Questions about brake lines

[metallicareload99]

First off, is the hold off valve an absolute must have?  And I've been under the impression that the brake lines need to be double flared at the fittings.  Does this require a special tube flaring kit?

I plan on installing a disc brake kit and want to use as much of my existing brake lines as possible.  This will require at least cutting of the rear brake line and installation of a proportioning valve, and probably a hold off valve for the front discs.

Does any one have a recommendation for the proper flaring tools and a good way to cut the tubing on the car?  Where can I get the nuts that will go on the new flared ends?  I don't have any of the tools needed for this work yet.  Any input is appreciated

[Charger_Fan]

I'm not sure what you mean by "hold off valve", but I can help with the other stuff.

Use a tubing cutter to cut your brake lines. This will leave a clean end that won't want to split when you flare the tube.
Here, I found a good how-to article from Car Craft...
http://www.carcraft.com/howto/116_0701_stainless_steel_tubing/index.html

[Ghoste]

The hold off valve or some kind of valve that will balance pressure between front and rear is a must, yes.  Without something in there to control the application pressure, the first time you use those brakes in a panic situation, the car is going to swap ends.

[Charger_Fan]

The hold off valve or some kind of valve that will balance pressure between front and rear is a must, yes.  Without something in there to control the application pressure, the first time you use those brakes in a panic situation, the car is going to swap ends.

Isn't that what the proportioning valve does?

[Ghoste]

Yes, I tend to very wrongly use brake terms interchangeably.  I'm not the only guilty one but thats no excuse and it perpetuates the misnomer.  The proportioning valve does just what it's name implies and sends the proper balance or portions of fluid to front and rear to ensure pressures are correct.  The hold off is also called a metering valve and is used to slightly delay the application of the front discs.  Another way of looking at it would be like a helper valve for the proportioning valve.  That isn't a completely accurate way of looking at it but it's purpose is along the same lines, to prevent the car swapping ends under heavy braking.
Musicman knows brake systems inside out and upside down and can explain them better than anyone when it comes to making it understandable.
The bottom line is this, with the disc brakes you should have some sort of hold off or metering or whatever valve to perform the function. (sometimes you can get an "all in one" valve usually called a combination valve)

[Charger_Fan]

Well, I certainly can't say that I know all the in's & out's about brake systems myself...more often, it's just enough to get myself into trouble. So your post made me do some research.

Apparently, the disc brake proportioning valves I've always taken notice of were the combination type, like this type that I have on my Charger. The hold off valve pull handle being on the end.


The other styles of prop valves I've always associated with a drum/drum application & haven't given them much thought. With all the resto's I've seen done on this site & others, I've never really stopped & looked at these valves. Woops.



So thanks for setting me straight, Ghoste.
BTW, in my searching, I also found Inline Tube's site showing new valves available & thought I'd post the link here for others to use.
Mopars are near the bottom; http://www.inlinetube.com/Prop%20Valves/pro_valves.htm

[Ghoste]

Good link.  I think some of those have been unavailable for some time so it's nice to know.

[metallicareload99]

Thanks a lot guys, that article will be helpful.  I got a "Ridgid" brand double flaring kit.  Cost around $100, so hopefully it'll work and last a long time.

I have a new question, front disc/rear drum vehicles have been coming off the line for decades now, would those have a hold off valve/metering valve that I can use?  I think this is the last part I need for my disc brake upgrade and I'm trying to avoid making one special order for one little part, shipping to Alaska is expensive.  Thanks again