I’m going to use the original Powered Steering box .. but pretty much ditch the rest as my car does not have a vehicle speed sensor.
However. in the MK3 Toyota MR2 there is an electronic powered steering pump that does not need a speed signal to ramp down. This motor uses a clever ECU with sensors to measure the “turning effort” required, and adjusts the motor output accordingly.
Essentially when you’re at high speeds or in a straight line, the motor will detect low or no effort required and ramp down.. likewise if you start turning or slow down and more effort is required, it’ll ramp back up accordingly.
Luckily iv upgraded the alternator to handle the extra load of the electronic pump.. all il need to do is make up the flow and return hoses to the box and run the wiring.
Where i need some advice is on the ignition live … I could easily connect up to IGN.. but the pump would immediately start drawing 50amps.. where can I find a 12v supply that is only live once the engine has been started ?
Here is a wiring diagram showing how simple the setup is! There is a VSS input on the MR2 that switches the pump off completely .. but the pump will work and ramp down to low without this input
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) we used to fit a magnetic pick up onto the drive shaft, for speed sensing when fitting cruise control on the 626-rx7 etc. Just a thought maybe. 
Steve.
