....Exhaust / Throttle Cable / Accessory Drive / Pulleys....
EXHAUST...
...The rest of the exhaust system is best left to the professional. The best underbody exit path for the exhaust that maintains maximum ground clearance is down along the passenger side of the
transmission tunnel. A good smog legal plan would route the driver's side 2-1/2" pipe,
joining the passenger side 2-1/2" pipe in a "Y" in the starter/bellhousing area. The exit of the "Y" would be a single 3-1/2" pipe thru
a single hi-flo catalytic converter (positioned to use existing RX-7 heat shields), which is then routed over the axle to a large packed muffler mounted in the stock location. Beware of chambered mufflers w/o packing, as they can cause a bit if resonance inside the passenger compartment at highway
speeds.
THROTTLE CABLE...
ACCESSORY DRIVE BRACKETS & PULLEYS...
Alternator...
Power Steering...
Air Conditioning Compressor...
2....Considerations & Requirements....
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....
Option #1- stock exhaust manifolds...Stock 5.0 Mustang and Lincoln Mk7 exhaust manifolds will fit. Aftermarket shorty style replacements generally fit, as long as they are not the "ball-of-snakes" equal length upgrades that will interfere with your brake booster.
Option #2- Headers...Early Mustangs have a steering box location similar to your RX-7, but they generally hang too low and typically run into your passenger side floorboard.
For a carbureted engine... a universal throttle cable can be used, along with a bushing to adapt to the throttle arm of a Holley or Carter/Edelbrock carburetor. An optional method is to use a throttle cable from a '80's/'90's Camaro, which can be easily adapted to the RX-7 firewall / throttle pedal using a short spacer.
For an injected engine... the stock 5.0 throttle cable can be easily adapted to the RX-7’s throttle pedal with
the spacer at the pedal end of the cable.
...Because your Ford engine likely came with a serpentine drive system, we suggest using the stock Ford alternator, power steering pump, and AC compressor. Much better/easier to make custom hoses than to change back to a v-belt.
Just use the Ford alternator in it's stock location.
Your Rx-7's steering gear can be plumbed to the Ford's PS pump using custom hoses. Your RX-7's PS hoses will most likely screw right onto your Ford PS pump, but you will need new rubber hose between your old fittings to get the right lengths. Just salvage the fittings from your existing hoses by slitting the "crimp sleeves" that secure the hos to the fittings. Get new rubber hoses and new crimp sleeves from the hydraulic hose shop. Assemble your fittings/hoses/crimp sleeves on the car to get the lengths and fitting angles perfect, then take the hoses back to the hydraulic shop to get the crimp sleeves set. This gets you new custom hoses that fit perfectly for the price of new rubber and crimp sleeves.
The Mazda box can be plumbed into the Ford pump as follows...
...Pressure hose- this is the pressure line from the pump to the steering box. Plumb this hose directly to the Ford pump's pressure fitting using a custom fabricated hi-pressure hose.
...Low pressure return hose- this is the return line from the steering gear back to the Ford pump's resevoir.
Use the Ford AC compressor in it's stock location. Re-use your existing fittings and combine them with new rubber and crimp sleeves using the same general method used for making the custom PS hoses listed above.