Yukon Jack
1/2 ton status
The guy that is selling the booster pictured above has a very good reputation - sure looks like a bargain!
CK5
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The 67-72 One Ton Brake Booster Swap Guide ***PICS***
- Thread starter AJs72K5
- Start date
GRINCH
1/2 ton status
I'm considering it.. I will let everyone know if I decide to purchase one. There was some question on the MC.
I sent this ? to him.
This is going on a 72 K5 Blazer. I am running dual disk brakes with large calipers. Dana 60 front with disks and front calipers from a 3/4 ton on my rear 1 ton axle.I bought an adjustable prop valve/dist block already. It has 3/8 - 24 ports on it.
I do not have a large MC with those ports. I can sell you the booster & bracket package for $200 shipped, but you will have to get your own MC & lines to match that adj prop valve.
Is it the ports that are the problem or the MC size for the brakes I'm using? What size are the lines and fittings going into your dist block.
Probably both. MC has big 1 1/4 piston and 1/2 & 3/8 ports.
So I'm a little confused at this point.
I'm not worried about the fitting sizes since I can get a new prop valve or use his stock block. But this was posted earlier.
Do you have access to 4 wheel disk brake prop valves if a user wanted them?
I have been concentrating on getting the major components fitted on these and haven't looked into 4wheel DB because of the limited demand. The prop valve would have to have the exact same line fitting sizes, as these lines are not standard anywhere. I have them specifically made for this system.
I sent this ? to him.
This is going on a 72 K5 Blazer. I am running dual disk brakes with large calipers. Dana 60 front with disks and front calipers from a 3/4 ton on my rear 1 ton axle.I bought an adjustable prop valve/dist block already. It has 3/8 - 24 ports on it.
I do not have a large MC with those ports. I can sell you the booster & bracket package for $200 shipped, but you will have to get your own MC & lines to match that adj prop valve.
Is it the ports that are the problem or the MC size for the brakes I'm using? What size are the lines and fittings going into your dist block.
Probably both. MC has big 1 1/4 piston and 1/2 & 3/8 ports.
So I'm a little confused at this point.
I'm not worried about the fitting sizes since I can get a new prop valve or use his stock block. But this was posted earlier.
Do you have access to 4 wheel disk brake prop valves if a user wanted them?
I have been concentrating on getting the major components fitted on these and haven't looked into 4wheel DB because of the limited demand. The prop valve would have to have the exact same line fitting sizes, as these lines are not standard anywhere. I have them specifically made for this system.
bp71k5
3/4 ton status
The combination valve that guyis using looks identical to the one I got from inlinetube. Id bet the fitting sizes are the same. This guy appears to have some kind of valve on the front output (maybe a holdoff valve) but I bet that could be removed. You could probably use a 4wd valve instead or you'd have to add your proportionong valve downstream of the rear output.
One additional bit of info on all of these brass valves is that the plug they use on the top for the second front line was hollow on mine and could let an air pocket sit under it. Did anyone else remove theirs to check that?
One additional bit of info on all of these brass valves is that the plug they use on the top for the second front line was hollow on mine and could let an air pocket sit under it. Did anyone else remove theirs to check that?
70BlazerX2
1/2 ton status
I have hydraboost on my 69 Rollback...it was fun..i had to use a 73-87 adjustable rod and sleeve it to the 69-72 rod to the pedal...rest was a bolt on...I had to put the hydraboost on due to the P-series chassis has factory 4wheel disk brakes and 19.5 tires. This truck will stop on a dime every time..loaded or not...
I will get pics soon...and post here...great thread
I will get pics soon...and post here...great thread
Peteasauras
Registered Member
What size lines should I run. Looks like the stock lines were 1/4, but the lines with the small fitting available at NAPA were only 3/16. Is this two small? Should I get 1/4 lines? My prop block also has two outputs for the front lines, should I just plug a hole and run the stock lines or is there a reason to run the fronts separate?
Peteasauras
Registered Member
Answered my own questions. 3/16 line are fine.
http://coloradok5.com/forums/showthread.php?t=255590&highlight=brake+line+size
But still confused about what port is for the rear brakes off the mastercylinder? If the front (towards grill) port is for rear than the link above looks hooked up wrong.
http://coloradok5.com/forums/showthread.php?t=255590&highlight=brake+line+size
But still confused about what port is for the rear brakes off the mastercylinder? If the front (towards grill) port is for rear than the link above looks hooked up wrong.
bp71k5
3/4 ton status
Back in 69-72, the brake lines hook up as shown in your link. The newer master cylinders have the ports switched so if you use one, you're supposed to swap the lines over too.
That's true on the 1/2 ton master. But on the 3/4 ton and 1 ton masters the front brake resevoir is in the back on the master cylinder.
bp71k5
3/4 ton status
That what I was trying to say. The picture is right for a 1/2 ton master, but not for the others.
ChefBear
1/2 ton status
???
Brian, AJ.
Are you guys telling me I got mine backasswards?
Hmmm?
Brian, AJ.
Are you guys telling me I got mine backasswards?
Hmmm?
If you're running a 1 ton master cylinder, then I guess we are. But with that said, if you're stopping good, and everything locks up at the right time, I wouldn't change it.
bp71k5
3/4 ton status
Only if you drive forward a lot.
Seriously though, I'm not sure how much it matters. Someone else will have to comment what the deal is. I didn't hear about tons of brake failures in the 1970's so it can't be that bad.
ChefBear
1/2 ton status
naw...
I'm gonna go check tomorow, but I swear I thought they were right when I did them. It stops like a champ! If it is backasswards then everybody better start switching cause I may have stumbled on to something.
I'm gonna go check tomorow, but I swear I thought they were right when I did them. It stops like a champ! If it is backasswards then everybody better start switching cause I may have stumbled on to something.
Peteasauras
Registered Member
Well hopefully it works either way.
(crossover tube is just so it doesn't leak during setup)
(crossover tube is just so it doesn't leak during setup)
bp71k5
3/4 ton status
Actually, you have the adjustable valve output pointing forward so as long your rear lines plug into the front of the valve (the side with the adjusting knob) you have it hooked up right. You'll need to modify your drop lines down to the frame though.
Pretty good info, Thought i would give it a bump, and maybe request to make it a sticky??? what do you guys think?
bump for reference, right in the middle of this swap.
garlicbreath
1/2 ton status
I just ordered mine for my 71K5 with D60 and 14B from autozone today for 141.00 shipped to my door. That's with the 35$ core charge that I will get back so 99.00 after the 10$ gift card for the booster and master to my door in 3 days. Woot woot!
I used the 50-1007 part number mentioned by the original poster.
They are doing a 20% deal until june 16th with free shipping and you also get a 10$ gift card,
Code is 20stack10
I have 37's one tons and the half ton booster now and it's scary trying to stop, especially at 13k feet altitude when the motor dies.
I used the 50-1007 part number mentioned by the original poster.
They are doing a 20% deal until june 16th with free shipping and you also get a 10$ gift card,
Code is 20stack10
I have 37's one tons and the half ton booster now and it's scary trying to stop, especially at 13k feet altitude when the motor dies.
