Now that I have your attention, yes they are cheap brakes, and they are big brakes, but they are not brakes with 13" rotors. Still interested, read on. What we have here is a simple, easy disc brake upgrade for you Mustang, Falcon, Fairlane, Ranchero, etc. It will work on any intermediate Ford V-8 drum brake spindle from about '63-'73. It uses two fabricated caliper brackets, two 11" Granada rotors, and here is the big part- two big GM calipers that have the 2 15/16" piston.
-Why the big GM calipers?
Unlike most disk brake swaps tha use the small GM metric calipers, this swap uses the same calipers that would have stopped a big Impala or even some 1/2 ton pickups. The "metric" calipers that alot of swaps use have a 2 1/2" piston, but the big GM calipers have a 2 15/16" piston that offers 12% more clamping force. The big calipers also use a brake pad with a bigger friction surface. The big GM calipers are also more rigid and will flex far less that the metric calipers.
There are three ways to increase braking force:
1. Increase rotor swept area via a larger diameter rotor.
2. Increase piston diameter or number of pistons for more clamping force.
3. Increase brake pad surface area.
We have two of the three covered, and I can tell you that this same system was in use on the front of my IMCA dirt modified for several seasons and and it will out stop a metric caliper system.
The rotors are common '75-'80 Ford Granada or Mercury Monarch. There were bought new at O'Reillys for $49.99 each:
The calipers are '75 Impala items that were $14.99 each at O'Reilly's. The brake pads cost $14.99 and were bought at AutoZone:
Here is a comparison between the metric and big GM brake pads, the metrics are on top:
We also used six 2" long x 3/8"-24 fine thread grade 8 bolts with steel locknuts to hold the caliper brackets to the spindles. The brake caliper bolts come with the new calipers. Cost $3.24:
Here are the 3/16" inverted flare to #4 adapter fittings that will allow the use of two 18" long stainless steel braided hoses. The adapter fitting connects to the stock brake line and fits in the stock bracket. Cost $9.99 a pair for the fittings and $9.99 a piece for the hoses:
We also used two 7/16"-20 to #4 banjo fittings that will allow the hose to connect to the caliper. Cost $6.99 each:
The brackets started out as common circle track weld on brackets that allow the big GM calipers on the rear ends of race cars. Cost $8.00 a piece:
The bottom of the brackets are cut off, and two holes are drilled to allow it to bolt to the spindle:
Six 3/4" O.D. x 7/8" long spacers are needed to space the brackets out. The spacers fit between the brackets and the spindle. A small "dog leg" brace is also needed to allow it to bolt to a third spindle hole:
Everything is bolted to the spindle and the dog leg brace is welded to the main caliper bracket between the arrows. Sharp viewers will notice that the brackets are in front of the rotors. The calipers are flipped backwards and swapped side for side on this system. Meaning the left caliper is on the right side and the right caliper is on the left side:
Here are the finished brackets:
The drum, hub and backing plate will need to be removed:
Clean any burrs off the spindle around the holes:
The brackets are bolted on using the grade 8 bolts:
The rotors are bolted on using new bearings and seals. I re-used the original '66 Falcon bearings as they were new and had zero miles on them:
Here is a shot of the brackets bolted on from behind:
The calipers are bolted on and the hoses are hooked up:
Here is a break down for the cost:
-Granada rotors-$49.99 x 2 = $99.98
-Big GM calipers-$14.99 x 2 = $29.98
-Brake pads- $14.99
-Brake adapter fittings - $9.99
-Caliper banjo fittings- $6.99 x 2 = $13.98
-#4 stainless steel braided lines- $9.99 x 2 =$19.98
-Brake caliper brackets- $8.00 x 2 = $16.00
-Total cost = $208.14.
I did machine my own spacers, and make the small dog leg brace, and that would add slightly to the cost to have someone do it for you, but it would still come in at far less than $300.00, and you end up with awesome stopping power. I also need to add that these calipers will clear 14" disc brake steel or aluminum wheels. I omitted the master cylinder installation as there are plenty of articles covering that sort of information, but I will tell you that I used a non power '75 Maverick M/C with a 15/16" bore and no proportioning valve of any kind. It stops awesome.