Recommendations needed for a front drum to front disk conversion kit.

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I just took a re-look at my front disc brakes and they are the Wilwood brand, they went on very easy and instructions were great. For the booster, I bought the combo kit with the master cylinder, no surprises there as well, quality looked great and the instructions were well laid out and informative. My kit had the "stud" for moving the pivot point if reusing the non-power brake pedal. 

Tom

 
Thanks Tom.

Im doing a mixed install. A booster and master cylinder from Leedbrakes and local (Australian 1986 Falcon) front spindles and Girlock aluminium callipers. Mainly to enable getting new pads much easier than having to get them from the US when they wear out.

 
About the "pin" Do you have a local machine shop or know someone with a lathe? It would be very simple to make one. Just copy the original for size/length. The hard part is cross drilling the split pin hole, but that doesn't have to be dead on the center line. Material only needs to be CRS. It could either be weld in or made with a (3/8") thread, nut and lock washer.

 
Geoff, Yep, I have a local engineering company that can do the work for me. Just need to wait a week or so for them to clear other work before mine. It would take them no more than 30 min to do I would expect.

 
When I installed my front disc brake kit and brake booster, I used the original non-power brake pedal and drilled a hole at the 2 inch mark below and used a stud that came with the kit. Drilling the hole was not that hard, just use good drill bits. You may be able to find the new stud online at Leeds or another reputable parts store.  Good luck.

Tom
I installed a Leed Brakes conversion kit a couple of years ago. Had to drill the hole in the original pedal and use the supplied stud. I've had no issues at all.  I don't see the stud on their website but they may sell one separately. Give them, a call: 1-716-852-2139. 

Mike

 
Thanks Mike. Unfortunately the kit I got did not have the stud.

I have arranged for a local engineering company to add a stud as that will be quicker than ordering one from the US and getting it sent to Australia.

I will update once I get the pedal back.

 
Guys, 

Does anyone have the correct measurements for a 71-73 Mustang auto trans brake pedal for a car that has power assist brakes?

I'm after the measurements for the distance from the centre of the top pivot point to the centre of the pin that connects to the booster push rod.

Most information suggest that boosted brakes need a leverage ratio of 4:1. However, when I marked where the new pin needs to go on my non power assist pedal the distance works out to be 3:1.

I calculate that the pin needs to be approx 120mm or 4.724 inches centre to centre.

Here is a picture of my manual pedal.

 20211116_080735 (Large).jpg

Here is a picture of the pin area. Note the scratches in the pedal at about the 120mm mark. This is where I think the pin needs to go.

20211116_080740 (Large).jpg

When I compare this to a picture I found on the Cougarparts web page, it looks about correct.

brake pedal comparison.png

If any one has the measurements, I would appreciate it.

I have also emailed Cougar Parts to see if they can measure it for me.

If I was in the US I would just buy a second hand pedal. However, the cost of postage to Australia is more than the value of the pedal. So I may as well just modify the one I have.

 
I can't be 100% sure as I don't have an auto trans, but regardless, the booster is in the same place on the firewall. The push rod also ought to be in the same place relative to the booster center line. Therefore the dimension from the pivot centerline to the centerline of the new pin will also be the same, i.e. 2" below the old one. The ONLY thing I can see is your booster is NOT an original style 11" one. Even so, the push rod ought to be centered to the mount holes, I don't see your problem, your dimensions look to be correct.

Hope that helps clear up your issue. 

 
Geoff, Thanks for the info.

Re the booster, Yes Im aware that it is not the original style 11"one. I would have preferred that, but no one in Australia has got a 11" unit so settled for something that is similar.

Re the distance for the pin from the pivot point. Im just tripple checking before the modification is done. I was fairly sure I have the measurements right, but wanted to check. The old saying. "measure twice, cut once" comes to mind.

Thanks for your help.

 
Geoff, Thanks for the info.

Re the booster, Yes Im aware that it is not the original style 11"one. I would have preferred that, but no one in Australia has got a 11" unit so settled for something that is similar.

Re the distance for the pin from the pivot point. Im just tripple checking before the modification is done. I was fairly sure I have the measurements right, but wanted to check. The old saying. "measure twice, cut once" comes to mind.

Thanks for your help.
You're welcome. I tried to find the info I got for the placement of that pin, but I literally have folders stuffed with "stuff" and was unable to locate it. However, when I did mine, 2" work out about right, the push rod aligns as it should. It does NOT have to be within 10 thou!!! (inches that is) It will work out just fine. That said, it does NOT hurt to double check. You could even do a dummy install and mark the actual pin center directly off the push rod. Let us know how it all works out. 

PS; don't forget the correct adjustment on the push rod to M/C . 

 
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David,

Thanks for the info and thanks for checking.

I have completed a dummy install and marked the place on the pedal where it intersects the push rod. So all good.

As for the adjustment between the master cylinder and booster. It comes from Leed Brakes with the master cylinder connected to the booster. So that task is already done from the supplier.

 
 I changed my front drums to discs, using appropriate spindles. I have also changed my pedals as I am moving from an automatic to a manual gearbox. And the pedal support of a vehicle with drum brakes is different from a vehicle with disc brakes, which is important.

 
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