The Stovebolt Site Forums The Shop Area Driveline Brakes...to convert, or not to convert?

1950, 3100...

Last year, I rebuilt all my cylinders and my MC. Got everything working just fine. I've always had it in my head to do a disc brake conversion in the front when the time was right. I recently fired her up and when I backed out of the garage, foot all the way to the floor... I found where at my front right cylinder, all the fluid leaked out and bubbled the paint on the backing plate.

So maybe now is the time...but...

My brother in law says I'm going overboard and that I should just replace the MC, wheel cylinders and brake lines. I agree that will be more cost effective and will stop the truck as needed. I have long forgotten the notion of keeping eveything 'all original' because I am more interested in getting the truck to a more comfortable ride. With that in mind, I ultimately plan to swap for 3.55 gears, and either re-arch or replace the leaf springs, change shocks, add sway bars, etc...ad nauseum...So with all that in mind, I AM OK by doing the disc conversion, right?

Now, I need input/feedback on whether to go with the kit from CPP, or POL? What other parts, components or kits do I need to buy in addition to the full kit offered at the above retailers? I will be doing the whole kit with booster and all. Not counting the potential for new wheels, what specific modifications can I expect to make by doing this conversion? My truck is BONE STOCK and has no other frame or mechanical mods to date. I will be replacing ALL hard lines, and I have almost brand new flex hoses on the front.

Sure could use your input...

I agree w/ yer bro-in-law, if after renewing the system fluid leaked out of the connection at one cylinder, that's the fault of the mechanic, not the design of the brakes

spend as much as you like, but an old truck is an old truck and in good condition will drive, ride and stop as good as necessary, a complete chassis swap is the only way you'll "get the truck to a more comfortable ride" if you envision "comfort" in 2014 terms

Bill

It was MY experience with the CPP kit which I am not dissatisfied with, that it all went together as expected with a few glitches I didn't expect.

1) It uses 71-82 rotors and calipers. The special banjo bolts that I got were 10mm. They were too short for the thickness of the hose block. I ended up having to order longer ones from another vendor so they were safe to use. I HEAR they changed the calipers to 7/16. If you get 7/16 instead of metric, you might be alright.

2) I had the rotors drilled and slotted. You can ask for that, and BROTHERS (where I purchased the kit) were glad to accommodate.

3) The original drums are removed (talking about the front here) and I went ahead and purchased the aluminum hubs so I didn't have to remove rivets. I can sell the front hubs complete with the drums for more. It was easier that way. It comes with the proper wheel studs and everything you need.

4) I didn't go with the booster. The reason was if you want the booster, you get to decide how to modify or even remove your transmission crossmember to make it fit, OR you can put it on the firewall. Two problems.. Its not wise to remove the crossmember, and unless you are really good at changing this area so it all works, well, more expense and much more work. And, if you decide to put it on the firewall, the AD firewall was not made for this. So, you get to figure out how to beef up this area before installation.

Maybe someday I will regret not going to the trouble of adding the booster, but I am trying it without for the first attempt.

As far as why you are going to all this trouble in the first place.. if you haven't changed the engine or drivetrain, your max speed is about 55 mph. Your stock brakes are just fine for that. If your plan for the truck is to improve the high end to bring it to highway speed, then you need the dual master cylinder, prop valve, residual valves (2 pounds on the discs, 10 pounds on the drums), etc for safety.

Its a huge debate how far to take things. I am happy with the 261 engine, 55 1st rear end for open driveline, and Borg R10 overdrive to get me to about 70mph. To do that, safety belts, dual MC and front discs. Above that, whole nother world out there in the HiPo forum.

Lastly, to do this right, you need modern radial/front disc brake style rims. The ones back in the day were too thin and radials weren't on the radar. So, wheelsmith sells vintage style wheels with the modern radial widths. So, since you don't want two spares, 5 new rims are a good idea. Kaching!! But in my case, it was well worth it.

Can't say it better than Bill did above. I'm a daily driver only vehicle '49 with Huck brakes, single master resleeved in brass, stainless steel brake lines. I'm at 70-75 mph nearly every day and can lock up and stop with the best of brakes. How? Proper adjustment, inspection, yearly purging of all brake fluid, speed bleeders. I've never driven a disc brake version of our vintage truck. I have been told that the difference is in leg strength....power disc or drum vs manual drum or disc. I believe disc brakes were created to make it easier for mechanics, and more efficient for hard use racing (cooler braking) and lighter whole assembly.

You will need to plug into due diligence regarding periodic preventive maintenance whether you keep the drums or go with discs. IMHO, unless you go to a power disc or drum there will be NO DIFFERENCE in your pedal feel or stopping for that matter. I may go to a dual master cylinder in the future but in almost 18 years of driving feel no need to hurry to a false confidence, all my confidence is derived from a properly maintained brake system.

Post Script
Just this past week did my annual brake inspection, adjustment, brake fluid purging, wheel rotation, greasing of all the zerk fittings, repacking of the front wheel bearings. The four year old shoes are wearing perfectly.

Regards,

Cosmo

Will probably order 4 new wheel cylinders, a new MC, and re-run all new brake lines and bleeders. I can't argue with the experience y'all have to offer...that's why I'm here anyway.

Thanks again gents...

So next questions...suggestions on the hard brake lines?

1. Is stainless worth it on hard lines?
2. Pre-bent line kit? Or bend 'em myself?

I have seen some discussion here about copper nickel lines. I don't know anything about them but here is a thread on the subject. cu-ni lines

The copper nickel lines are suppose to be pretty nice.

I'll keep the drum brakes, but I think I'll change to a dual master cylinder.

John

I used the pre bent line in the rear . The one that runs over the axel

The others I bent myself, using brake line I bought from ebay. 25 ft roll
Easy to work with and easy to flair for a first timer.

I don't think there is a need for stainless

And this of course will happen again (truck without brakes) without proper maintenance. Your post gives one the impression that the brakes failed, ergo, I changed the brakes for the better.

Thanks again...y'all are doing so well I figured I'd throw you another'n...POL has a manual, DUAL reservoir master cylinder for drums that mounts in original spot on frame under the floor.

Given that I am not worried about dropping the few extra dollars, should I go on and install this dual MC?

If I do, do I also have to use an additional proportioning valve set-up? Their picture for this part shows a schematic with a prop. valve installed...

Fire away gentlemen...

Kinglonestar,
I would add to the positive opinions about copper nickel brake line. I had never done brake lines before I restored my 1950 COE. I replaced all lines, as well as the fuel line, and never had a failed flare or leak. You need a quality flare tool, but the alloy is more malleable than mild steel and easier to work with. I have never worked with stainless steel but I understand it is more brittle and it is easier to have cracked flares.

NAPA now carries it, although they won't likely have it in stock and will have to order it for you. It costs at least twice what regular steel line costs, but well worth it.

Kent

Truck apart? Do the dual, MUST BE Manual/Manual, NOT Disc front, Manual rear master cylinder.

Filling the new MC will be a little weird. The round hole in the cab floor isn't in the right place, but with a funnel with a tube may do the trick. Gotta think of everything involved.

Not sure if the MC is the controller of Manual vs Disc. If its the prop valve that is different, that would be much nicer since you can go to disc later without repurchasing the MC. If the MC is different, at least the special bracket is probably the same.

Autozone is also carrying the copper/nickel line. I picked up some a while back to redo some fuel lines, great stuff. If I ever have to redo any brake lines on my own vehicles, that's what I'm going to use (unfortunately, my customers will balk at the extra cost).
Just a note on Deve's suggestion on using a funnel to fill the master cylinder; Make sure you use a dedicated funnel for that. Only use it for whichever type of brake fluid you prefer, don't use it for anything else. That will eliminate any contamination issues.

I've seen these suggested before
...link...

Gonna stay old fashioned. Just ordered new wheel cylinders and master cylinder. Will get brake lines and tees, and SPEED BLEEDERS when the rest of the parts come in...figurin' a couple hours after that I'll be out cruisin again...

Just a suggestion to all,
In regards to filling the master cyl.
Why could,nt one RePurpose the Right side floor section from a junk or otherwise donor cab and move it over to the left side and get a second Battery Box cover!
regards,
steve sr.
ps
yes I know the park brake rod will prolly bisect the hole but who cares.

I just cut out the proper size for the new dual cylinder. Not that hard and less than half of the circle needed to be filled to do it. There is a nice stainless cover available from Brothers that makes it look great. All of that work is in my bolt bucket somewhere.

My CPP dual MC/booster kit came with the plastic squeeze bottle. It is very easy to fill with the bottle. I use an inspection mirror to determine the correct fluid height.

I enlarged the hole enough to get the cap out and covered it with a conduit box cover from the hardware store.

Getting ready to do the same. Where/what did you end up ordering?

I ordered 4 new wheel cylinders, and a new master cylinder from NAPA, all new steel, pre-bent brakeline kit from Eckler's, speed bleeder screws from Autozone. Just waiting on the master cylinder and then on the lift she goes...

I decided against the disc brake conversion after conversations with some sages from 'round here...

Is this the pre-bent brake line kit?

Pre bent line kit

Our truck was titled as a 1951 but has all the signs of being a 1952. These kits only go up to 1951. I wonder what the differences are? I've noticed some of the wheel cylinders etc also have differences with 1952.

There was a change over from Huck brakes to Bendix brakes. Wheel cylinders, MC and lines were changed. Use the VIN to get the right year for your truck if you still have the original on the door post. Use the shop manual to help identify what brake system you have. There are different parts for 1/2 ton and larger trucks so be sure you get the right bits.

CPP can be expensive. Check sites like Summit Racing. They might have the CPP parts cheaper. I got my booster for my 64 from them.

I used a roll of JEGS NiCopp Nickel Copper Brake Line, and it is really nice to work with. Bends and forms easily.