The mock up caliper mount without the caliper.


The mock up caliper mount.



Here you can see the clearance between the wheel and caliper bracket, about 3/16".

I am starting a build thread for a front disc brake conversion that I am building for Nelson's ( nsboyd1210) 1950 F5 M-H. With the size of the M-H steering knuckle, spindle and hub, it is forcing a complete redesign of the conversion that I made for my '49 F4. I will be able to use the same '08-'16 Ford F450-F550 caliper assembly that I used on my truck, but I will be using a rotor from an '08-'12 IH 3300-4400 truck and school bus. The IH rotor is the same thickness in the pad area as the Ford rotor that I used, but the overall height is almost 2" shorter than the Ford rotor. Again with the size of the M-H parts I am unable to move the brake assembly back away from the wheel as far as I did on my F4, so wheel types will be more limited. So far the only wheels that I have that will clear the caliper and caliper bracket are the Budd/Ford lock ring wheels and the original widow makers. The 19.5" wheels that I used on my truck have too much dish in the wheel center to work. The widow makers have the least amount of dish giving the most clearance. The sectioned wheel in the photos is a Budd/Ford wheel dated 3-44. I also have wheels dated 7-36 and 4-64 and they have the exact same center profile as the one I sectioned. Ledge welded 22.5" wheels may also work, but I don't have one to test. Center welded 22.5" wheels have about the same dish as the 19.5"s, so they probably won't fit. The only modification that will be necessary to the M-H parts for this conversion is on the hub. The outside diameter of the hub will have to be reduced the width of the bevels to give enough room to install the bolts that will fasten the wheel spacer to the rotor mounting flange. All of the original parts can be reinstalled at any time. The photos posted are of the mock up bracket and rotor mount flange so I could check everything for clearance. I will try to keep this thread updated as I am able to get more done.
Thanks, Mark

 

Sure is an interesting conversion, of the original conversion. I agree that most 20" or 22.5" original wheels will have a similar center disc profile. Disc placement within the rim will differ, some significantly, but the discs will be similar. Some older wheels, 1930s era, will be much narrower and will have less dish in the disc. But that shouldn't be a issue for our era of trucks. Stu

 

Outstanding! Great to see someone tackle a modification like this....and for an obscure application as well. Your brake mod on your own truck turned out great, as I'm sure this one will.

 

Thanks for the reply Stu. I have 4 hub piloted Spoksteel 20" wheels that I had on the back of my '47 COE. I need to check the center profile of those against the Ford wheels. They probably have the same center profile as Spoksteel stud piloted wheels. Might be another option for Nelson, although probably harder to find.
Thanks again, Mark

 

Scott, Thank you for the kind words. This is the type of work I really enjoy doing.
Mark

 

I checked the template from the Budd/Ford wheels against one of the Spoksteel wheels that I have. There is quite a difference and they would give a lot more clearance between the wheel center and the caliper. The actual offset in the wheel center is the same as the Budd wheels, but the center has quite a bit more dish. I would imagine though that they would be very hard to find wheels.
Mark

 

Five lug x 8" pattern, hub piloted, Motor Wheel Spoksteel brand wheels were used by GMC and REO trucks during the 1940s and Studebaker R Series trucks of the early 1950s. Motor Wheel stamped their part numbers on the faces of the center discs between lug holes. Find yours and I should be able to look them up to tell you how much offset yours have. Stu

 

I know of a set of those 20" Studebaker stud piloted wheels........not sure if they are spokesteel. How many hand holes do they have or can you post a pic?
They are in a yard here locally, can check next time I'm there if you like.

 

Stu, I saw the numbers today. I'll get them tomorrow and post them. These wheels are off of a Reo truck. I took the hubs off of the Reo axle and bored the center hole in my Ford drums to fit the Reo hubs. I then installed them on the Eaton 2 speed I had in my '47 Ford COE so I could use the Spoksteel wheels.
Thank you, Mark

 

Scott, I will post a better photo of the wheel tomorrow. They have 8 hand holes. I think Nelson is needing more wheels, so we might be interested in them, especially if they are Spoksteel wheels.
Thank you, Mark

 

This is a Spoksteel hub piloted 5 x 8". Notice the lug holes look small. They are the same 3/4" as stud piloted, but are not champhered for the Budd style ball seat lug nuts. Hub piloted nuts have floating captive washers. Stu

 

Do those rotors have a 5x8 bolt pattern? Or am I not seeing something. I'm interested because I converted the f500 using the 5x5 1/2 pattern on the backside of the 2wd hub.

 

Phillip, The rotors have 10 holes on an 8.656" bolt circle. On the actual parts that will mount the rotor to the hub, the wheel spacer on the front will be larger and have approximately 30 5/16" bolts around the outside edge fastening the spacer to the rotor mounting flange on the back of the hub. The O.D. of the hub will have to be reduced slightly to allow room for the bolts.
I would love to see some photos and more details of your disc brake conversion.
Thanks, Mark

 

Stu, Here are the numbers from the wheels that I have; 81408 5 1/4 6 46
Is 6 46 the date of manufacture? It is also stamped Motor Wheel in two lines close to the numbers.
Mark

 

The 81408 is a 20" x 5" (or 7" using the old NWRA system). It has a Firestone RH style rim with continuous/unbroken side ring. I have record of it 1942 to 1949 at which time MW substituted number 82999. The 81408 has 5.25" offset (as your reading of the rim shows). That's actually a lot of offset for a 5" wide rim. The 82999 also has a 5" RH rim but has slightly less offset at 5.00" even. Stu