Setting adjustable proportioning valve???

[brianrupnow]

I have completed the front disc brake installation in my roadster pickup, and I am curious about setting the adjustable proportioning valve in the rear brake line. As I remember from a similar installation about 13 years ago, you set it so that when the brakes are applied, the rear drum brakes engage slightly before the front discs, so as to keep the car in a straight line when stopping. First question---Have I got that right? and, Second question---How the heck can you tell something like that???---Brian

[brianrupnow]

Damn---I had it backwards.--Just read in the Hortons catalogue that "Fronts should lock up just before the rears to keep the rear end from skidding around."---still, as in my previous post, this is a hard thing to determine.

[atichargr]

Damn---I had it backwards.--Just read in the Hortons catalogue that "Fronts should lock up just before the rears to keep the rear end from skidding around."---still, as in my previous post, this is a hard thing to determine.

I have not had to do this before ... but I do remeber reading somewhere that you can do this on a slick surface such as gravel... you want the front to lock up just before the rears.... I hope this helps you .. the only other way I would think to do it is where some pressure guages..

simon

[firebird77clone]

I had heard to use a large parking lot. Make progressively aggressive stops, and small adjustments of the prop. valve until you get it 'feeling' right.

[DA34GUY]

Brian----
Close the valve, open all the way and count the turns out, turn in 50% and yer good to go.
Has worked for me on the last 25 or 30 I've done.
Good luck

[kitz]

sorry I didn't see this. Good procedure;

http://www.chevyhiperformance.com/te...lve/index.html

Kitz

[Dave Severson]

If you have a brake pressure gauge, check the pressure at the master cylinder, then at the front and the rear. Brake pressure should work well at about 60/40 front to rear.... Counting the turns on the knob is probably just as good, and a whole lot cheaper then buying a brake pressure gauge if you don't already have one....

[shoprat]

I have a lot better luck using a factory type pro valve. It also separates the front
from rear if you have a leak on one end. I went thru this pretty thoroughly. I'm
assuming you used dual m/c.

[bentwings]

Count the turns. Start in the middleof the range.

We did it on a sandy parking lot with my Willys. Once we got it set about right I tried it from about 40 mph. Emergency stop. Those big Hoosiers on the rear are incredible. The car stops very hard and straight. Brakes don't even get hot. About 250 with my heat gage.