450 HP ENGINE CONTROL SYSTEM UPGRADE FOR
1981-89 280ZX/300 TURBO
Additional Steps For 280ZX Turbo Only
This conversion is required when horsepower requirements exceed the limits of the stock injectors and restriction
of the original "flopper door" flow meter. Note that a full knowledge of both systems is required before attempt-
ing this conversion. We assume no responsibility for the content of these notes and their use for this modification.
A logical pin by pin inspection is required by the technician to establish that all systems will function correctly
and safely for the intended use and application. This conversion is not intended for applications subject to spe-
cific emission control requirements and should not be used for such applications.
280to30b.pub
1. If conversion is being done to a 1981 280ZX turbo with crank triggered ignition, a distributor
and drive from a '82 or later is needed.
2. Install the encoder disc from a Z31 300ZX (anyone will work) in to the 280ZX turbo distributor.
Mark which side is up and install in same direction.
3. Unplug and discard the VCM (vacuum control module) it is not compatible with the Z31 ECU.
Idle must be adjusted by adjusting the throttle stop or by adding an adjustable air bypass valve.
4. Follow the diagram for the MAF / Flow Meter plug conversion on next page.
5. 82-83 ONLY: Unplug the Fuel Pump Module. Fuel pump control is now done inside the Z31
ECU and the module is not needed. Also ground the fuel pump ground wire direct to a good
ground, as the pump no longer has a ground with the module removed.
6. At the Fuel Pump Relay connector, cut the black wire about 2" below the relay and solder the
black 2" end at the relay to the white wire with a black strip (see note below) at the relay (do not
cut this wire, you are simply tapping into this wire to get 12V+ to the black wire at the relay. The
harness side of the black wire can be taped up as it is no longer used here.
7. Disconnect the detonation sensor, as it is not tuned to the Z31 ECU and won't function correctly.
8. Install the Jim Wolf Technology modified 300ZX ECU.
9. Six dropping resistors need to be installed on the injector wires coming from the ECU to the injec-
tors (1981 already has dropping resistors and does not need them). Because of the improved injec-
tor timing on the later ECU, the injector wires going to cyl #2 and #5 from the ECU must be cut
and switched with each other (wires from pins #102 and #105 from the ECU). This can be done as
you add the dropping resistors.
10. 1981 only: add a wire with unswitched 12v to pin #114 at the ECU. This retains ECU learned in
formation after key is turned off.
• Note:
• This may actually be a black w/white strip in some cars, it is incorrectly stated in the
Nissan factory manual.
• If it’s White with a black strip, it is 12v+
• If it’s Black with a white strip, it’s switched 12v+
• This does not effect the modification, only that the colors may not be as expected.
1. If conversion is being done to a 1981 280ZX turbo with crank triggered ignition, a distributor
and drive from a '82 or later is needed.
2. Install the encoder disc from a Z31 300ZX (anyone will work) in to the 280ZX turbo distributor.
Mark which side is up and install in same direction.
3. Unplug and discard the VCM (vacuum control module) it is not compatible with the Z31 ECU.
Idle must be adjusted by adjusting the throttle stop or by adding an adjustable air bypass valve.
4. Follow the diagram for the MAF / Flow Meter plug conversion on next page.
5. 82-83 ONLY: Unplug the Fuel Pump Module. Fuel pump control is now done inside the Z31
ECU and the module is not needed. Also ground the fuel pump ground wire direct to a good
ground, as the pump no longer has a ground with the module removed.
6. At the Fuel Pump Relay connector, cut the black wire about 2" below the relay and solder the
black 2" end at the relay to the white wire with a black strip (see note below) at the relay (do not
cut this wire, you are simply tapping into this wire to get 12V+ to the black wire at the relay. The
harness side of the black wire can be taped up as it is no longer used here.
7. Disconnect the detonation sensor, as it is not tuned to the Z31 ECU and won't function correctly.
8. Install the Jim Wolf Technology modified 300ZX ECU.
9. Six dropping resistors need to be installed on the injector wires coming from the ECU to the injec-
tors (1981 already has dropping resistors and does not need them). Because of the improved injec-
tor timing on the later ECU, the injector wires going to cyl #2 and #5 from the ECU must be cut
and switched with each other (wires from pins #102 and #105 from the ECU). This can be done as
you add the dropping resistors.
10. 1981 only: add a wire with unswitched 12v to pin #114 at the ECU. This retains ECU learned in
formation after key is turned off.
• Note:
• This may actually be a black w/white strip in some cars, it is incorrectly stated in the
Nissan factory manual.
• If it’s White with a black strip, it is 12v+
• If it’s Black with a white strip, it’s switched 12v+
1. If conversion is being done to a 1981 280ZX turbo with crank triggered ignition, a distributor
and drive from a '82 or later is needed.
2. Install the encoder disc from a Z31 300ZX (anyone will work) in to the 280ZX turbo distributor.
Mark which side is up and install in same direction.
3. Unplug and discard the VCM (vacuum control module) it is not compatible with the Z31 ECU.
Idle must be adjusted by adjusting the throttle stop or by adding an adjustable air bypass valve.
4. Follow the diagram for the MAF / Flow Meter plug conversion on next page.
5. 82-83 ONLY: Unplug the Fuel Pump Module. Fuel pump control is now done inside the Z31
ECU and the module is not needed. Also ground the fuel pump ground wire direct to a good
ground, as the pump no longer has a ground with the module removed.
6. At the Fuel Pump Relay connector, cut the black wire about 2" below the relay and solder the
black 2" end at the relay to the white wire with a black strip (see note below) at the relay (do not
cut this wire, you are simply tapping into this wire to get 12V+ to the black wire at the relay. The
harness side of the black wire can be taped up as it is no longer used here.
7. Disconnect the detonation sensor, as it is not tuned to the Z31 ECU and won't function correctly.
8. Install the Jim Wolf Technology modified 300ZX ECU.
9. Six dropping resistors need to be installed on the injector wires coming from the ECU to the injec-
tors (1981 already has dropping resistors and does not need them). Because of the improved injec-
tor timing on the later ECU, the injector wires going to cyl #2 and #5 from the ECU must be cut
and switched with each other (wires from pins #102 and #105 from the ECU). This can be done as
you add the dropping resistors.
10. 1981 only: add a wire with unswitched 12v to pin #114 at the
ECU. This retains ECU learned information after the key is turned
off.
