ECI c - body brake kit

ya the little brass pre-bent washers do go behind the brake arm pivot location, on the backside of where the horseshoe clip is...one side had one in, one side did not...

the rear brake job was a learning experience for sure. some things I can share:

1.) make sure you have the correct shoes. I had a large distraction while I was working, and didn't pay attention at a critical moment, and I put 2 long shoes on a side, and didn't realize it until that corner was totally reassembeled and back on the ground. I moved to the other side to start over there and only had 2 short shoes... so had to punt and totally undo what I just did to correct it.

2.) DO NOT DO THE STAR WHEEL FIRST. DO NOT DO THE BOTTOM SIDE FIRST. hook up the top side - meaning the primary spring...start up there. leave the star wheel and adjust spring assy until last.

3.) use your brake nail and its spring and keeper to hold the shoes while you are doing stuff.

4.) the secondary spring holds the parking brake cable guide in place. holy shite I lost a lot of time here with this guide and trying to do the star wheel first. I was trying to hold the cable guide in place with C clamps and stuff while trying to get the star wheel and adjuster assy in, , it was impossible. Once I learned that the secondary spring itself holds in the cable guide and to leave the star wheel until last, this became MUCH easier.
 
if you are old like me, go buy a brake spring tool. I got a universal spring tool and a brake nail tool both for $15 total, and it kicked the hell out of using vise grips only.
 
wow.. just wow. ever been kicked in the balls a bunch of times? . . .got up this morning, got the wife on the brake pedal,, bleeding away,,, the POS made in china reman wheel cylinder from oreilys bleeder screw shears off. I tell the wife to go inside.

pull the whole wheel apart again, go find another cylinder halfway across town, change it and put everything back.

bleed everything again.

go to start it, it goes rerw rerw rerw *click*
 
we're not hitchhiking anymore . . . WE'RE RIDING!

so,, saga continued,, I got it all together, and remember how autozone sold me the wrong shoes?? well, it was the wrong spring kit too.... the brake nails are about 1/4 longer.... and now I know what that means.

it means that when you test drive, the brake nails fall out and grind in the bottom of your drum. Worse, the shoes kick out and stick to the drum sides, pretty much making it impossible to take the drum off.

HOLY CRAP I HATE AUTOZONE.

I went up there and ragged on that guy. Tomorrow or Tuesday im getting ahold of his boss.

so I redid both sides. again. changed back to the old nails. primary and secondary springs appear to be the same, but the brake nails and their springs were for the 2 1/2" shoe size not the 2"..

so it feels really different with new front discs and rebuilt drums. its not as hard/firm as it was,, the pedal effort is overall easier and maybe travels down a bit more than before. but it freaking stops. pedal may be different b/c the change from stock dual drum MC to disc/drum MC - I have no idea what the stock bore was, but the MC I have on is 1 1/32 bore.
 
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... when I connected the vacuum hose the pedal went to the floor aplying the bake. To solve that problem I attached a spring on the brake pedal to pull it back up. It work fine, but something tell's me that I shouldn't need that spring.

Does anybody know anything about this issue?

You shouldn't need a spring on the pedal. There should be a spring in the MC that returns the piston. Where did you get the MC? You can check if the booster is OK by unbolting the MC and moving it forward. See if the booster follows the pedal motion. It should go out as a helper slightly pushes the pedal and return easy as you pull on the pedal. If that works, your booster is OK. The MC's piston should be fairly hard to push in against the spring. You might not be able to bend the tubes enough to try pushing on the piston with a screwdriver to check.
 
billgrissom - can you please elaborate on the location of the prop valve? why AFTER the distribution block? It seems that the rear brake line is just a pass-thru on the dist block? i.e. there is no distributing going on for the rear brakes at this location,, its looks like it just goes thru the block. The fronts look to be T split here 1 line in 2 lines out. But the back line looks like 1 line in, 1 line out.

I called ECI, and they anticipate that the rears are going to be doing next to nothing, and if i need a prop valve, its going to be to lessen the fronts to give the rears a chance...

i didnt expect that answer :)

they said try it how it is, and if needed squelch the fronts.

- - - im guessing that the prop valve is a cut-off pressure valve ? Like i hit 700 psi or lbs pressure or whatever and then i stay at 700 while the other side of the system continues to apply more pressure?

(the correct measurement is PSI . . . good ol interwebs . . .)

Funship32 answered correctly. For your rear's the "brake block" does not function as a "distribution block". The tube is routed thru the block for the pressure-imbalance check. The front and rear pressures out of the MC should be the same, which is what the switch checks, and lights the dash warning light if they don't. However, with disk-drum, you want less line pressure for the rear's, which is what the proportioning valve does, and why it must be after the imbalance switch. I think it acts exactly as it says, it reduces the pressure a fixed fraction. It does not stop at a fixed pressure like you guessed (a "pressure relief valve" would). ECI is crazy if they said the rears will do less braking, but that is "hearsay" to us. Anyone who says that has no understanding how drum brakes work. The have a "self-jamming" effect, which is why a small cylinder, or even an electromagnet, can give a strong braking effect. It is also why drum brakes are more sensitive to changes in coefficient of friction, even self-locking if something gummy gets on the shoes. A "metering valve" is used on the front caliper plumbing and time-delays the application of the front calipers to allow the rear shoes to contact the drum at about the same time as the calipers. It is part of the factory "combination valve" in ~1972+ cars. Pretty sure it is not essential. I didn't put one on my 60's cars. Maybe if you do circle-track racing you would want one.
 
Yes I'm shure I don't need a spring on the brake pedal, but that the way I found to make it work.(wrong way I know)
So Far after a lot of reading on the subject, I'm pretty shure that the brake booster doesn't come back far enough,(it doesn't come back to it's neutral position) so it's just like if I would aply pressure on the brake pedal all the time. Either the shaft from booster to MC is adjuted too short or the brake were not bled good enough.
I will unbolt the MC and apply pressure on the shaft coming out of the booster with the car running and see if it stay in, that will tell me if the shaft is adjuted too short. If I can keep in far enough, the booster should stay in to it's neutral position until I release the pressure just like if somebody would press on the brake. Then the booster should enmbark.
 
my brakes are DONE! if you need any help or have questions that I can help with about my drum to disc brake conversion or the rear brake drum rebuild, just let me know.

the rear wheel cylinders were oreily auto #WC78734 15/16 bore.
 
o ya,, i was sitting in the car today with the hood up,, and had my foot casually on the brake pedal. I guess I pushed the pedal some, but I saw the MC moving up in the engine compartment,, it was like "say that's not supposed to move" . ..

I go look at everything... the booster has 1 nut on it . .. . out of 4. holy jesus h Christ.

I put new lock nuts on there,,, the bottom inside one was stripped,,, no wonder there was not a nut on it...

anyway just another oh shite moment and something else to check
 
Hi,
I am trying to do my own conversion from drum to disk. Want to follow the ECI route since I have access to milling machine and can make the brackets.
I plan on re-using drum brake hubs and can machine them on a lathe to make the flange diameter smaller if needed.
I took all measurements and did some 3D modeling. In the end I came up with the rotor total height of 2 inches.
The problem I faced - I cannot find the right rotor. Does anyone know what rotor was used by ECI for their conversion kit?
Bolt pattern is not important since I can re-drill the holes.
 
I'll take a look the next time I'm at my garage but I'm pretty sure that it's an aftermarket rotor. If memory serves, it's drilled for multiple bolt patterns.
 
I can see that it has multiple bolt patterns and I was thinking that ECI could use a Chevy rotor and re-drill it.
What would you do if you ever need a replacement?
I will cal ECI tomorrow and ask about their rotors (not sure if they will disclose this information though).
 
billgrissom - can you please elaborate on the location of the prop valve? why AFTER the distribution block? It seems that the rear brake line is just a pass-thru on the dist block? i.e. there is no distributing going on for the rear brakes at this location,, its looks like it just goes thru the block. The fronts look to be T split here 1 line in 2 lines out. But the back line looks like 1 line in, 1 line out.

I called ECI, and they anticipate that the rears are going to be doing next to nothing, and if i need a prop valve, its going to be to lessen the fronts to give the rears a chance...

i didnt expect that answer :)
Sorry for the very late response. I just saw this. Perhaps someone else answered (didn't read all 12 pages). You are correct. You could mount the prop valve in the rear tubing, either upstream or downstream of the distribution block, since your car has separate F & R circuits (since ~1967). I was thinking of my 1965 car's distribution block, which is just a "quad T" with all ports connected. ECI's response is strange, and why you shouldn't take as gospel advice from whoever answers the phone. In a disk/drum car, you need to reduce pressure to the rear brakes, not the front like they say. If you don't, the rear drums will lock up the wheels much sooner than the fronts, which is very unsafe (rear slides around). Best to adjust the prop valve in a wet parking lot and keep skidding the tires and adjusting until the fronts lock up just before the rears.

The "metering valve" is on the front circuit. Its purpose is to hold-off the fronts until ~10 psi has built up. That gives the rear shoes time to move out to contact the drums. It is built into the "combination valve" of factory disk brake cars (1973+). The problem with using a combo valve is that it also has the prop valve and you can't adjust the ratio. You might be able to buy a separate metering valve. Without it, under hard braking, the fronts will grab first which tends to dive the nose of the car a bit. Not a big deal, and perhaps not noticeable if you have a stiff suspension (thicker torsion bars). BTW, disk calipers don't retract as much as drum shoes do. It is just the slight rotation of the square O-ring that retracts them, which is why dragging calipers are more a problem and warped rotors can sometimes be felt even when not braking.

Commando1 should give that rubber bushing to an A-body guy since many run manual brakes (for header clearance) and always need those things. You pop it onto the end of a manual brake pushrod, which has a groove to capture it. Then you push it into the MC. Once in, the rod won't come out without destroying the rubber (how would I know?).

Front disks are a good upgrade, but too many claim that front drums are unsafe or don't work. The strongest any brakes can be is enough to skid the tires. Does anyone truly think the factory 11"x3" front drums can't do that? There are other issues with uneven braking, and drums can be a bit more finicky, due to their "self-jamming" effect (why they need less pedal effort), but not much problem if well maintained. The biggest problem with drums is slower heat dissipation. They can absorb the energy of a single 80 mph stop, but then need more time to cool than disks. If constantly braking, like in road-course racing, or riding the brakes downhill (clueless Florida drivers in the Appalachians), drums can overheat and the shoes fade (melt). That is why the feds mandated front disks ~1973. Even then, rental drivers still were overheating front disks of GM cars on the Manua Loa descent on the Big Island. Every design has its limits. Studies have repeatedly found that the biological control element is the main limit in vehicle safety. One girl recently had the infamous "drive by wire" accelerator jam. She down-shifted to "2" (smart) and the car was then going safe and slower than traffic but she was concerned about how the engine sounded (high rpm), so she shifted back to "D" and proceeded to run into a barrier at high speed. In earlier decades we knew how to deal with a stuck accelerator (maybe turn off engine), which was not uncommon w/ a cable link.
 
I have been searching the DBA (Disk Brakes Australia) catalog for a few hours now. It has all makes and models with rotors dimensions. I have found a few different models with rotors that might fit. The closest rotor is for 94-99 Nissan Maxima. It is 11" diameter and 2" wide with working surface being 1" thick. And it has 5x4.5 bolt pattern. The funny thing is - my wife drives a 97 Maxima!!!!
I will go ahead and pull the rotor off her car and test fit it to my setup. This is a very rare occasion when Nissan is parked in the garage )))) But with the snow we had recently I will have to make room for it.
I will not bother with calling ECI for now.
 
superfragl,
Good plan on the Nissan parts. I have been working similarly towards cheap disks for my 1965 Dart, using the existing drum spindle & hub. That car has the rarer 5 x 4" bolt circle (though today's 5 x 100 mm is close/same). I will use 1965 Kelsey-Hayes rotors, but the drum hub is slightly larger than the mating flat on the rotor inside (concerns you mention). I have similarly been eyeing parts from my M-B and newer Chryslers to see what might fit on my 1960's Mopars (looks like M-B clutch fan fits). With enough people trying combinations, we may find many things that work. One A-body guy has re-purposed Volvo parts since he owns both. Chevy parts are cheap and forever, so the best source if browsing catalogs.
 
Nothing wrong with sourcing and engineering your own disc. But I must say that dollar for dollar the scarbird kit gets my vote and you don't have to break a ball joint, uses a ford Ltd one piece rotor to keep warpage down, and diameters out to almost 12 in, uses a 90s dodge ram caliper which are plentiful and have the ability to stop those overweight pigs pads from same available everywhere. The Chevy stuff used out there I believe usually comes from more mid sized type cars~1000lbs. Lighter than a c body. I have been looking into grafting Chevy trailblazer alum calipers all 4 and their steel racks onto my Charger. I'm not trying to stop you from looking just offering my 2 cents. Let us know what you find.
 
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