RX-7 ENGINE CONVERSION ELECTRICAL INFO

Conversion wiring requirements for your RX-7 may vary quite a bit depending on the year of car and the components used.

'79-'80 MODELS

The conversion requiring the least effort with regards to electrical wiring would be an early 1st gen RX-7 using a carbureted V-8, a point style distributor, and the stock RX-7 alternator and instrument sending units. The stock rotary ECU (located to the left of the clutch pedal) and the relays and solenoids in the engine bay that are attached to it are no longer needed. The heater, wiper, lites, etc will not be effected. The unnecessary switches and relays under the hood can be eliminated and the leftover wires trimmed back or covered for a neat appearance.

EASY PLACES TO MAKE CONNECTIONS...

Connector X-01 The RX-7's Engine harness connects to the Front harness at X-01, a rectangular 22 conductor plug (2 rows of 11), located between the left front strut tower and the brake master cylinder. Listed below are the wires of interest that can be accessed at this connection:
Black w/ white stripe...there are 2 of these wires, which are 12v+ when the ignition is on. A good source for power for your V-8's ignition system.
Yellow w/ red stripe...this wire used to go to the oil level sensor on the rotary engine. When this wire is grounded, the oil level warning lite on the dash will come on. You can connect this wire to a Chevy (or Ford) oil pressure warning lite switch, and your RX-7's oil level warning lite will come on with low oil pressure.
Yellow w/ white stripe...this wire connects to the RX-7's stock water temp sender, and operates the water temp gauge in the dash. Use an adapter to install the RX-7 water temp sender (a small sender located below and in front of the oil filter) into the Chevy/Ford engine.
White...this wire is the RX-7 alternator's ground wire, which connects to the alternator's "E" terminal thru the small 2 conductor plug.
Black w/ yellow stripe...this wire also connects to the stock RX-7 alternator thru the small 2 conductor plug, and connects to the "N" terminal.
Black...this wire is one of the harness grounds, and should be connected to the engine block.

Connector X-12 The RX-7's Transmission harness connects to the Front harness thru X-12, a rectangular 6 conductor plug (2 rows of 3). The wires of interest here are:
Black w/ yellow stripe...this wire is the one that energizes the starter solenoid to crank the engine over. On the Chevy engine, it should be connected to the "S" terminal on the starter solenoid (the small one closest to the block). On the Ford engine, it should be connected to the "S" post on the firewall mounted starter solenoid.
Green w/ yellow stripe...this wire goes to the backup lite switch on the transmission (manual trans), or the shifter (automatic equipped cars).
Red w/ white stripe...this wire also goes to the other post on the backup lite switch.

Connector B-33 The tach signal wire is most easily accessed at the B-33 connector that went to the RX-7's rear coil, located just in front of the left strut tower:
Yellow w/ green stripe...this wire is the tach signal wire.

Connector B-01 The B-01 connector is the rectangular 16 pin (2 rows of 8) connector for non-Calif. cars, or a rectangular 22 pin (2 rows of 11) connector for the Calif cars, that plugs into the RX-7's stock ECU. The stock ECU is not needed, and can be removed when doing an engine conversion. The remaining plug gives you access to the following wires of interest:
Black...this is a ground wire that formerly grounded the RX-7's ECU.
Yellow w/ green stripe...this is another point that you can feed the tach signal into the tach.

'81-'83 MODELS

More electrical options and electronic ignition. Cruise control and air conditioning circuits need no changes. Mazda did add an oil pressure guage. The sender is located below the oil filter

EASY PLACES TO MAKE CONNECTIONS...

Connector X-01 The RX-7's Engine harness connects to the Front harness at X-01, a rectangular 22 conductor plug (2 rows of 11), located between the left front strut tower and the brake master cylinder. Listed below are the wires of interest that can be accessed at this connection:
Black w/ white stripe...there are 2 of these wires, which are 12v+ when the ignition is on. A good source for power for your V-8's ignition system.
Yellow w/ red stripe...this wire used to go to the oil level sensor on the rotary engine. When this wire is grounded, the oil level warning lite on the dash will come on. You can connect this wire to a Chevy (or Ford) oil pressure warning lite switch, and your RX-7's oil level warning lite will come on with low oil pressure.
Brown w/ yellow stripe...this wire connected to the rotary engine's oil pressure sender (a large sender located below the oil filter). An adapter can be used to install this sender in the Chevy/Ford engine to retain the function of your RX-7's oil pressure gauge.
Yellow w/ white stripe...this wire connects to the RX-7's stock water temp sender, and operates the water temp gauge in the dash. Use an adapter to install the RX-7 water temp sender (a small sender located below and in front of the oil filter) into the Chevy/Ford engine.
Black w/ white stripe...this wire connects to the RX-7's alternator thru the small "T" shaped plug. This wire forms the top of the "T".
White w/ black stripe...this wire also connects to the stock RX-7 alternator thru the small "T" shaped 2 conductor plug, and connects to the bottom leg part of the "T".
Black w/ yellow stripe...this wire formerly went to the ECU, but comes from the ignition switch "start" position. It can be connected to the Chevy engine's starter solenoid "S" terminal (the small post closest to the block), or the "S" terminal Ford engine's firewall mounted starter solenoid.

Connector X-10 The RX-7's Transmission harness connects to the Front harness thru X-10, a rectangular 4 conductor plug (2 rows of 2). The wires of intrest here are:
Green w/ yellow stripe...this wire goes to the backup lite switch on the transmission (manual trans), or the shifter (automatic equipped cars).
Red w/ white stripe...this wire also goes to the other post on the backup lite switch.

Connector B-18 The tach signal wire is most easily accessed at the B-18 connector that went to the RX-7's trailing coil, located just in front of the left strut tower:
Yellow w/ green stripe...this wire is the tach signal wire.

'84-'85 12A Carbureted Models

EASY PLACES TO MAKE CONNECTIONS...

Connector X-01 The RX-7's Engine harness connects to the Front harness at X-01, a rectangular plug, located between the left front strut tower and the brake master cylinder. Listed below are the wires of interest that can be accessed at this connection:
Black w/ white stripe...there are 2 of these wires, which are 12v+ when the ignition is on. A good source for power for your V-8's ignition system.
Yellow w/ red stripe...this wire used to go to the oil level sensor on the rotary engine. When this wire is grounded, the oil level warning lite on the dash will come on. You can connect this wire to a Chevy (or Ford) oil pressure warning lite switch, and your RX-7's oil level warning lite will come on with low oil pressure.
Brown w/ yellow stripe...this wire connected to the rotary engine's oil pressure sender (a large sender located below the oil filter). An adapter can be used to install this sender in the Chevy/Ford engine to retain the function of your RX-7's oil pressure gauge.
Yellow w/ white stripe...this wire connects to the RX-7's stock water temp sender, and operates the water temp gauge in the dash. Use an adapter to install the RX-7 water temp sender (a small sender located below and in front of the oil filter) into the Chevy/Ford engine.
Black w/ white stripe...this wire connects to the RX-7's alternator thru the small "T" shaped plug. This wire forms the top of the "T".
White w/ black stripe...this wire also connects to the stock RX-7 alternator thru the small "T" shaped 2 conductor plug, and connects to the bottom leg part of the "T".
Black w/ yellow stripe...this wire formerly went to the ECU, but comes from the ignition switch "start" position. It can be connected to the Chevy engine's starter solenoid "S" terminal (the small post closest to the block), or the "S" terminal Ford engine's firewall mounted starter solenoid.

Connector X-09 The RX-7's Transmission harness connects to the Front harness thru X-09, a rectangular 4 conductor plug (2 rows of 2). The wires of interest here are:
Green w/ yellow stripe...this wire goes to the backup lite switch on the transmission (manual trans), or the shifter (automatic equipped cars).
Red w/ white stripe...this wire also goes to the other post on the backup lite switch.

Connector B-02 The tach signal wire is most easily accessed at the B-02 connector that went to the RX-7's trailing coil, located just in front of the left strut tower:
Yellow w/ green stripe...this wire is the tach signal wire.

Connector B-06 The '84-'85 12A model RX-7s use a fuel cut relay to allow the rotary engine's ECU to control the fuel pump. The relay is located under the dash above the steering column, and has a 6 place connector with only 4 wires leading to it, identified as follows:
Black w/ a white stripe...these 2 wires provide 12v from a switched ignition source.
Blue w/ white stripe...this wire goes to the fuel pump.
Black w/ yellow stripe...this wire goes to the n terminal of the rotary's ECU, and needs to be grounded to make the relay energize the fuel pump. Although simple grounding of this terminal will make your fuel pump operate somewhat normally, We strongly recommend that you ground this terminal thru an oil pressure safety switch, so that the fuel pump will not continue to operate should the engine die, or in case of an accident. Connector C-01 The C-01 connector is located on the back of the dash pod, on the left (driver's) side. Of the many other wires that are there, the '84-'85 models also had a speed sensor built into the speedometer head.
Black w/ red stripe...this is the wire from the speed sensor. It is a reed switch, operated by a rotating magnet at the end of the speedo cable inside the dash pod, so the output is a square wave. The switch cycles open and closed a total of 4 times per revolution, which when combined with the 1025 revolutions per mile of the RX-7, makes a 4100 pulse per mile speed signal. The US standard for speedometers is 1000 rev per mile, which makes for a 4000 PPM signal that is often used by computer controlled engines. The difference between 4000 and 4100 PPM is only around 2%, so further correction is often not required. The other leg of the reed switch is grounded internally, and the signal can be used as a vehicle speed input for engines such as the Chevy LT-1.

'84-'85 13B Injected Models

EASY PLACES TO MAKE CONNECTIONS...

Connector B-29 The '84-'85 13B model RX-7s use a circuit opening relay to allow the rotary engine's ECU to control the fuel pump. The relay is located under the dash above the steering column, and has a 6 place connector with only 5 wires leading to it, identified as follows:
Black w/ a white stripe...this wire provides 12v from the battery.
Blue...this wire goes to the fuel pump.
Black w/ red stripe...this wire esed to go to the rotary's ECU, which sent out 12v+ thru this wire to energize the circuit opening relay and turn on the fuel pump until the airflow meter switch was closed.
Black...this wire is a ground.
Brown...this wire goes to a switch inside of the airflow meter (located ahead of the right front strut tower), and needs to be grounded to make the relay energize the fuel pump. Although simple grounding of this terminal will make your fuel pump operate somewhat normally, We strongly recommend that you ground this terminal thru an oil pressure safety switch, so that the fuel pump will not continue to operate should the engine die, or in case of an accident.

Connector C-01 The C-01 connector is located on the back of the dash pod, on the left (driver's) side. Of the many other wires that are there, the '84-'85 models also had a speed sensor built into the speedometer head.
Black w/ red stripe...this is the wire from the speed sensor. It is a reed switch, operated by a rotating magnet at the end of the speedo cable inside the dash pod, so the output is a square wave. The switch cycles open and closed a total of 4 times per revolution, which when combined with the 1025 revolutions per mile of the RX-7, makes a 4100 pulse per mile speed signal. The US standard for speedometers is 1000 rev per mile, which makes for a 4000 PPM signal that is often used by computer controlled engines. The difference between 4000 and 4100 PPM is only around 2%, so further correction is often not required. The other leg of the reed switch is grounded internally, and the signal can be used as a vehicle speed input for engines such as the Chevy LT-1.
The RX-7 ECU, located on the right side, is no longer needed. All the wires from the ECU to the RX-7 engine and sensors, located mainly on the right side of the engine bay, can be removed. On some cars, the wiper wiring runs in the same harness, so splitting the loom and removing the wiper wiring may be required.

'86-'88 13B Injected Models

EASY PLACES TO MAKE CONNECTIONS...

Connector X-04 The RX-7's Engine harness connects to the Front harness at X-04, a rectangular plug with 6 conductors (2 rows of 3), located between the left front strut tower and the firewall. Listed below are the wires of interest that can be accessed at this connection:
Black w/ white stripe...there are 2 of these wires, which are 12v+ when the ignition is on. A good source for power for your V-8's ignition system.
Yellow w/ red stripe...this wire goes to the rotary engine's oil pressure sensor. Install this sensor into the Chevy/Ford (the threads are compatible), and your in-dash oil press gauge will work.
Black w/ yellow stripe...this wire is the power wire to the back-up lite switch, and simply connects to one leg of the switch.
Red w/ green stripe...this wire connects goes back to the back-up lites, and connects to the other leg of the switch.

Connector X-05 This connector is a rectangular 6 conductor (2 rows of 3) located between the firewall and the left front strut tower. Wire of interest here are:
Black w/ white stripe...this wire connects to the RX-7's alternator thru the small "T" shaped plug. This wire forms the top of the "T".
White w/ black stripe...this wire also connects to the stock RX-7 alternator thru the small "T" shaped 2 conductor plug, and connects to the bottom leg part of the "T". Connector X-08 This connector is a 6 conductor (2 rows of 3) located between the firewall and the left strut tower. Wires of interest here are:
Black w/ white stripe...this wire comes from the starter cut relay (controlled by the anti-theft system), and is the ont that energizes the starter to crank the engine over. It can be connected to the Chevy engine's starter solenoid "S" terminal (the small post closest to the block), or the "S" terminal Ford engine's firewall mounted starter solenoid.

Connector Ba-07 The tach signal wire is most easily accessed at the Ba-07 connector that went to the RX-7's trailing coil, located just in front of the left strut tower:
Yellow w/ blue stripe...this wire is the tach signal wire.

Connector Ba-08 This is a small 2 conductor plug, with 2 large wires, going into the trailing coil.
Black w/ yellow stripe...these 2 wires are a great source for switched ignition power for your Chevy/Ford engine. The power comes thru the main relay from a 40A fusible link.

Connector Ba-01 The 2nd gen RX-7s use a circuit opening relay to allow the rotary engine's ECU to control the fuel pump. The relay is located under the dash above the steering column, and has a 6 place connector (2 rows of 3), identified as follows:
Black w/ a white stripe...this wire provides 12v 15A fused power from the battery.
Blue...this wire goes to the fuel pump.
Black w/ red stripe...this wire esed to go to the rotary's ECU, which sent out 12v+ thru this wire to energize the circuit opening relay and turn on the fuel pump until the airflow meter switch was closed.
Black...this wire is a ground.
Brown...this wire goes to a switch inside of the airflow meter (located ahead of the right front strut tower), and needs to be grounded to make the relay energize the fuel pump. Although simple grounding of this terminal will make your fuel pump operate somewhat normally, We strongly recommend that you ground this terminal thru an oil pressure safety switch, so that the fuel pump will not continue to operate should the engine die, or in case of an accident.

Connector C-01 The C-01 connector is located on the back of the dash pod, on the left (driver's) side. Of the many other wires that are there, the '84-'85 models also had a speed sensor built into the speedometer head.
Green w/ red stripe...this is the wire from the speed sensor. It is a reed switch, operated by a rotating magnet at the end of the speedo cable inside the dash pod, so the output is a square wave. The switch cycles open and closed a total of 4 times per revolution, which when combined with the 1025 revolutions per mile of the RX-7, makes a 4100 pulse per mile speed signal. The US standard for speedometers is 1000 rev per mile, which makes for a 4000 PPM signal that is often used by computer controlled engines. The difference between 4000 and 4100 PPM is only around 2%, so further correction is often not required. The other leg of the reed switch is grounded internally, and the signal can be used as a vehicle speed input for engines such as the Chevy LT-1.

The RX-7 ECU, located on the right side, is no longer needed. All the wires from the ECU to the RX-7 engine and sensors, located mainly on the right side of the engine bay, can be removed. The wiper wiring runs in the same harness, so split the loom and save the following wires:
The wiper wires...
Blue
Black
Blue w/ yellow stripe
Blue w/ white stripe
Blue w/ red stripe
The water temp sender wire...
Yellow w/ white stripe
The cruise control wires...
Green
Green w/ black stripe
Green w/ white stripe
Green w/ yellow stripe

Connector G-06 These 2 connectors plug onto the refergerant pressure switch (located on the right side under the plastic panel in front of the hood latch), in the line between the drier and condensor. Points of interest are:
Blue...this wire comes from the AC thermostat.
Blue w/ orange stripe...this wire needs to be connected to a 12v+ ignition power source in order to power the fan amplifier.

Connector G-08 This connector plugs into the AC main relay, located under a plastic panel in front of the hood latch. Wires of interest here are:
Blue w/ black stripe...this wire is power from the ACC side of the ign switch, fused at 10A.
Red w/ yellow stripe...is from the blower control unit.
Black w/ white stripe...this wire goes to the AC compressor clutch magnet.
Blue w/ white stripe...this terminal/wire needs to be grounded to allow the AC clutch to be energized. It was formerly grounded by the ECU.

'89-'91 13B Injected Models

EASY PLACES TO MAKE CONNECTIONS...

Connector C-01 The C-01 connector is located on the back of the dash pod, on the left (driver's) side. Of the many other wires that are there, the '84-'85 models also had a speed sensor built into the speedometer head.
Green w/ red stripe...this is the wire from the speed sensor. It is a reed switch, operated by a rotating magnet at the end of the speedo cable inside the dash pod, so the output is a square wave. The switch cycles open and closed a total of 4 times per revolution, which when combined with the 1025 revolutions per mile of the RX-7, makes a 4100 pulse per mile speed signal. The US standard for speedometers is 1000 rev per mile, which makes for a 4000 PPM signal that is often used by computer controlled engines. The difference between 4000 and 4100 PPM is only around 2%, so further correction is often not required. The other leg of the reed switch is grounded internally, and the signal can be used as a vehicle speed input for engines such as the Chevy LT-1.

WARNING...If your car came w/ ABS, take special care not to disturb any wiring or plumbing that could effect it's proper operation.

RX-7 MAIN PAGE