240Z Headlight Upgrade Harness

240Z HLH $125

The Datsun 240Z never came with relays for the Headlight circuit. Because of this, the headlights dim, wiring overheats, fuses get hot enough to melt the plastic of the fuse box and the headlight switch (Combo switch) typically fails due to high resistance in the circuit.


This harness reduces the amperage that normally runs thru the combo switch, fusebox, wiring and other connectors by over 98%. This is possible because the relays only require 0.25 amps to connect power from the battery, directly to the headlights. The circuit, without my harness, normally has aprox. 20+ amps going through it.


My 240Z Headlight upgrade harness is a simple "Plug & Play" harness built just for the 240Z. The relay pack mounts to the right fender using one of the Voltage Regulator screws. The Fused Power wire is black and blends in with the factory engine harness and bolts to the Battery's Positive post. The rest of the harness goes through the radiator support wall and connects to the headlight connectors located in front of the radiator, to the left and right.


Simply unplug your headlight connectors (they're 3 wire connectors with red colored wires) connect the Upgrade harness into those open connectors, bolt the new ground wire to the inner frame using the old Lower Vallance mounting bolts, then move to the drivers side and repeat the process. Instal the "False" plug that comes with the kit, into the open engine harness side connector and you're done.


Once installed, you will not only have True battery voltage to the headlights again, probably for the first time in 30 years, but you can now upgrade to H4's up to 90/100 watt bulbs without ANY issues or problems in the headlight circuit. The 240Z HLH is $125 shipped in the Continental US.



Parking Light Upgrade Harness for the S30 up to late 1976

PLH available in 6 or 9 pin $50

Working on the same principal as the Headlight upgrade harness, the Parking light upgrade harness will plug right into your S30's combo switch as a "T" harness and no cutting of existing wiring is needed. The relay and it's ground wire mounts under the steering column using one of the steering column support bolts. The Kit comes with a 6 foot long, 12 gauge, fused power wire that connects to the battery's positive post and goes through the firewall and over to the steering column.


This kit only takes about 30 minutes to install and will brighten the Dash lights, front and rear parking lights and the sidemarkers. The Parking light fuse in the fusebox is usually the first one to melt or show signs of overheating. The amperage flowing through that fuse, the combo switch contacts and all the associated wiring and connectors will be reduced by over 90%. Almost all customers have seen a significant increase in light output after installing the PLH. And for those with little increase in lighting, the PLH was actually built to decrease the amperage thru the system, the brighter lights are just a great side effect.The 6 and 9-pin PLH are $50 shipped, in the Continental US


IF YOU OWN A 77'-78' 280Z, I offer a "Hard-wire version of the PLH that only requires you to cut one wire. Instructions of this wiring come with the kit. The HW-PLH is $40 shipped



240Z Sidemarker Conversion Plugs

SCP Conversion Plugs $25 pair.

The 240Z sidemarker Conversion Plugs turn your front sidemarkers into sidemarker / Blinkers. The 240Z's front turn signals are under the front bumper. They are not easily seen by drivers to your right and left, especially taller vehicles. These simple plugs allow your sidemarkers to blink with the turn signals for a more modern, safer driving experience.






To instal them, just unplug your front marker/turn signals (3-pin plug with green colored wires) plug the SCP into each side, disconnect the black ground wire from your front sidemarker and plug that black wire into the SCP's bullet connector.


*Before You Use Them* Use an Ohms meter to make sure that your sidemarkers are isolated from the body of the car. Before you connect the sidemarker's black wire to the SCP, unplug the 2 sidemarker wires, connect your meter to the Black wire and the other test lead to the body of the car. You should have NO reading or connection between the ground wire and the body.  If you do, make sure the metal body of the sidemarker is mounted properly in the rubber body mount (sitting in the lip of the rubber, not on top or between the rubber and body of the car)


If you remove the 2 screws one at a time and see the connection break, then you might want to widen the holes of the sidemarker body so that the screws go through the rubber without touching the body of the sidemarker. Once the sidemarker no longer shows a ground, then reconnect the sidemarker to the correct wires and the SCP. Then test.

The SCP kit is $25 shipped in the Continental US. The SCP comes with full instructions on ground isolating and installing them.



240Z Alternator Upgrade Plug (ZXP)

ZXP Alternator Adaptor plug $15 ea.

 The 240Z alternator upgrade plug allows the 240Z's weak 40 amp alternator to be replaced with a 50% higher output (60 amp) Alternator from the 81' to 83' 280ZX. The 280ZX alternator is an Internally Regulated alternator, where as the 240Z needs the external regulator.  So when the ZX alternator is installed in the 240Z, the Voltage regulator must be bypassed and the now open connections at the Voltage Regulator plug must be connected to each other properly.


 The ZXP does all the required connecting in a clean, simple plug. The ZXP introduces a Jumper and a Diode that must be installed to prevent ignition feedback, which will power the ignition with the key in the off position.


This is a 240Z ONLY Upgrade! The ZXP will not plug into the 260Z or 280Z.


*WARNING* This adaptor should only be used on the Pre-73' 240Z's that DO NOT have a Stock Electric Fuel pump and Dual Relay set-up typically found on the mid to late 1973 240Z's. Those 240Z's Voltage Regulator's control the Fuel Pump Relay. Bypassing the Voltage Regulator and using the ZXP will Power the Fuel Pump Relay, but will not send power to the fuel pump. This causes a slow battery drain and leaves the relay in the ON position, causing it to overheat and drain the battery.


If you still want to use the ZXP in the above mentioned 73' 240Z, Please contact me and I will send you info on how to control the fuel pump relay via the ignition or an "Oil Pressure Controlled Switch"