Just out of curiosity, has anyone changed the original tandem MC for a single MC, like a Wilwood GS Compact Remote Master Cylinder (or similar)? If so, how does it feel and perform? What bore size did you went with and why?
I'm asking this because I'm researching MC options for my 510. I'm currently running a standard tandem MC with booster (that I'm pretty sure has gone bad) and I hate how the pedal feels and the overall brakes (original calipers with the wedge shaped pads. Lockheed design if I'm not mistaken). I'm going to change the calipers and rotors for to a set out of a Citroen Saxo Cup (I'm from Portugal, so I have to be creative with options ) but I fear that the MC will continue to be a problem. I'm also going to remove the booster and give it a try, but a little research ahead of time never hurts...
There's a good reason they went to dual master cylinders. On a single if there was a leak ANYWHERE all the brakes failed. When I was kid it was all to common to hear an accident was caused by 'brake failure'. How often do you hear that today??? Dual systems separate the front and rear brakes so a total failure is basically impossible. Single master is a very bad idea.
Fix your brake booster as it adds 50% more braking power for every pound of foot pressure. Or looking at it another way, it lessens the braking effort and reduces fatigue when driving in traffic or any 'spirited' driving. Without the booster a pedal pressure of 130 pounds produces a brake line pressure of 1,000 PSI, with the booster it's over 1,560 PSI. Do the math. Removing it is NEVER a good idea as it makes stopping harder to do.
To test the booster step on the pedal several times to exhaust any residual vacuum stored. Step on the pedal and hold. Start the engine. What you should observe is the brake pedal will drop slightly. If it does that the booster is working.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
If the brakes are modified in any way, chances are you'll never get the correct bias F/R with a single MC. And Mike posted a very valid point above on safety.
If removing the booster from the system, the way to modernize the brake MC with be to use twin, single masters on a balance bar. Today you can purchase pedal boxes from any brake manufacturer out there that can put the MC top mount forward, reward or even under your legs rearward under a false floor.
This mod will take fabrication, but having done this with the Bronze car, it's a great way to modernize the set up and make part availability easy.
Byron
Love people and use things,
because the opposite never works.
) but I fear that the MC will continue to be a problem. I'm also going to remove the booster and give it a try, but a little research ahead of time never hurts...