But it is your car. Do what you want. You will hate it when that bellcrank gets crap clogged in the pivot and you can't get your park brake off. Wes Hildreth found this out on Mike Floyd's orange 74 2.0. Mike had to beat the bellcrank with a hammer to get it to release. This is not hearsay. I saw the results with my own eyes.

I would NOT use a bellcrank.
iamchappy
I use an oil bronze bushing as my pivot. I think design may have something to do with other bell crank setups not working properly. My pull is straight and short, I dont see any problems with binding but we will see...
I did consider the cable sheath design but didnt like the idea of the cables making that big U turn under the exhaust. A motorcycle throttle cable sheath with a 90 degree bend in the sheath maybe the cable answer to that.
ClayPerrine
QUOTE(iamchappy @ Oct 2 2007, 08:34 PM) *

I use an oil bronze bushing as my pivot. I think design may have something to do with other bell crank setups not working properly. My pull is straight and short, I dont see any problems with binding but we will see...
I did consider the cable sheath design but didnt like the idea of the cables making that big U turn under the exhaust. A motorcycle throttle cable sheath with a 90 degree bend in the sheath maybe the cable answer to that.



I have not burned a cable in 2 years of use.

But I agree, I don't like the cable that close to the exhaust either.

John
I too use oillite bronze bushing and washer in my design.

The GT car Miles Collier used to own also used only cables to actuate the e-brakes. The e-brake lever in that car was centrally located as well. The cables seemed to dangle quite low and run very close to the hot exhaust.

I saw the Collier car at Mid Ohio in the 80's and looked very carefully at the unique things that were on that car. That's when I really started learning about the unique features of certain 914s.

What were you saying about backing plates? (The pic is from the 80's)

Got any pictures?
Larry.Hubby
If you don't like the bell crank approach, you might be interested in the way I did it. I cut down two 911 parking brake cables, made special end fittings for them, and attached the outer ends to the stock 914 cables externally with the same clevis and pin that used to grab the caliper lever. You wind up with stock 914 cables, and stock 911 parking brakes (both bow-ties functional). The only special parts are the cut-down 911 cables, the end fittings for them, and the extra weld bracket to hold the outer end of the cut-down cables - five parts total per side, counting the cables. I've had it working on my car for a year and a half now, and it seems to work really well.

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iamchappy
That looks like a nice clean cable install. Good work!
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