(UPDATE)Anybody that still can't get the Chebby discs to stop?

[Blue71]

I have wrestled with my stopping power on my Chebby conversion for 8 months now and they still won't stop well at all. I have done everthing. Made sure the install was correct Ground the Calipers 3 times till I have over 1/2" clearance so I know they aren't hitting. I am using the '76 F250 Camper Special M/C. Feels like I stand on the brakes as hard as I can and it slowly comes to a stop. On the trail...if the Bronco dies on an upward hill...its all I can do to get it stopped from rolling backwards. I have adjusted the rod at the stock booster in every position from to long..to to short and all in-between. It still feels a little like when the pedal is pushed all the way down...that you are bottoming out on something and its not letting the pedal compress the fluid all the way. My '71 has power drums and 33's and i'd take it any day over my Chebby discs as they are now. Heck...my '68 non power 4wheel drums works better too. Anybody else know why this thing won't stop? I'm about to give up on it.

Thanks Much,

Blue71

 

[Hazegray]

I have the same problem in my 71! It's been just over 1 year since my WH Booster install. The front brakes grab fairly well at 1/4 peddle, but after that, it seems like the vacuum booster runs out of "boost". I still have my original brake distribution block so I'm leaning towards getting an aftermarket brake distribution valve.

 

[DBrown]

I am planning to run this setup and I am also planing to use a Full Size Bronco proportioning valve. the 79 FS I pulled it off of was disk/drum with power brakes. I would like to go hyro boost also but I will probably have to wait on that untill I can gather some cash.

 

[4xfloored]

I have the chevy disc.....and it sucked with the stock m/c then I put on the BC bronco's power brakes and MAN WHAT A DIFFERENCE !!!! that booster rocks.... I can lock em up and it stays staight .... I only have 31's but I highly recomend BC's kit. forget the f250 m/c

 

[hucktruck]

I have the Cheby disks (from ebay Horsepower) and was running the F250 Camper Special but I was not happy. It was better than drums but took a lot of leg and still wasn't sure if I was going to stop. Hydro now and no problems at all stopping other than I need a prop. valve as my rear drums are locking up first. I recommend hydro if you can swing it!

 

[Red Bronco]

I have the same set up as 4xfloored chevy's with BC booster and works great!

 

[JWMcCrary]

Ditto here. Same problem until I put on the Wildhorses Hydroboost setup. It will dam near turn wrong side out now when you "touch the brakes". My original setup was from Horsepower sales off ebay. I'm still using everything from that setup but the master cylinder and the brake lines going to the "H" block on the frame.

 

[TOFIC]

Ditto here. Same problem until I put on the Wildhorses Hydroboost setup. It will dam near turn wrong side out now when you "touch the brakes". My original setup was from Horsepower sales off ebay. I'm still using everything from that setup but the master cylinder and the brake lines going to the "H" block on the frame.

I told you so!!! Gloat Gloat Are you a believer now????
Hydro is the way to go!!!
TOFIC
PS as to the poor performance of the chevy system I would look for a pinched closed or partially closed hardline somewhere inn the system.

 

[danny]

I had chevy on my 73 .I bought a new proportioning valve for a factory disc eb. stopped on a dime,no booster.

Now i have chevy on a 68 this time I ran the back drums on an adjustable proportioning valve from jegs.Front chevy discs are a straight run from master cylinder,no valve.

 

[SACHEM]

Do you have the calipers on upside right? The bleeders should be on top. If they are on the bottom not all the air can get out.

 

[DBrown]

Front chevy discs are a straight run from master cylinder,no valve.

so let me get this strait.......you have the line going from the factory master cyc. to the front brakes with no interuption and then use an adjustable for the the rear?

could you possibly use just the rear part of the factory proportioning valve to run the rear drums?

 

[Blue71]

Calipers are correct too. Iwould like to upgrade booster, or go Hydro, but feel like I should have descent brakes now....especially better than my '68 no power, drums. I 've been in situations on the trail where your engine dies, and you have no power assist. I at least want to be able to stop as well as my '68 Drums setup before I rely an a new booster or hydro. Hope that makes cents. Iam planning on Hydro assoon as Ican get this baby to stop a little better manually. Just can't figure it out unless it is the original H-block that I am running. Most said they added a new proportioning valve only if the rear brakes were locking up on them. Heck..Ican't get anything to lock up or even come close. I just slowly cruise to a stop and have a sore , tired leg from the pedal. You can barely hold the Bronco stopped on a hill if the motor dies or is not running. Kinda scary. Again..I just hate to rely on the power or Hydro. Keep'em coming and hopefullywe can figure this out. May try a new prop. valve if Ihave to.

Blue71

 

[fordguy]

what kind of brake lines old rubber lines can swell on the inside and make things hard to stop i had that problem on a 76 w disc brakes (not power)

 

[72Sport]

What is the bore on the MC? I don't have a Chevy conversion but the owners that I have talked to use the 1" bore master cylinder with the Chevy non boosted conversion and are quite pleased. The bigger the bore of MC the more you have to push on the brake pedal to stop.

I just installed a Ford set up with the big calipers and 76 rear drums. I didn't like the pedal force of 1 1/8" diameter cylinder so I changed it to 1 1/16" bore which was more to my liking. I to want to be able to stop without power assist. I have a ten year old Toms bracket and booster which I have added bushings and rebuilt the booster.

 

[Blue71]

what kind of brake lines old rubber lines can swell on the inside and make things hard to stop i had that problem on a 76 w disc brakes (not power)

Fordguy - Just to update everything in the system I replaced all of the brake lines hard and soft in the entire system just before I did the conversion

72Sport- I think I am running the 1 1/8" bore so maybe if I went to another M/C that would help. What M/C are you running that has the 1 1/16"bore? Also ...are you running a prop. valve?

Thanks Much,

Blue71

 

[broncnaz]

I'm with 72Sport on your MC I believe the camper specail MC has a 1 1/4" bore try a 76 up bronco/F150 MC they have a 1 1/8 bore seems like everyone that has tried the camper specail with ch#vy brakes had the same problem you are having very hard brake pedal with little stoppage look at N8's page in the disc brake conversions link he spells it out.

 

[72Sport]

I have a booster so the lines are on the passenger side. You need a MC with the lines on the drivers side. Mine is from a 1986 Ford Van produced after 9/85. It is a one year only MC. I spent a lot of time at a real auto parts store looking at their brake book. 87 and up were also 1 1/16 bore but they had some extra stuff on the ports that I wasn't sure of the purpose so I didn't use it.

I have a stock 76 Bronco P valve from the Ford dealer. I tried the wrecking yard route but they were all rusted on the inside.

You can remove the residual pressure valve in your stock MC by removing the brake line and screwing a #6 sheetmetal screw in the brass insert in the rear brake line port. Remove the brass insert and the valve behind it. Reuse the brass insert. You might do a search on this. I have never done it although the same technique is used to disassemble a Pvalve. I did five of them.

 

[airman]

Just to add, I was going to add the camper special but wanted to try the stock MC on my 75 first. I loved it. But it turns out that the PO had switched the stock 75 MC with something else. I have what looks like a 76-77 MC but the lines are on the driver side. I have no booster.

I have a brand new Camper special that can be had for shipping. I have no reason to use it.

 

[bjack]

Did you try to adjust the brake plunger that goes into the MC?

 

[Socal Tom]

Calipers are correct too. Iwould like to upgrade booster, or go Hydro, but feel like I should have descent brakes now....especially better than my '68 no power, drums. I 've been in situations on the trail where your engine dies, and you have no power assist. I at least want to be able to stop as well as my '68 Drums setup before I rely an a new booster or hydro. Hope that makes cents. Iam planning on Hydro assoon as Ican get this baby to stop a little better manually. Just can't figure it out unless it is the original H-block that I am running. Most said they added a new proportioning valve only if the rear brakes were locking up on them. Heck..Ican't get anything to lock up or even come close. I just slowly cruise to a stop and have a sore , tired leg from the pedal. You can barely hold the Bronco stopped on a hill if the motor dies or is not running. Kinda scary. Again..I just hate to rely on the power or Hydro. Keep'em coming and hopefullywe can figure this out. May try a new prop. valve if Ihave to.

Blue71

Do the rears lock up first? If they lock up hard before the fronts can then it could be part of the problem. Do you have the lines run to the right end? The big resevoir closest to the driver should go to the front. If the rears are locking up too early you can go to a proportioning valve , or a bigger wheel cylinder. Did you completely bleed the M/C before you hooked it up? It could also just be a bad M/C. Not all camper special M/Cs are created equal. For non-power you should try to stay at 1 1/16 or 1 1/8.
Tom
Tom