Originally Posted by S10 Racer
I am getting ready soon to start running brake lines on my S10. I have converted it to manual brakes to do away with the power booster. I have disc brakes on front and drum brakes on the rear. I have a few questions I need answered so I only have to do this once. If anyone can help, please do.
1. The manual master cylinder has a larger reservoir in the rear than it does in the front. Is the larger reservoir for the rear (drum) brakes?
2. What size of lines do I need to run? Is the front lines smaller than the rear?
3. I have a Wilwood Proportioning valve I was told I need to install between the the master cylinder and the rear brakes because I have disc brakes on the front. Is this true?
4. I also have a 10psi residual valve. Is this for the front (disc) brakes? Can I install it straight off of the master cylinder?
I know this is alot of questions but I need to do it right the first time. Any help would be welcomed.
1. Normally, front discs are fed from the rear reservoir and drums from the front reservoir.
2. Line size won't make a lot of difference on a street driver. Larger lines will help brake response on a car where the driver is on-off-on-off the brakes in a rally/road course type of car.
3. Your system will require a metering valve to the front disc brakes and a proportioning valve to the rear brakes. Both these valves are used together in a combination valve. The metering valve reduces spike pressure to the front discs to prevent dive. The proportioning valve limits pressure to the drum brakes to prevent lock-up.
4. Your system will also require a 10# residual valve in the rear brake line. This valve will retain pressure in the line to the rear so that you will have a better pedal.
I have to wonder if you know there is a difference in master cylinder bore size between power and manual brakes. If you're planning on using the same cylinder you used for power brakes, you're in for a surprise.