DIY: Oil Pressure Gauge

40 to 332

OK, a few comments to start:

1. In terms of the installation of the thermostatic plate, you are correct. The side with the rubber o-ring should be mounted against either the upper oil pan or the factory oil cooler depending on the model year of the Z. (Earlier Z's were not equipped with the oil cooler). The oil filter will screw into the opposite side of the plate. Even with the plate installed, there should be enough space for the oil filter.

2. In terms of the fittings, I would recommend applying a small amount of Permatex high-temperature thread sealant (or an equivalent brand-name sealant) to the threads as opposed to using teflon or threadlocker. I've found that the Permatex sealant works well. That said, follow the manufacturers' instructions. If they say to use teflon, use it.

3. In terms of the sensor fittings, it's important to recognize that different thread types exist. The most common ones are NPT and BSPT. They have different thread pitches and are not interchangeable. The port in the engine block where the factory sensor is mounted is a BSPT thread type. You will need to determine the thread type of your T-fitting as well as the aftermarket sensor. It is important that the thread types match. Adaptors are available that allow "bridging" between fittings of different thread types.

4. In terms of the wiring, I would recommend running the sensor wires through the large rubber grommet located in the firewall behind the battery. Afterwards, make sure to apply some silicone or RTV sealant around the opening that may need to be created to feed the wires through. Once inside, you can run the wires to the gauge, wherever you decide to place it. In terms of the gauge wires, I'd recommend running them to the driver's footwell where you'll find a fuse box. Connect the load wire from the gauge to an "add-a-circuit" (or fuse tap) of suitable amperage that you can install in the fuse box. You can select what circuit you want to tap into. The ground wire from the gauge can be connected to a nearby grounding surface, such as a screw or bolt mounted into metal. Make sure to disconnect the battery before proceeding with the wiring.

Trust this helps!