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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,289
Your '87 came with two changeover valve switches mounted on the top left of the factory blow off/recirculation/diverter valve. You can use one of those with the summit racing rpm switch. Or buy a new one from pelican parts.

You hook up the WUR boost signal vacuum hose to one of the two hose nipples on the valve that are closed regularly but open and let air through when 12 volts is applied to the changeover valve. The other nipple that is only open to the other one when 12 volts clicks the internal solenoid goes to the bottom hose fitting on the WUR where the original hose went.

Wire ignition switched 12 volts to the changeover valve and the other terminal on it to the rpm switch. Follow the directions that come with the rpm switch for the wire colors and what they do and how to program the rpm into it. It's easy.

Then the RPM switch will open and ground the wire from the changeover valve at the rpm you programed into it and the valve will open so boost pressure will go to the WUR/CPR and lower control pressure making a richer AFR at the rpm you programed into the rpm switch.
Old 07-22-2014, 02:13 PM
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