Well it appears that I made a huge mistake; I bought complete front and rear brake kits for mu ‘28 RPU without even considering that they might be wider than the stock hub/drum assembly. Turns out the add 1.5” to both sides. I do not have this mocked up yet but I can see where it’s headed. I am running full fenders an ‘35 wire wheels, I can’t afford 1/2” let alone 1 1/2”. What makes it even worse is that the only reason I gave up on disc’s was because of the width they would add. I still have the stock front axle although it has a Posie’s reverse eye lowering spring, I was going to see if I had room for a dropped axle when I got it mocked up. Maybe I can get a narrower axle for the front but I have no clue what to do about the rear. I still have the stock Model A axle although I was thinking about the possibility of swapping to a V8 axle in the future but that won’t help me with this problem. It seems that it is impossible to use the Lincoln brakes on a Model A with fenders and wider than stock wheels.
I'm involved in this. I was told by Boling Bros today when I asked the above question about width that kit added 1.5 inches to the width on each side. That's how the OP got his information, Neal I'm sending you the Boling reply.
This is the first I'm hearing, and I'm running the same front brakes I believe. And width is exactly what I expected. Where does the change come from? The width between backing plates? Or Wheel mounting surfaces?
Looking on the Boling Bros website at their Lincoln brake kit for Model As will show you far better pictures than I can provide. To be clear; these are 12’ x 2” Lincoln, Bendix style brakes NOT the ‘40 Ford Lockheed style brakes that have been used to put “juice brakes” on a Model A. Unfortunately, I already traded off my stock Model A spindles etc. so I have no way to compare and see where the difference in width comes from. Gary (Krylon) is doing his best to try and help me out but he has some other priorities (which I fully support) to deal with as well. I just took another look at the Boling Bros website and I don’t see anywhere on there stating that the brake kit will add 1 1/2” at each hub. It seems to me that it should. It never even crossed my mind that I should ask about that. I’m only posting this on here to see if other guys have had the same problem and if anyone has a suggestion for a solution. I don’t know if I can get a front axle that is narrow enough to solve the problem but I’m going to investigate that. What to do about the rear? I don’t have a clue. It seems to me that if you were to see a stock model A with stock wheels that sat an 1 1/2” farther out it would be very obvious and very strange looking. That doesn’t mean that it isn’t true however.
So I have a buddy that installed this set up on a '31 A, for someone that had purchased it. He said it made no sense to him and it added an inch and a half to both sides. He could find nothing on BB website about it but finally got ahold of someone there that verified it. He also said he had to do some machine work to get everything to go together. He also grumbled about the peddle ratio being wrong for the battery box mounted master cylinder. He checked into everything before performing the installation and discussed what it was going to do to the car with his customer, who is also running 16" '35 wheels. It put them at the edge of the fenders and looks "goofy" according to my buddy. He says the 1 3/4" Lincoln brake set up Boling Brothers makes does not add the width.... Hope this helps
Here's a Model A I built with Lincoln brakes, front and rear and '35 wires with 7.00x16-inch Excelsiors. Dropped axle up front, stock Model A rear out back with reversed eye main. No problems with fitment. More details can be found here..
Thank You for the pictures, they are encouraging and the article in the link is very helpful. My goal is very much the same as yours was.
Existing front axle is 50 1/2” - 51” On King Pin Centers so it looks like I can take care of the front by just throwing more money at it and buying a new axle. For the rear, I will just have to wait and see….
Sounds like the 1.75 wide set up is totally fine and the 2” option is the wide track problem maker? if so can you return them and get the narrower shoe option?
Huh? The backing plates and drums are the same whether 1.75 or 2” shoes. Just taking advantage of a little extra space in that drum. Shouldn’t make the wheel any farther out than a regular 40 Ford drum.
The set up uses BB brake drums and hubs...I believe that is where the dimensional difference is on how it is constructed. I don't know if it is fair to compare stock Ford part combinations to reproduced aftermarket parts....that isn't what the OP has Maybe he can share the measured dimensional differences against stock and see where it grows... except I understand he has gotten rid of the stock parts.... Edit: if engineering drawings were available for comparison....it would sure make things easier....but is that traditional
Ok. I was just under the assumption that since using 40-48 Ford drums/hubs on Lincoln backing plates was commonplace, the repro drums and hubs were the same dimensions. I do know for a fact that the Boling Brothers drums fit onto original 40 hubs. But maybe they have another set that will widen the track, just because? I’m sure that I don’t know their whole catalog.
I have no way of knowing what the measurement would be with the stock brakes but I measured the Lincoln brakes that I have and it is 4.25” from the back of the backing plate (where it mounts to the axle flange on the rear or the spindle on the front) to the face of the drum, the surface that the wheel mounts against.
@‘28 RPUSend your stock axle out to be dropped by someone such as Okie Joe or "He that shall not be named on this forum". That will narrow up the dimensions between kingpins, and you'd want a dropped axle for a hot rod, anyway. At the rear you're just adding 1/2" per Neal's measurement, so that shouldn't be a problem.
On the original 1941 Lincoln Brakes, the hub is mounted on the inside of the drum, on later years the hub is mounted on the outside of the drum, so that is the 1/2 " difference. Also with 41 Lincoln Drums you need 40 Ford wheels, the later 15" Ford wheels will not work unless you have the hubs on the outside of the drums eg: Boling Bros drums.
Thank you for that info Hemi. I’m using ‘35 16” wire wheels which will work on the Lincoln drums as long as a 1/8” thick support ring is used.
The width of the 1940-48 Ford drum is 3.75". It appears that the wheel bolt face of the Boling "Lincoln" drum is thicker than original Ford, and if the drum is 4.25" wide it will add 1" width per side compared to the original Model A drum.
We had this problem with our 4 banger A Sport Coupe. The BB Lincoln front brakes on 32-4 spindles on a stock Model A axle widened the track 1 1/2" per side. The 46-8 front brakes with the external hubs did the same. We had the original axle dropped 3 1/2" locally by Pages Chassis Works here in Australia. The dropping process doesn't stretch the axle. This process narrows the king pin to king pin measurement by 3" which returns the front wheel track to stock. Wheels and tyres are 16" 40 spoke KH with 500 x16s. At the rear the BB Lincoln brakes also widened the track by 1 1/2" per side. The 700x 16s on 40 spoke KHs are just under the fenders. I haven't been able to try it but in theory if you used the 1 3/4" rear brake shoes and a pair of 1935 rear drums you would only widen the track 1" per side. These drums don't require the spacer to use wire wheels. 1935 drums are the only earlier drums that fit a 1 3/4" shoe. 1932-4 use a 1 1/2" shoe. Phill
The measurement is the same between Lincoln and 40 brakes. They use the same hub. If you're using cast drums you may "lose" another 1/16" due to their additional thickness at the hub surface vs. original stamped drums.
You are measuring from the rear surface of the drum, which does not affect track width. The only measurement that matters is location of the drum surface on the hub relative to the kingpin. You could theoretically have a 5" deep drum and not affect the overall track width.
That's true. I mentioned this measurement because it's the same (3.75") as the genuine Lincoln 1939-48 rear drums.
The Boling Bros (formerly MT) cast drums mount to the outside of the hub, like the '40 Ford, which is why they require the "'40 Ford style" hubs both front and rear. Later Lincoln brakes mount the drum to the outside of the hub as well. In all practicality, though, the OE Lincoln hubs/drums are irrelevant since nobody uses them due to their scarcity. Essentially everyone is using the '40 Ford hubs with 1.75" Ford or aftermarket Lincoln drums with the '41 Lincoln depth OE or (more commonly) reproduction backing plates.
Thanks all for taking the time to join in the conversation. At this point it seems that in the front I will be using a drop axle. This is not a big deal because I was planning to do that in the future (if I had room under the fenders, I now know that I can) it just moves that expense up. I’m not sure about the rear though, it all comes down to tires. I am running a wider tire (radials) than those that have posted on here but I don’t know how much. I felt the fit was perfect with the stock brakes so I don’t know that I can afford an 1 1/2” without changing tires. The fact that I have radials may help due to the “corners” being “rounder” than bias ply’s. Hopefully I can mock this up in the next week or so and find out for certain. I have to say that with stock wheels and stock ride height the 1 1/2” wider would look awkward and silly, I doubt that I would do it.
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