Hey guys, I am currently in the process of making the conversion from a single to a dual master cylinder. I have already purchased new brake lines, a Cardone A150-1117 master cylinder (used for a 1968 Cadillac) as wheel as new hydraulic hoses and wheel cylinders. I was reading a lot of posts on people doing the same conversion as me but there was a lot of talk about proportioning valves and residual check valves. I'm a mechanic so I know what they both are and how they work. So I guess my questions are, for those who have done this conversion: Should I install a proportioning valve and is it worth it? And if I wanted to put one in anyway, just for the extra step of fine tuning the brake system, which one should I get and where do I find it? Where in the system should I install it? As for the residual check valves....where has anyone gotten them from? Any specific company that makes good ones? And finally where in the system should I install them? I looked at this page (http://www.mbmbrakeboosters.com/index.php?option=com_content&view=category&layout=blog&id=8&Itemid=16) which gives a pretty accurate description of where to put it but I wanted to hear from others who have done this and may have found a better place/way to install them. Any information would be greatly appreciated. Thanks!
And also, does anyone know the outline size of this Cardone 1117 master cylinder? Mine hasn't arrived and I just wanted to make sure its the sam size as the original brake lines (1/4"). Or will I need to buy a converter? Thanks
James,
With drums on all 4 wheels I have been told a proportioning valve is not needed.
With front discs and rear drums,yes.
Let me know how you make out, I am interested in doing the same thing on the two 60's I own.
Brian
On different year models there are different wheel cylander bore and piston sizes,can be a issue. Something to keep in mind. Ken Perry
In the brake systems I have worked on the brake fluid pressure is equal in the whole system, even in the split systems. When the weight front to rear is different you want to have more braking on the heavy end. To achieve that the wheel cylinder sizes are selected to provide the proper braking. Larger diameter pistons provide more braking.
I would think that keeping the original wheel cylinder sizes would be the proper way to go, assuming you are not significantly changing the front to back weight ratio.
I also would not worry about a proportioning valve.
I have never used a proportioning valve on the all from systems, and have used the original brake line size.