under floor brake master cyl. question

[meteorman]

I am debating between an underfloor brake pedal/mc setup. $75 on speedwaymotors.
or a more expensive system that allows for underdash Kugel system, $240ish.

I am trying to keep costs low, so I am going to use my master cyl from the motorhome that I tore down and I'm using both axles/brake setups from the motorhome, but it was hooked up to a hydraulic boost system.

Am I ok to use the master cyl from the motorhome without the hydraulic system?

I am thinking I should be fine, because my rat rod is going to be much much lighter than the motorhome was and it has disc brakes up front with drum on the rear duals. The brakes are huge, and I'm hoping that the master without any boost will work fine. Can I just hook it up the the bracket under the floorboards?

What do I need for proportioning valves? check valves (or whatever they're called) , since it will be lower than the brakes? how do I know what specs I need for them?
thanks for your input!

 

[hotrod preacher]

i can tell you for certain you will need residual valves...

10 lb rating for drum brakes; 2 lb rating for disc

as to the hydro-boost, i am fairly certain you will not need it, but the master cylinder may or may not attach to your speedway underfloor bracket...

personally i would get a master cylinder from speedway that was compatible with the under floor bracket...

i also rcomend an adjustable prportioning valve on the rear brake line to "fine tune" the brake bias between front n rear disc/drum set-ups


hope that helps answer your question!

 

[dogpatch1]

master and proportioning valves

the two items you will need, are called risidual valves, and yes they are designed to be used when your caliper or wheel cyl.'s sit higher than the master. they are basically a one way valve, they allow fluid to flow to the calipers and wheel. cyl.'s but only allow a slight bit to return to relieve pressure.

they make them in 10 psi, and 2 psi, one is for disc and the other for wheel cyl.'s.

they run about 10.00 each AND should be plummed in line as close to the master as poss.
as far as your master it will most likely be fine, however speedway also has a combo master and underfloor pedal, avail for 99.00 its a super deal, i have used them on several builds. and for 100.00 its worth having the new one verses a used one.

if you need part numbers hit me up.

george

 

[rainman]

What they said!![cl[cl

 

[mopar4life]

watch for tranny crossmember clearance. that is what i'm dealing with. i think firewall mounts just look bad. under dash units are fun to check and fill. not like we have to worry about fluid on the carpeting. maybe peeling the paint on the street sign floor board.

 

[meteorman]

however speedway also has a combo master and underfloor pedal, avail for 99.00 its a super deal, i have used them on several builds. and for 100.00 its worth having the new one verses a used one.

if you need part numbers hit me up.

george

I only see one for 119. Is that the one you are talking about. Seems like the same pedal, but with a master. I think that's worth it too.
thanks for the help with the residual valve info. this seems pretty straight forward.

I'm still not quite sure how to set up and adjust a proportioning valve.
I guess I'll get it set up and do some research and figure it out. Or take it in and have someone who knows what they're doing adjust it for me.

 

[dogpatch1]

part numbers

yep looks like they raised the price this month, part number on the master cyl/pedal combo is, 119.95

916-31926

risidual valve front disc is, 14.99
910-31345
risidual valve for read drum is, 14.99
910-31347

i also plum in a adjustable proportioning valve in the rear line after the residual valve,
the one i stock and use 32.99 and is part number,
910-31353

these are all anodized but i spay em with brake cleaner and they are aluminum under, or i paint 'em black.

all of this together and you will still come in under 200.00 bucks.
hope it helps
george

 

[old lady's mad]

dont forget rpm ron pope he makes them.

 

[meteorman]

location of residual and proportioning valves?

I'm wondering if it matters where I locate the residual valve and proportioning valves. Do they need to be near the master cyl? or can I run the lines back and locate them near the rear axle on the rear brakes?

I bought the Speedway parts recommended by George,(thanks) and have the pedal mounted, ready to run the brake lines. I'm ready to do the back ones, but I'm not sure what people do with the front brakes with quarter elliptic spring suspension. I'm thinking I'll run the lines up onto the radiator support and have long rubber lines running from the wheel to the radiator.
anybody have pics handy?

 

[LUCKY DEVIL 13]

Here ya go I used this as a reference for mine

 

[rainman]

As you can see in the dawing there's not a definate spot the residual valves need to go!! So I recommend putting them where a break in the lines is convenient!! In some ways they actually make running the lines easier!!

 

[meteorman]

newb question

I have a question that comes from simple minded ignorance[S about brakes. I am plumbing the lines and installing the residual valves between pre-flared sections that I am getting from the local auto parts center.
my question is, do I need the long brass fittings on the end that connects to the residual valve? they seem really deep (in the female threads) I already bent a line that has the short male threaded fitting, and it doesn't go deep enough into the residual valve to hold the line still, it pulls out and moves.
I hope i am making sense. It seems to me that the line should have no play in it to push the flare up against the fitting. am I right on this.
Ugh. I am getting tired of bending and wrecking brake lines. Fortunately they are fairly cheap.

 

[sneakysnake]

I have a question that comes from simple minded ignorance[S about brakes. I am plumbing the lines and installing the residual valves between pre-flared sections that I am getting from the local auto parts center.
my question is, do I need the long brass fittings on the end that connects to the residual valve? they seem really deep (in the female threads) I already bent a line that has the short male threaded fitting, and it doesn't go deep enough into the residual valve to hold the line still, it pulls out and moves.
I hope i am making sense. It seems to me that the line should have no play in it to push the flare up against the fitting. am I right on this.
Ugh. I am getting tired of bending and wrecking brake lines. Fortunately they are fairly cheap.

unless it has a seat in it then its NPT and will require a fitting to match the line size

 

[meteorman]

New question. retaining clip on push rod

Thanks SneakySnake, I'm ordering the adapters from speedway now. I noticed that my proportioning valve had those with it, but the residual valves didn't. so I'm getting them.


Now, I need help with the retaining clip.

the directions on the speedway pedal master cylinder (step #6) say to reinstall the retaining clip on the push rod. How do I do this? if I install the retaining clip before the push rod is installed, then I can't put the push rod in. If I push the rod in, then I can't figure out how to put the retaining clip on.
?? please, I'm sure this is simple, but I am missing something here.

 

[sneakysnake]

Any pics of the rod so we can see exactly what you got?

 

[LUCKY DEVIL 13]

Thanks SneakySnake, I'm ordering the adapters from speedway now. I noticed that my proportioning valve had those with it, but the residual valves didn't. so I'm getting them.


Now, I need help with the retaining clip.

the directions on the speedway pedal master cylinder (step #6) say to reinstall the retaining clip on the push rod. How do I do this? if I install the retaining clip before the push rod is installed, then I can't put the push rod in. If I push the rod in, then I can't figure out how to put the retaining clip on.
?? please, I'm sure this is simple, but I am missing something here.

I had the same issue with the clip on mine but if you just move it around a bit as you are pushing it in it will snap into place