E brake with disc conversion?
#106
11-18-2010, 08:20 PM
This is what I have found: With the chevy rotors I had to grind the pads just to get them on. Now they are tight enough to drag on the rotors, w/o adjusting the ebrake lever nut/rod. When I do try to tighten the lever nut, so that the ebrake will actually hold the vehicle, the pads are locked against the rotors. Surely I'm not supposed to drive like that. It would fry something.
I have adjusted the cable up and down until I'm sick of the flaming thing, and still the ebrake is undectable when the vehicle is rolling!
I will try to clamp the brakes and adjust while pressed, and see if that makes any difference. By this time I'm really impressed with the Caddy calipers...kind of like the daughter's boyfriend, but I can't throw him away.
I have adjusted the cable up and down until I'm sick of the flaming thing, and still the ebrake is undectable when the vehicle is rolling!
I will try to clamp the brakes and adjust while pressed, and see if that makes any difference. By this time I'm really impressed with the Caddy calipers...kind of like the daughter's boyfriend, but I can't throw him away.
#107
11-18-2010, 09:16 PM
Obviously this system worked well enough to meet the safety standards as installed in the Caddy, which I think means it has to hold on a grade of at least 10%. While that Caddy is a little lighter and has smaller wheels this thing should still work at least fairly well. The standard is for the pressure a woman who weighs about 100 lbs. can exert on the pedal/lever. We know this force multiplied through the linkage should be about 20 to 1 or so (assuming brake lever travels 20" from after slack is taken up to end of travel after full force is applied divided by about 1" effective travel of the caliper lever) when minus friction losses. This also assumes the forces are being applied at proper angles.
You show a pic on page 7 of the installed caliper with the emergence brake off. What would this look like with the brake fully on? A couple more ideas:
Is it possible that the geometry of the emergency brake lever on the caliper and the tab holding the cable to the axle is such that it isn't applying force effectively? You would want to check this with the brake on of course.
Is it possible that the angle of the tab you welded to the housing is binding at the housing end so you're losing too much force to friction and the cable can't pull hard enough on the lever? How about the rest of your cable system, is it all OK?
I hope this works, I want to buy your old brakes from you!
You show a pic on page 7 of the installed caliper with the emergence brake off. What would this look like with the brake fully on? A couple more ideas:
Is it possible that the geometry of the emergency brake lever on the caliper and the tab holding the cable to the axle is such that it isn't applying force effectively? You would want to check this with the brake on of course.
Is it possible that the angle of the tab you welded to the housing is binding at the housing end so you're losing too much force to friction and the cable can't pull hard enough on the lever? How about the rest of your cable system, is it all OK?
I hope this works, I want to buy your old brakes from you!
#108
11-19-2010, 08:24 AM
Senior User
Join Date: Nov 2010
Location: Chesapeake Va.
Posts: 373
Likes: 0
Received 0 Likes
on
0 Posts
My 2 cents if you don't mind, Im building a 1976 Hi-boy and am at the point of installing my disk brake conversion. I am using 85 rotors had to have them turned 4 thousands off each side to obtain the proper clearances (caddy rotors are 1.21 and the blazer rotors are 1.295) Caddy e-brake calipers and pads.
As a side not somewhere in your write up you mentioned your calipers were the same sided but I wanted to tell you mine are a Right ad Left HOWEVER what I was able to do was turn my brackets so that the drivers side was at 10 o'clock and passenger side at 2 o'clock. This is letting me use the cable brackets off of the 1979 calipers (since the 1977 calipers dont come with brackets) and lets the cables pull up towards the frame in a natural relaxed position. Note: The calipers have to have one hole drilled for the bracket bolt.
Anyway back to some help, I have spoke to someone named Mark, very informative and easy to talk to, at I believe they are called ECI The number is 1-860-872-7046 but what I got from him was that our masters could have a RESIDUAL VALVE in them for the rears (this is determined by sticking a paper clip in the fitting if there is resistance you have one) if not it is in the proportioning valve. His input was to take the RESIDUAL VALVE out of the proportional so that there is proper flow to the rear calipers.
The residual was in there for our rear wheel cylinders to keep the tension from the rear shoe springs from collapsing the dust boots and plungers thus allowing air into the lines. The way the master works for our trucks is that the rears actuate slightly at first depression of the pedal then the fronts that do 75% of the stopping then full engagement of the rears so with that I dont believe you are getting that first impact of the rear calipers with proper flow and pressure.
REMEMBER THIS IS JUST MY 2 CENTS
Up to the front, 1978 F-350 booster mounted to the firewall pivot bracket, all rods line up, and 1979 master cylinder that bolts directly to the booster no modifying required.
I read all of your credentials and am not doubting your abilities but have you gone thru all of the basic steps from the start, its the simple ones we forget when we are this involved and pissed off, I am refering to bench bleeding the master, starting farthest away from the master and having someone listen to your every direction while bleeding as in not pumping the pedal to fast and holding till your bleeders are tightened.
Hope something here helps
Let the blasting, bashing and criticism begin!!!
As a side not somewhere in your write up you mentioned your calipers were the same sided but I wanted to tell you mine are a Right ad Left HOWEVER what I was able to do was turn my brackets so that the drivers side was at 10 o'clock and passenger side at 2 o'clock. This is letting me use the cable brackets off of the 1979 calipers (since the 1977 calipers dont come with brackets) and lets the cables pull up towards the frame in a natural relaxed position. Note: The calipers have to have one hole drilled for the bracket bolt.
Anyway back to some help, I have spoke to someone named Mark, very informative and easy to talk to, at I believe they are called ECI The number is 1-860-872-7046 but what I got from him was that our masters could have a RESIDUAL VALVE in them for the rears (this is determined by sticking a paper clip in the fitting if there is resistance you have one) if not it is in the proportioning valve. His input was to take the RESIDUAL VALVE out of the proportional so that there is proper flow to the rear calipers.
The residual was in there for our rear wheel cylinders to keep the tension from the rear shoe springs from collapsing the dust boots and plungers thus allowing air into the lines. The way the master works for our trucks is that the rears actuate slightly at first depression of the pedal then the fronts that do 75% of the stopping then full engagement of the rears so with that I dont believe you are getting that first impact of the rear calipers with proper flow and pressure.
REMEMBER THIS IS JUST MY 2 CENTS
Up to the front, 1978 F-350 booster mounted to the firewall pivot bracket, all rods line up, and 1979 master cylinder that bolts directly to the booster no modifying required.
I read all of your credentials and am not doubting your abilities but have you gone thru all of the basic steps from the start, its the simple ones we forget when we are this involved and pissed off, I am refering to bench bleeding the master, starting farthest away from the master and having someone listen to your every direction while bleeding as in not pumping the pedal to fast and holding till your bleeders are tightened.
Hope something here helps
Let the blasting, bashing and criticism begin!!!
#109
11-19-2010, 08:27 AM
Senior User
Join Date: Nov 2010
Location: Chesapeake Va.
Posts: 373
Likes: 0
Received 0 Likes
on
0 Posts
#110
11-19-2010, 12:36 PM
Hi, what is the part # for the swaglok you bought ?
I've thought of the caddy calipers for my disc setup but also read they are not so great especially with bigger tires.
What are you guys running for line locks. electric ones are junk as you cant leave them on for long periods of time. I went with a mechanical ball valve style one made by swagelok. Its high quality and holds for on any hill.
Benefits of this are:
Uses your brake pressure to hold and in my case with hydoboost brakes you can apply a ton of pressure to it,twist the valve and it will hold on the steepest hill you can put it on good for offroad.
The other thing I love is with my manual transmission starting on a steep hill wheeling can cause you to have to roll back while jumping to gas from brake. All I do now is put on the line lock give it some gas, slowly release clutch and line lock at same time and it just jumps stright ahead with no roll back!
The other trick I use it for (and was one of my biggest reasons for it) was again while offroad I can engage it on my back tires locking up solid and with my twin stick t case I can engage the front axle in front wheel drive only and with my hydro assist steering crank tires all the way to one side on a tight corner and just dig the front tires, pivoting of the backs and turn on a dime. Wouldnt really suggest doing this one on 44's though unless you beef up the front end as I run a 79 dana 60 front with 5:13's detroit locker, 35 spline chromoly inner axles and warn premium hubs
Basically these mechanical locks are pretty nice I actually researched it quite abit before finding this one and found that jamar mechanical line locks are junk and dont hold well while these are high quality and ver y small and compact just plumbed into your rear brake system. I mounted mine at the base of my steering column on the removeable panel for ease of install to plumb lines and I highly suggest putting it there and its pretty much in line with your master cylinder. Another trick is to put brass 90degree fittings right on the valve to plumb lines straight back instead of what a gradual radius brake line would give you...
o yeah part # B-42f2 for a brass one (55-60$ what I paid CND)
or S-42f2 for stainless pricey if you want it
you guys in the states could probably find them cheaper I'm sure
O and my lines dont come "straight" out to through the fire wall to master I actually have one more trick where it then plumbs over behind dash to my adjustable proportioning valve. Basically with my hydrboost brakes running off my modified and drilled pressure tested at 1500 psi saginaw powersteering pump it creates so much power to rear discs that I had to tune it down to the right front to rear bias without lockup. I could travel at about 50 km/h and lock up 44's when pressing pedal hard. To fix it I plumbed in a wilwood adjustable proportioning valve that was originally under the hound and fine tuned it down until rears only were just on the verge of locking. This time arounf with my new cab I figured what the hell I'll mount it on my dash so I couls twist dial up real fast while driving and use it to powerslide to a stop or around corners. It will also be funny to scare the crap out of people skidding to a stop making a loud 44" howl...lol I figured why not I like to have full control of everything on my truck.
What are you guys running for line locks. electric ones are junk as you cant leave them on for long periods of time. I went with a mechanical ball valve style one made by swagelok. Its high quality and holds for on any hill.
Benefits of this are:
Uses your brake pressure to hold and in my case with hydoboost brakes you can apply a ton of pressure to it,twist the valve and it will hold on the steepest hill you can put it on good for offroad.
The other thing I love is with my manual transmission starting on a steep hill wheeling can cause you to have to roll back while jumping to gas from brake. All I do now is put on the line lock give it some gas, slowly release clutch and line lock at same time and it just jumps stright ahead with no roll back!
The other trick I use it for (and was one of my biggest reasons for it) was again while offroad I can engage it on my back tires locking up solid and with my twin stick t case I can engage the front axle in front wheel drive only and with my hydro assist steering crank tires all the way to one side on a tight corner and just dig the front tires, pivoting of the backs and turn on a dime. Wouldnt really suggest doing this one on 44's though unless you beef up the front end as I run a 79 dana 60 front with 5:13's detroit locker, 35 spline chromoly inner axles and warn premium hubs
Basically these mechanical locks are pretty nice I actually researched it quite abit before finding this one and found that jamar mechanical line locks are junk and dont hold well while these are high quality and ver y small and compact just plumbed into your rear brake system. I mounted mine at the base of my steering column on the removeable panel for ease of install to plumb lines and I highly suggest putting it there and its pretty much in line with your master cylinder. Another trick is to put brass 90degree fittings right on the valve to plumb lines straight back instead of what a gradual radius brake line would give you...
o yeah part # B-42f2 for a brass one (55-60$ what I paid CND)
or S-42f2 for stainless pricey if you want it
you guys in the states could probably find them cheaper I'm sure
O and my lines dont come "straight" out to through the fire wall to master I actually have one more trick where it then plumbs over behind dash to my adjustable proportioning valve. Basically with my hydrboost brakes running off my modified and drilled pressure tested at 1500 psi saginaw powersteering pump it creates so much power to rear discs that I had to tune it down to the right front to rear bias without lockup. I could travel at about 50 km/h and lock up 44's when pressing pedal hard. To fix it I plumbed in a wilwood adjustable proportioning valve that was originally under the hound and fine tuned it down until rears only were just on the verge of locking. This time arounf with my new cab I figured what the hell I'll mount it on my dash so I couls twist dial up real fast while driving and use it to powerslide to a stop or around corners. It will also be funny to scare the crap out of people skidding to a stop making a loud 44" howl...lol I figured why not I like to have full control of everything on my truck.
#111
11-20-2010, 09:48 AM
All I've ever read on the intardnet is how the eldorado calipers suck as parking brakes. Well, they don't.
I recently bought and installed the TSM eldorado calipers (because they're brand new and include the parking hardware). Mounted both behind the axle, bleeders up and adjusted per the online directions. Reused the stock parking cables (both of mine are the same length - buy a drivers cable for the pass side). Had to adjust the cable tension according to the shop manual to get 70-80 lbs when taught. <-- Most people don't do this step, which is why the parking pedal may seem too hard or too soft.
Haven't used the parking brakes offroad, but the eldorado calipers work perfectly well in my driveway (~8% slope).
Only other option is a driveline brake, but that's $400 & maybe a new driveshaft ($350).
I recently bought and installed the TSM eldorado calipers (because they're brand new and include the parking hardware). Mounted both behind the axle, bleeders up and adjusted per the online directions. Reused the stock parking cables (both of mine are the same length - buy a drivers cable for the pass side). Had to adjust the cable tension according to the shop manual to get 70-80 lbs when taught. <-- Most people don't do this step, which is why the parking pedal may seem too hard or too soft.
Haven't used the parking brakes offroad, but the eldorado calipers work perfectly well in my driveway (~8% slope).
Only other option is a driveline brake, but that's $400 & maybe a new driveshaft ($350).
#113
11-20-2010, 02:05 PM
#114
11-20-2010, 02:27 PM
[quote=unreng;9582212]All I've ever read on the intardnet is how the eldorado calipers suck as parking brakes. Well, they don't.
I recently bought and installed the TSM eldorado calipers
I'm glad they worked for you. However, you did not use Caddy calipers. You used TSM calipers, manufactured for TSM, specifically for the conversion, not Caddy calipers.
Another thing: unless you used the TSM adapters, or you have a bronco, the 73--78 F series trucks ebrakes do not fit the Caddy ebrake brackets. Period.
I recently bought and installed the TSM eldorado calipers
I'm glad they worked for you. However, you did not use Caddy calipers. You used TSM calipers, manufactured for TSM, specifically for the conversion, not Caddy calipers.
Another thing: unless you used the TSM adapters, or you have a bronco, the 73--78 F series trucks ebrakes do not fit the Caddy ebrake brackets. Period.
#115
11-20-2010, 11:24 PM
So this is about using an authentic "Caddy" caliper vs. using a caliper that will work and has identical dimensions?
The only modification performed to the OEM parking brake cables was to remove the spring. And the TSM brackets look virtually identical to 79-85 caliper brackets (and identical to the brackets you're using).
.jpg)
For $320 I have a pair of calipers that plugs and plays without modification. To me it's money well spent for a required vehicle safety item.
More time was spent painting the calipers (and the drying time) than the install.
The only modification performed to the OEM parking brake cables was to remove the spring. And the TSM brackets look virtually identical to 79-85 caliper brackets (and identical to the brackets you're using).
For $320 I have a pair of calipers that plugs and plays without modification. To me it's money well spent for a required vehicle safety item.
More time was spent painting the calipers (and the drying time) than the install.
#116
11-22-2010, 09:48 AM
I was merely pointing out that what you used is not Caddy calipers. They are TSM calipers, taken from the GM design, and re engineered. The one on your driver's side does not exist with the GM calipers, because GM did not make a left and right. They made one caliper, and only changed the direction the ebrake lever turns, so that one cal. is installed in front, and one behind the axle. I also read that TSM calipers open to 1.30" to fit the Chevy rotors. That means they used a shorter piston.
All in all, you have a better system. Had I known all this beforehand, I certainly would have used the TSM system as well.
The oem ebrake cables for the 73-78 p/u's will have about 4'' space between the housing and the bracket on the caliper, when converting to disc from drum. If you don't have that, and you have that year truck, then your cables have been changed or modified. Either way, it worked out great. Enjoy.
All in all, you have a better system. Had I known all this beforehand, I certainly would have used the TSM system as well.
The oem ebrake cables for the 73-78 p/u's will have about 4'' space between the housing and the bracket on the caliper, when converting to disc from drum. If you don't have that, and you have that year truck, then your cables have been changed or modified. Either way, it worked out great. Enjoy.
#117
11-25-2010, 01:14 PM
After reading other members comments, I realized I have a problem with the ebrake cables. This fabricating is relatively new to me, and after thinking over my 'system', I can see that my cables are awkward, attached in a binding fashion. I thought I did good with the install, but now I'm convinced that is why the ebrake is functioning properly: the cables are binding, creating to much friction for them to pull enough.
I am going to remove the caliper which sits in front of the wheel, and take it apart. Then I will drill and tap a new bleeder hole so that it can be installed behind the axle without the bleeder being down. Mounted that way, both cables will attach from the same position.
I noticed in Ureng's post that his brackets are different from mine too. Mine are from Greatlakes offroad, and they have the caliper mounted at a 45 degree position. With his the caliper sits nearly straight up and down like the caddy oem, thus placing the bleeder at exactly the needed position.
I am going to remove the caliper which sits in front of the wheel, and take it apart. Then I will drill and tap a new bleeder hole so that it can be installed behind the axle without the bleeder being down. Mounted that way, both cables will attach from the same position.
I noticed in Ureng's post that his brackets are different from mine too. Mine are from Greatlakes offroad, and they have the caliper mounted at a 45 degree position. With his the caliper sits nearly straight up and down like the caddy oem, thus placing the bleeder at exactly the needed position.
#118
05-21-2011, 10:29 PM
So this is about using an authentic "Caddy" caliper vs. using a caliper that will work and has identical dimensions?
The only modification performed to the OEM parking brake cables was to remove the spring. And the TSM brackets look virtually identical to 79-85 caliper brackets (and identical to the brackets you're using).
For $320 I have a pair of calipers that plugs and plays without modification. To me it's money well spent for a required vehicle safety item.
More time was spent painting the calipers (and the drying time) than the install.
The only modification performed to the OEM parking brake cables was to remove the spring. And the TSM brackets look virtually identical to 79-85 caliper brackets (and identical to the brackets you're using).
For $320 I have a pair of calipers that plugs and plays without modification. To me it's money well spent for a required vehicle safety item.
More time was spent painting the calipers (and the drying time) than the install.
1. Go with Chevy 1/2 ton calipers/bracket and Ford 1/2 ton rotors, no parking brake.
2. Find El Dorado calipers or some junk yard equivalent to get a parking brake built in. If I want to use a Ford 1/2 ton rotor I need to swap out a shorter piston in the caliper. Also purchase/fab caliper brackets.
3. Purchase TSM calipers like Unreng above for $320 (reasonable) and get parking brake function without having to comb junkyards.
I'm confused on the TSM option though. Unreng's bracket doesn't look anything like the bracket shown on TSM's website. TSM's website doesn't advertise a special caliper for the conversion. Their rear disc brake kit is for rotors and brackets, no calipers. All I see under calipers is rebuilt GM stuff. Unreng, can you clarify this for us? If you have to replace a rotor do you need to buy it from TSM? Are you able to go to the parts store and get one? You've got to be in this close to $500 vs option 1 above which some claim runs about $100. Thanks in advance for your clarification. Also a huge thanks to the guy going through all this trouble to document his struggle with the GM caliper. Saves us all a lot of hassle whether we go that route or not.
#119
05-22-2011, 01:59 AM
I am not the guy you are asking for, but I think I can answer. TSM uses the 3/4 ton chevy rotors. However, the TSM calipers are modeled after the caddy cals., but with changes, ie. a smaller piston to clear the rotor with the pads, and the design is changed so you can mount both either in front or behind the axle, w/o one caliper bleeder being on the bottom.
If you are doing the swap, I'd def. go with the TSM caliipers, with chevy rotors, and I'd do the Astro Van hydro boost swap as well. It is the best mod I've done to the truck. You can't believe the change in the brakes. It is like a new car now!!
And by the way, the photo you posted shows what I believe to be a TSM bracket. It holds the caliper verticle. Most the brackets you find on the net hold the caliper at 45 degrees. The swap is more expensive than you think. I was more than $1,000 into it with everything, and I rebuilt j/y calipers. But of course that was with the hydro boost too. I really wasn't happy with simply the disc swap. It wasn't good enough. But the hydro blew my mind. Keep in mind, though, I did replace all my brake lines, flex lines, master, p.valve, and p/s unit, lines, hydro unit too.
I would think that the disc swap alone, using chevy stuff, w/o the ebrake, would run about $300. Double that with the TSM calipers.
If you are doing the swap, I'd def. go with the TSM caliipers, with chevy rotors, and I'd do the Astro Van hydro boost swap as well. It is the best mod I've done to the truck. You can't believe the change in the brakes. It is like a new car now!!
And by the way, the photo you posted shows what I believe to be a TSM bracket. It holds the caliper verticle. Most the brackets you find on the net hold the caliper at 45 degrees. The swap is more expensive than you think. I was more than $1,000 into it with everything, and I rebuilt j/y calipers. But of course that was with the hydro boost too. I really wasn't happy with simply the disc swap. It wasn't good enough. But the hydro blew my mind. Keep in mind, though, I did replace all my brake lines, flex lines, master, p.valve, and p/s unit, lines, hydro unit too.
I would think that the disc swap alone, using chevy stuff, w/o the ebrake, would run about $300. Double that with the TSM calipers.
#120
05-22-2011, 12:53 PM
Above is the picture off the TSM website. I see spacers and extra bolts here (not to mention gold paint) that aren't on Unreng's picture. I just found the answer to my question about the modified caliper though. They call it a "Large G.M. Rear Caliper" which is a new not rebuilt caliper, the set costing $320. I'm a little nervous about that parking brake linkage hanging down so low when I drive over rocks and brush all the time but I suppose I could build a guard around it. Maybe Unreng can comment on that too.
I didn't want to get into this but since you brought up the brake booster I already have a different master cylinder, out of a 2004 F-150, and yes the brake power is like a new car. In fact I swapped nearly everything but the suspension from the F-150 into my bronco. Now both of my rear brakes have blown seals and I need to do something. The whole rest of the system is designed for discs all around so it's time to make the swap. I don't want to clutter the discussion with my specific challenges as this is supposed to be about swapping drums for discs on old ford trucks. Anybody that wants to get into my specific issues can google "Quint's Bronco" and you'll find my site.
What we need is a brief and concise documentation of the rear disc conversion options, some pictures, part #s and prices so any idiot like me can easily find it and know what my options are. F-250 Restorer did an awesome job of documenting one of those options but it starts on page 7 of a rather long thread on just one forum. Whatever I do I promise I'll document the crap out of it on my site and post a link here.
Quint
Thread
Thread Starter
Forum
Replies
Last Post
wpnaes
S. California Chapter
12
04-24-2015 10:10 AM
F-250 restorer
1973 - 1979 F-100 & Larger F-Series Trucks
4
11-24-2014 08:31 AM
nstueve
1987 - 1996 F150 & Larger F-Series Trucks
38
09-25-2012 10:30 PM
