A mod of two e-brake mods

[BDHoneyman]

The mod described below is a combination of the e-brake mods by edwardb and carlewms. I started out planning to do just the mod by edwardb, to relocate the e-brake cables over the 4" transverse tube using pulleys. That mod was straightforward. However, the Lokar clevis hit the bottom of the e-brake bracket when the brake was engaged and, although that probably didn't have any practical effect on the integrity of the mechanism, the engineer in me didn't like it. So, I looked at the ratchet handle extension that carlewms did (his photo below):

carlewms.jpg

I didn't want to construct the entire handle so I opted to make handle extensions using soft steel bar (1/8" x 1/2") from McMaster-Carr. The goal was to move the clevis attachment pint another 1.5 in. from the ratchet pivot.

Extension pieces.JPG

The side view (below) shows the pieces attached. Note also the modification to the Lokar clevis: this is the same modification done by edwardb to widen the attachment area.

Side view.JPG

The photo looking down shows the attachment from another angle as well as the spacers I put in using the steel tubing. Note the angle of the extension bars achieved using a spacer at the ratchet handle attachment pivot point. I also needed to purchase a longer shoulder screw because of the added width due to the extension bars and washers.

Top view.JPG

The view from the transmission tunnel shows the set up in place. Now the clevis assembly doesn't hit the bottom of the e-brake bracket. An additional advantage is that the angle of the cable relative to the pulley is slightly less than without the extensions somewhat mitigating the rotational force on the pulley bolt when the brake is set.

On chassis.JPG

Here is a list of the parts used in the modification.

Lokar clevis: (Lok-S-8078)

Pulleys: McMaster-Carr (p/n: 3434T24)

A longer ‘shoulder screw’ for the pivot point: McMaster-Carr (p/n: 91259A622)

Steel tubing: 3/8” O.D., 1 ft. long; for spacer material (McMaster-Carr (p/n: 8910K393)

Steel stock: 1/8" Thick, 5/8" Wide, 1 ft. long; McMaster-Carr (p/n: 9922K15)

Various bolts, washers and nuts.

-Bruce

[AC Bill]

Looks good. Do you have the build to the point where you can test it?

[edwardb]

Nice work. That's one of the really cool things about this forum. Study ideas, build on them, and adapt them to your own build. Then pay forward to other builders. So, way to go, and nice documentation. I was very familiar with Carl's mod when I was working on mine. His mod was the one that steered me to the Lokar clevis and revising the path of the cables so they didn't go under the chassis tube. Just changed things up a bit with the pulleys. I was also thinking of doing the extended arms like he showed and you did as well. But the Wilwood e-brakes on that build (20th Anniversary Roadster #8674) literally only required the cable to be tightened to actuate. Little to no actual cable movement was needed. So the extended arms weren't needed. In fact made the e-brake handle have very little travel. So I lived with the clevis rubbing against the head of the carriage bolt. Has worked perfectly for the first driving season. I'm sure yours will work well also.

[SelectivePC]

Interesting, as i'm approaching my e brake install here shortly. May end up using this, we will need a short pull, easy lock up type e-brake. But worst case sericerio we will just run a seperate Hydro E-brake and second set of calipers on the rear.

[RJD]

Couldn’t tell from the pictures but did you have to modify the frame mounting bracket to allow for the greater width as a result of adding the arm extensions?

Thanks for posting - very timely as I’m reworking my e-brake now.

[BDHoneyman]

Hi, AC Bill,
The extension pieces are quite solid so the only uncertainty is the rigidity of the pulley 'arm'. The lever arm is relatively short so I think that the bolt will be sufficient over the long run-- I guess I'll find out. edwardb seems to have had a good experience with his setup and he has more operational time. I've mostly worked the mechanism to get out cable stretch. Carroll Smith ('Engineer to Win') cautions against lever arms like the one the pulleys are on and I may try to work up a bracket to hold the other end of the pulley bolt but, at this point, there isn't even a hint of give on the pulley bolt so I may just wait and see. It's amazing how long even simple mods seem to take. My wife has joked that by the time I get done with the car that I may be too old to drive.
-Bruce

[BDHoneyman]

Thank you. I'm continually inspired by the great work I find on the forum and I've certainly appreciated the detail you have in your build blogs.
-Bruce

[BDHoneyman]

Hi, RJD,

The photo, below, is looking down on the e-brake setup on the bracket. There is sufficient room for the bolts to clear:

Verticle bracket.JPG

Note, however, that I attached the e-brake as shown in the manual.

e-brake_2.jpg

Some builders have noted that attaching the e-brake in that way increases the interference of the handle with the cockpit aluminum side (I cut out some of the Al to make room for a bolt). A remedy for some has been to raise the e-brake handle by re-positioning the front 'L' bracket (i.e., the front and rear 'L' brackets would have the same positioning). If you did that, I think the extension arm bolts might hit the bracket.

-Bruce