...SYSTEMS PLUMBING...
Cooling System...

Radiator Bracket Installation...
...right / left radiator brackets
...10mm wrench
...12mm wrench
...3/8x3/4x36" Hi density automotive grade foam tape
...Install the brackets using the original RX-7 radiator bolts. NOTE:...Our radiator brackets attach to the same points as the original RX-7 radiator, but move the bottom of our radiator forward to a vertical position. The right and left brackets are almost mirror images of each other, except that the driver's side bracket has a wider wing seal on it's lower outward side.
...Part of the plastic underbelly tray below the radiator should be removed between the steering rack and the bottom of the radiator. This modification more area for the hot air exiting the radiator to escape the engine compartment.

Radiator Installation...
...Radiator
...radiator aluminum upper seal panel
...10mm wrench
...Drill & 5/16" drill bit
...2x2x36" low density foam seal material
...The foam material seals the area between the bottom of the radiator and the plastic underbelly tray. Sealing this area prevents cool air from bypassing under the radiator. Cut the foam seal material as needed to fit.
...Slip the radiator into the installed radiator brackets (slight lubrication of the foam strips may be required. The hi-density foam should prevent any metal to metal contact).
...Place the upper aluminum radiator seal in position at the top/front of the radiator (located by the existing hole at the passenger side/front of the panel). Using the seal plate as a template, mark and drill the other mounting hole along the front edge of the seal panel.
...secure the seal panel using existing & drilled holes.

Radiator Hose Installation...
...upper hose
...lower hose
...(4) hose clamps
...We do not currently supply radiator hoses for the Ford conversion. The best method we have found to help find a compatible hose is to make simple bend and length patterns from stiff wire to help you visualize your requirements as you look thru your local parts house's hose inventory. Often times a hose can be cut, rotated, and joined into a different shape using a short piece of exhaust tubing and a few clamps. Be sure to double clamp the hose to insure that the connecton does not come apart with system pressure, as your exhaust tubing will likely not have the retention "bead" that typical radiator hose connections have that prevent the hose from slipping off.
...Trim the hoses to length & install. Make sure that the lower hose has a spring type insert inside to prevent hose collapse at high RPMs.

NOTE:...If you want to use your stock RX-7 radiator, it will need to be re-located farther forward to a more vertical position. Some people have had success with the stock radiator by removing a pie shaped section from the sheetmetal the radiator bolts to, with the result of swinging the bottom of the radiator forward. Others have used radiators from different applications, using fabricated brackets. Even stock LT-1 Camaro radiators have been installed by denting in the sheetmetal “frame-rail” sections of the RX-7 to make some additional room. Whatever solution you decide on, if you live in one of the warmer climates such as Arizona or Florida, you will need to pay extra attention to directing every last bit of air drawn in by the fan THROUGH the radiator, instead of around it. This means sealing off all the paths above, below, and around the rad with sheetmetal, cardboard, or foam. REMEMBER...the RX-7 has a small engine compartment with minimal exit paths for the hot air to escape from. If the air can’t get out fast enough from the rear and bottom of the engine compartment, it will simply go around the rad or fan to the low pressure area in front, reducing the amount of fresh cool air drawn in. Our radiator kits use the largest possible radiator without requiring major modifications, and our radiator brackets are engineered to seal off the paths around the rad without further fabrication.

Thermostat...Be sure to use a new high quality thermostat that features a balanced design, such as the Robertshaw "extra performance" series. One almost necessary modification to your new thermostat is that a 1/8” diameter hole should be drilled thru the flat area of the disc to allow more thorough purging of any air bubbles when adding coolant. This mod also makes the process much faster, as the bubbles can now travel thru the closed thermostat into the upper radiator hose.


RX-7 Fuel System...

Carbureted applications...If you are using a carburetor with your conversion, a fuel supply loop should be plumbed in to make the hi-pressure RX-7 fuel pump compatible with the low pressure / volume requirements of your carburetor. The RX-7 fuel pump must have a constantly circulating fuel flow through it for cooling purposes. To make both the carburetor and fuel pump happy, we install a “T” into the fuel line, connecting the pressure and return lines together, to form a path for the fuel to circulate back to the fuel tank. The 3rd leg of the “T” should go to a fuel pressure regulator (available at any auto parts store), then on to the carburetor. Plumbed like this, fuel will just return to the tank through the return line without building any pressure for the carburetor. In order to get the 4-6 psi pressure recommended for the carburetor, some restriction is needed in the return line. An easy way to get this restriction is to use a pair of “Vice Grip” type pliers, and slowly and incrementally crimp the steel section of the return line until there is about 8-10 psi before the pressure regulator. After this is achieved, the regulator can be adjusted to further drop that pressure to 4-6 psi for the carburetor.

Injected applications...The stock RX-7 fuel pump is compatible in both pressure and volume for all but the most modified Ford EFI fuel injected V-8 engines (injected RX-7’s typically run about 45 psi of fuel pressure at the injector). Since the pressure regulator is located on the end of the engine's fuel rail, fuel pressure is automatically adjusted to the requirements of the engine.


RX-7 AC System...

Re-plumbing the RX-7's AC system is easier than one might think. We suggest that you re-use the OEM hose fittings/pipes from the RX-7 at the firewall, condensor, and drier. Re-use the OEM hose fittings for the compressor that you are using. Salvaging these fittings will not only save you money, but it will insure that you have the correct fittings for your application. The salvaged fittings will be fitted with new hose and crimp sleeves, and hose length and fitting angle can be adjusted to your exact requirements. The AC system plumbing should be routed as follows...
...large firewall fitting connects to the compressor suction port.
...small firewall fitting connects to the reciever/drier outlet port.
...compressor pressure port connects to top of the condensor core.
...condensor core bottom connects to the reciever/drier inlet port.
After the hose lengths and fitting direction are tailored to your application, return to the hose shop to have your new crimp sleeves crimped onto your new hoses permanantly.
After the hoses are attached, you can take your car to the AC shop to evacuate and charge the system.
If your completed AC system is operating under severe conditions, a small 10" fan can be attached to the condensor core to boost performance.
The electrical part of your engine conversion for the AC system is covered in the electrical section.

Next page....

1....Introduction....

2....Considerations & Requirements....

3....Getting Started....

4....Engine / Transmission Installation....

5....Exhaust / Throttle Cable / Accessory Drive / Pulleys....

6....Cooling / Fuel Systems....

7....RX-7 Wiring Harness Connector ID and Circuit Locations....

8....Electrical System Modifications By Circuit....

9....Start-up / Troubleshooting....

10....Upgrades....

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