To Brake Gurus,
Installing the OE ABS system, my first thought was run a line from the master cylinder primary to the proportioning valve and then a line from the proportioning valve to the MC1 inlet of the ABS module. But, the ABS module sends fluid to diagonal wheels so the proportioning valve would be restricting flow to diagonal wheels - not good!
The Factory Service Manual includes this: (ABSCM = ABS Control Module)
E: EBD (ELECTRONIC BRAKE FORCE DISTRIBUTION)
The EBD system utilizes the function of the conventional ABS. This system prevents premature locking of the rear wheels by using electronic control instead of a proportioning valve. The system provides a feature to optimize the brake force distribution to the front and rear wheels according to change in loading conditions or displacement of the center of gravity during deceleration.
The ABSCM calculates the optimum brake force distribution from the difference in speed between the front and rear wheels. Based on the results, the ABSCM controls the rear wheel brake pressure through the ABS hydraulic unit (H/U) to achieve the optimum brake force distribution suitable for the driving condition.
The proportioning valve is disused on EBD equipped vehicles.
Now my question: Assuming I install the OE ECU, am I correct in not using the proportioning valve? Should I plumb the master cylinder primary line to the ABSCM MC1 port and the master secondary line to the ABSCM MC2 port?