This is the ZZ with everything stripped off to accept the Edelbrock Pro-Flo EFI. I decided to dress up the engine with some of Edelbrock's Elite Series aluminum valve covers while everything was apart.
The ZZ4 with the Edelbrock Pro-Flo EFI and Elite valve covers installed. This photo was taken after the EFI had been installed for a while as the engine is surrounded by the new tubular body. Note the different firewall with easily accessible electronics and black-topped Tupperware box for the ECM.
The manifold assembly from the left, or driver side: The manifold comes pre-assembled with the two-barrel air valve, fuel rails and injectors and all the sensors already in place. All you have to do is install new intake gaskets and drop the manifold in place--just like installing a regular carburetor manifold. Seen here is the left bank's fuel rail and fuel injectors, the wiring loom for the injectors and the throttle control. I was able to use my existing throttle cable and its bracket that used to attach to the back of the Q-jet. All the injector wiring is fitted to size. You merely plug each wire into its corresponding injector. The round cylinder thingy on the rear of the air valve is the idle air control solenoid (IAC). This is an OE Ford part. It can be adjusted and turned off or on via the calibration module. I had a surging problem at idle when crawling large rocks. Turning the IAC off cures the problem.
The other (right) side of the manifold assembly: Here you see the right fuel rail, semi-hidden by the rectangular manifold absolute pressure sensor (MAPS). Sticking out of the side of the air valve is the throttle position sensor (TPS) and to the left you can see the other side of the IAC and its plug. Each plug is a different shape so there is no way to fit the wrong plug on the harness into the wrong sensor. To the front of the engine, on each side of the thermostat housing, are hoses attached to each fuel rail. The blue hose is the high-pressure "IN" line coming from the framerail-mounted fuel pump. Fuel passes through the left rail, feeding the left-bank injectors, into a braided-steel line that runs under the distributor and around the back of the engine and into the right rail. After feeding the right-bank injectors, the leftover fuel enters the black low-pressure return line and goes back to the tank.
I purchased this 20-gallon aluminum fuel cell from Summit Racing. It is intended for drag racing and features two AN fittings on its top side, along with a centered filling cap. Underneath is a small sump that extends below the bottom of the tank. Two more AN fittings are provided there. You can just see the sump and these fittings at the frame line by the taillight. The main fuel feed runs out of the right lower fitting (red) to the fuel pump. The left lower fitting (blue) was capped off as a drain. Up top, one fitting is the fuel return line while the other goes to a tank vent mounted high in the cage with a manual rollover valve installed inline.
Beneath the fuel cell is the Edelbrock-supplied high-pressure fuel pump (round and black) connected via the high-pressure blue fuel line to the supplied fuel filter (round and silver). You can just make out the sump in the bottom of the 'cell to the right of the pump. This sump is necessary to provide fuel to the pump at any vehicle angle. You don't want the pump to run dry and allow air into the system during off-camber maneuvers. Edelbrock advises mounting the pump and filter as close to the tank as possible.
Although it looks complicated, the harness is very straightforward and with its OE-type plugs, is impossible to screw up. In the left upper corner is the ECM. Below it are wires to fuses and the fuel-pump relay. The calibration module phone-plug link is in there as well. Moving to the center and down are all the wires to the fuel pump and O2 sensor. Also in this cluster are four wires that run to outside sources--two to 12V power and two to ground. Further to the right of the downward-facing wires are all the wires and connections that go atop the engine with plugs for all the manifold sensors and the fuel injectors.
While your stock distributor is out of the engine for the manifold change, you must completely disassemble it and relieve it of its duties of firing the ignition and advancing the timing. These jobs will now be handled by the ECM. All the parts shown are discarded except the main body, the driveshaft and the drive gear. My engine used an HEI distributor, but Edelbrock supplies conversion parts for older, points-type distributors as well.
In place of the ignition components in the distributor body goes this Hall Effect sensor. To the distributor driveshaft mounts a shutter wheel (not shown) that, when spun by the camshaft, triggers the HE sensor, telling the ECM the engine rpm and position of the Number One cylinder. This info allows the ECM to fire the fuel injectors in the proper order.
The only sensor that isn't pre-installed in the intake-manifold assembly is the 02 sensor. A 1/2-inch hole must be drilled in the right-hand exhaust pipe as near to the exhaust manifold or header flange as possible. Then a supplied bung is welded in place over the hole. Finally, the supplied 02 sensor can be threaded into the exhaust pipe and the plug connection made into the Edelbrock harness.
Inside the ECM is a place for a chip to plug in. The ECM comes with the system with no chip installed. A postage-paid card is included in the system's paperwork. You must fill out this card with your cam specs and send it to Edelbrock to get a chip that will work with your engine. The process only takes a couple of days. Once you have the chip, it only takes a couple of minutes to install it.
The ECM must be mounted in a clean, dry place away from excessive vibration. Ours now resides in this Tupperware container conveniently mounted under the hood where I can get to it easily. The Tupperware keeps everything clean and dry. Foam padding helps the vibration issues.
The calibration module is a tool for both monitoring and adjusting the Pro-Flo. No laptop or other outside device is required. The module plugs into the Edelbrock harness via this phone jack, which is mounted under the dash in an easy-to-reach spot. The module can be operated by a passenger (never by the driver) while the rig is being driven.