Disc brake conversion
 

I want to convert to front and rear disc brakes on my 51 f1. I am thinking of using the Speedway kit for the fronts and I am searching for a kit for the rears. Any help or suggestions is greatly appreciated.

Re: Disc brake conversion
 

Before someone tells you to go to the HAMB, try Google for "Rear Disc Brake Kits."

Re: Disc brake conversion
 

If you click on the "Hot Rods and Customs" forum it will take you to HAMB. You will be more likely to get your answer there.

Charlie Stephens

Re: Disc brake conversion
 

you might try www.ecihotrodbrakes.com.

Re: Disc brake conversion
 

I just finished installing an ECI kit on a 42 front axel. The problems were as follows. The Press fit was .004" and driving the bearing adapter with a piece of pipe with a BFH didn't work. So I warmed up the adapter with a torch and it went right on. The second problem came when I tried to install the bearing. The adapter had grown by .002" and ther wasn't any way to remove it so I spent an hour with some 80 grit emery bringing it down to size. Next problem was the filit radius of the adapter was too lard for the bearing and it wouldn't seat properly. I solved that problem with a small chain saw file to reduce the radius. This problem may have been caused by the Chinese bearings. I haven't solved the last problem yet and that's the seal doesn't fit the adapter, too small all these bearings and seals were bought new from the local parts store including the rotors. I still have the passenger side to do so Iturned the diam of the adapter down .002" and reduced the fillit radius to half the size. Still thnking about the seal.
Last but not least the Ford washer is too larg and has to be turned down, not sure how to do this yet. Now I have to find a grease seal.
I hope this doesn't deter anyone from installing disk brakes on your early ford.

Re: Disc brake conversion
 

Try the Wilwood catalog.
I have installed several of their kits and have them on my car.
The thing I like about them is, THEY FIT, right out of the box.
No machine work, heat or diddling with parts to get them to fit.
Their stuff looks like aero space quality also, not something made by kids in a tent in the middle of a rice paddy.

Re: Disc brake conversion
 

Eci 8608727046

Re: Disc brake conversion
 

I installed an ECI kit on my 46 Coupe, no problems what so ever.

Re: Disc brake conversion
 

Old Ron if you are having the same trouble as i did with the washer and it sounds like you are, Just go to advance, NAPA, Auto Zone and get one For newer car. I think about any will do, Plymouth, Falcon. Chevy. They do not cost much. Good luck Marv

Re: Disc brake conversion
 

I installed the ECI kit on my '49 front, only requiring a slight preheat of the adapter with a propane torch......Bob L

Re: Disc brake conversion
 

Same with my 36 with 42 squareback spindles.

Re: Disc brake conversion
 

It must be me then and my chinese bearings. I know one rthing that's fact, after driving on ther adapter you couldn't get the bearing on with out reducing the size of the adapter. I measures it and there was a .002 interface.

Re: Disc brake conversion
 

I used the ECI kit this past summer. Went on fine. I had to take the spindles down just a hair with emery cloth to get the adapter to slide on.

Not sure I'd bother converting to rear discs unless you're building a superfast street machine. I suppose you know that they don't make a disc kit for the stock F1 rear.

Re: Disc brake conversion
 

Going to discs in the rear is a lot of work and basically "overkill' on your old Ford. Put a power booster on your pedal assembly with the front discs and that will be all you need to stop on a dime.

Re: Disc brake conversion
 

I would imagine that with discs on the back of a pickup, you'd absolutely need a proportioning valve. To stop them locking up with an empty truck, maybe wound so far as to deem the discs no better than the drums.
Martin.

Re: Disc brake conversion
 

For those that used the conversion, are you sure the bearing was flush against the shoulder of the adapter. Probably wouldn' hurt if it didn't. Now that I think of it, I should have honed the inside of the adapter to the Ford spindle size. I tried driving it in with a 3 lb hand sledge and it just didn't want to go more than 1/2 way. ECI should make it the same size as the Ford bearing. I'm still not sure of the seal I bought and will go back to the auto store and check if I have the right one. I've been told the stock grese cap doesn't fit either. OH Well, learn sumpin every day.

Re: Disc brake conversion
 

I seem to remember in my kit that you had to remove a wheel bearing from the rotors provided in the kit and replace them with other wheel bearings/seals that were also included in the kit.

I remember looking hard at the adapter after I put it on the spindle to guarantee it was all the way on. There was just a little bit of space between the adapter and the shoulder, but it just wouldn't go on any further. Everything seems tight and I've put probably 100 miles on since the swap.

Re: Disc brake conversion
 

I was thinking along the same lines GM48. Ron, you bought Aspen rotors for the 4 1/2" BC, did you also buy wheel bearings and seals for same? I would think the outer bearings are OK, but the inners and possibly the inner bearing cones as GM48 suggests need to be swapped out for something different. The grease cap will need to match the rotor, and you might just reduce the diameter of the washer on your bench grinder. I'm sure Ralph Lisena, or one of his employees at ECI can advise on correct bearings/seals. Ralph is a great guy, and very helpful.

Re: Disc brake conversion
 

I just ordered the basic kit from ECI for my 1939 ford pickup. They told I can't use my original wheels any more with this conversion. Can any one please tell me what wheels I should be using. I have 5 1/2 lug pattern. Is it a newer ford model wheel?
thanks.

Re: Disc brake conversion
 

As ECI states in their listing - 73-93 Ford F100/F150

Re: Disc brake conversion
 

40 wheels work

Re: Disc brake conversion
 

For rear discs you need a modern rear end, say Ford 8 or 9 inch.

Re: Disc brake conversion
 

Rears are not necessary but a setup for the rear is easily fabricated if you have even basic skills.

Speedway doesn’t offer a kit for 5 on 5 ½ bolt pattern as far as I know.

Re: Disc brake conversion
 

Thanks . 51 merc

Re: Disc brake conversion
 

It has been a long time since I did the press fit of the bearing adapter but I remember I used a different technique, spindles in the freezer for a day, adapter slightly warm, pipe and BFH used as required.

Be aware that discs kits on the front usually move the wheel out about 1" per side. Could cause some interference on lowered front ends.

Rear discs are a waste of time and the associated emergency brake adjustment is a major PIA.

I get into a lot of arguments with my friends over this, so some should stand by to get pissed off. You want your front brakes to do 75% of the work. Therefore a proportioning valve is necessary no matter if you have discs or drums in the rear. If you look at new cars, the front discs are larger diameter (bigger moment lever) than the rears and that is how the 75% ratio is engineered in. But, aftermarket kits are usually all the same size so a proportioning or ratio valve is needed.

Drum brakes require less pressure than disc brakes because they are "self energizing", the shoes expand and get twisted into the anchor bolts or each other, depending on design, and a mechanical advantage results. Therefore in a disc/drum combo if you put the same pressure into the front or back, the rear brakes will lock up sooner. You need a proportioning valve to reduce the pressure to the rear drums.

Now having typed out the diatribe let me say that I am not an engineer but a guy who did a technical paper on disc brakes back in college when dinosaurs roamed the earth. FWIW.

I'll leave it to someone else to point out why residual pressure valves are different but also a good idea to incorporate into your old Ford brake system.

Re: Disc brake conversion
 

"Therefore a proportioning valve is necessary no matter if you have discs or drums in the rear. If you look at new cars, the front discs are larger diameter (bigger moment lever) than the rears and that is how the 75% ratio is engineered in. But, aftermarket kits are usually all the same size so a proportioning or ratio valve is needed."

Not necessarily. The Wilwood pedal assembly has a mechanical proportioning system built in. You can change the front rear bias in less than a minute.

Re: Disc brake conversion
 

Why do we want disc brakes? Not trying to be a smart a**, just wondering what a good reason is.
And, if we do want them, why on the rear? Seems like a waste, except if you have something like a 9-inch. Then they become a 'safety feature', because they hold the wheel, tire, axle 'IN', when (not if) the axle bearing fails, and the axle and wheel assembly wants to take off down the bank. (Been there, done that)
I haven't seen mention of a power booster. When adding disc's to an early Ford, is it generally accepted that a power booster be added, or not necessary?
(Reason for asking, I have one factory produced vehicle that has front disc's, drum rears, and NO factory power booster. It takes a LOT of pedal force.)
Thanks for a good thread.

Re: Disc brake conversion
 

ECI, talk to Ralph, he has the answer to your questions.
Have their disc brakes on my 41 pickup, no power booster.
Lincoln brakes on original rear end. eleven in F-150 rotors
no proportioning valve. Works great, stops on a dime.

Re: Disc brake conversion
 

Yo 41, it never rains in So. Cal, right? And if it does or you run down the road and come upon a fire hydrant flooding the street with kids running out to play in the water and you do a panic stop, are you gonna swap ends? The way you test or adjust prop. valves is to find some place dusty or slippery (loose traction) to see how the rig stops then.

And Pete, the Wilwood has a "mechanical proportioning system built in" but it's still a prop. valve, right?

Don't take my questions as being ornery or confrontational. Just asking.

Size of the master cylinder piston determines power assist needed or not. I have 4 wheel discs on my '36 pickup with 15/16" m/c piston. It does the job fine. My regrets have been the e'brake adjustment and in hindsight to other old cars I have upgraded, the rear discs are not worth the effort.

Re: Disc brake conversion
 

Another problem with the rear disc is what are going to use for a emergency brake. Calipers can be a pain in the ass. With rear shoes theirs no problem installing and bleeding

Re: Disc brake conversion
 

"And Pete, the Wilwood has a "mechanical proportioning system built in" but it's still a prop. valve, right?"

Roger on that and it really works keen. Does the same job as a valve but without the extra plumbing. Saves a couple of pounds which is important in race cars.

Re: Disc brake conversion
 

If you use Wilwood's they have a mechanical single puck calipers that bolt right on and use the stock cables.

By the way, I don't work for Wilwood but I use their stuff on most brake conversions because it bolts on with NO machine work or mods required.