Need to plumb up a 53 chevy truck its got mustang two front discs and later model chevy drum rear brakes looking for a basic diagram to get me started has a 87 chevy van master cylinder im not sure if the proportioning valve is in the truck bed with all the other parts or not yet. any body have a diagram that could help with plumbing this thing
So after looking at the couple diagrams i could find do i just run the line from the large side of the master cylinder to the front discs and small side to the rear druns with a proportioning valve run inline? Sound good?
If you are using a dual master cylinder you should use a portioning valve. The type of valve that goes in the line to the rear brakes is not really a portioning valve but a flow control valve. It slows the fluid down so the front brakes come in sooner. They may call them portioning valves but they do not regulate the pressure between the front and the rear like a stock valve does. You will need one from a similar type system, disc front / drum rear.
Go to speedway online, look up proportioning valves, go to the stock looking one and look for installation instructions.
Total BS. The proportioning valve, whether stock fixed value or aftermarket adjustable, limits rear line pressure to a percentage of master cylinder pressure once the knee or crack point has been reached. You are much better off using an adjustable aftermarket prop valve, simply plumbed inline from the rear brake master cylinder port to the rear brakes. Production style fixed value "combination" valves usually include things along with the prop valve you don't need or want, like front metering and a differential pressure switch. These were made and calibrated for certain vehicles, not intended to be universal, like many suppliers want you to believe.
Ok cool I'll order the adjustable one from speedway seems simple to plum in since it's just in line with the rear brakes I'll just run all the front lines untill it comes in.
Some good info here, hope it helps http://www.piratejack.net/index.php?option=com_content&view=category&id=12&Itemid=12
I believe 40 streetrod suggested ECI,these people do this for a living. I would give them a call and get it right.