The actuator bolts in place in the RHD car using the original LHD brackets and the vacuum hose attaches to a capped off pipe near the throttle butterfly - easy! Then I cut off the original cable which went to the accelerator pedal in the left had drive version, and retained the threaded end that mounts on the actuator.
I then purchased a generic bicycle brake cable of 2m length and cut the outer casing to 125cm to run in a smooth arc round the back of the engine bay to the mounting point for the accelerator cable. I fashioned a suitable mounting point for the cable at the manifold end using a flat piece of steel and a threaded bicycle bake adjuster. Using conventional and hot melt heat shrink the ends were secured to the cable outer.
I had previously cut off the cable nipples and then silver soldered a trunnion nipple 6x9mm in dimension to one end of the cable and fitted that end to the actuator. Then I wrapped the unsoldered cable end around the throttle cable 'wheel' to the point where the auto kick down cable was fitted, marked and cut it to length, then silver soldered another 6x9mm trunnion nipple to the cut end. In order to fit the cable into place at the throttle end, I made 2 slots in the side of the throttle 'wheel' to enable the cable to wrap round the ‘wheel’. (see photos) Once all the linkages were in place, then the actuator cable was adjusted to match the amount of slack that the accelerator cable had.
See attached picture for actuator check procedure.
The 90 model was not fitted with a factory speed sensor in the instrument panel, so a reed switch from Jaycar Electronics was mounted into place using epoxy resin glue, and leads soldered on to the reed switch for the connection to the flexible circuit board on the back of the instrument panel.
The wires were then soldered to the terminal pads marked RSW and (-). There was a yellow wire to 2G on the connector which was unused (180kmh switch) so I cut the wire and relocated that pin to 2F for the speed sensor output to the cruise control module. Before reassembling the instruments, I checked with an ohm meter that there are 4 closures of the switch per input shaft revolution.
The other inputs to the cruise ECU are stoplight/brake switch and clutch switch (circled in violet). The clutch switch wire to tap in to is the brown with white trace. The stoplight switch has to be replaced with a dual contact switch - one contact for stop, other for brake (one contact closed while the other is open) A suitable switch is Tridon TBS016. As far as 12v power goes, you need to pick up battery (white with green trace) from the 'hot' side of the stoplight switch, and ignition for the cruise on/off (black with yellow trace) from a 2 pin connector (circled in blue) just left of the clutch switch.
Switch operations as follows…..
Foot on brake=brake switch open
Foot on brake=stop light switch closed, 12V to stoplight switch input on cruise ECU.
Foot on clutch=clutch switch closed, ground on clutch switch input on cruise ECU.
Gear lever in neutral=ground on clutch switch input on cruise ECU.
Illumination on the cruise master switch was wired to terminals G&H. There was a unused accessory plug which was behind the
blank plate where I placed the cruise main switch - I cut off the small red & red/black wires and connected them to G&H on the cruise main switch plug(circled in green).
Since I could not find a steering column stalk with the resume/accel-set/coast switch in it, I used a small toggle switch with a spring return (on-off-on) to centre and mounted it in a spare switch location next to the dash light dimmer.
I have attached the US Miata schematic diagram as an aid to wiring it all up.
As long as you have soldering skills and can use a multimeter, putting the wiring all together should not be too difficult. I heat shrunk all the solder joints.
DISCLAIMER: As this installation involves working on the accelerator cable, take care and test that both cables work independently and do not foul one another. The information provided is for guidance only, and any work undertaken is at your own risk.
Regards,
mx5jag
