Autogauge Stepper Motor Series and Smoked Series Gauge Install and Review

From left to right: Oil temp, Oil pressure, Water temp.

The Oil temp gauge is an Autogauge Stepper Motor Series and the other two are Autogauge Smoked Series.

The Stepper Motor Series does the whole Defi start up ceremony where the needle does the full sweep and the lights flash upon start up. It also makes a loud, prolonged beep noise upon start up which can be a bit annoying. The Smoked Series are silent on start up.

Prior to fitting

The Stepper Motor Series oil temp gauge has a small white (2mm or 2.5mm allen) calibration screw at the back of the gauge. So before I installed the gauge to the car I checked the calibration by hooking it up to a spare car battery I have and placing the sensor in a pot of water. I boiled the water and adjusted the screw so that the gauge would read 100 degrees Celsius to ensure accuracy.

The Smoked Series do not have calibration screws, at least not exposed in its case - I have not opened them up to inspect internally.

The Install

First, I checked the combined current draw of all three gauges with a multimeter and found that it is around 0.3 - 0.4 amps. This was surprising as I was worried I'd have to split the wiring for the three gauges to spread the current draw to prevent exceeding the amperage rating of the 180sx's interior electrical circuits (eg cig lighter, audio unit, etc). I can't guarantee that this is the case for all after market gauges so check the current draw of your particular gauge!

With this knowledge, I tapped into the wires of the audio unit power supply: Permanent 12V (battery+ive), Accessory, and Illumination. And earthed it to the body. 

Automotive 8Pin connectors are your friend here:

Illustration from the Narva Website

What you have is three gauges, meaning three earth wires, three +ive, three sender wires etc etc.

You need to combine each category into one pin. Each pin of the Narva connector is rated at 20amps so its more than enough to handle the current draw of these gauges.

Note: the stepper motor series has a permanent 12V+ wire for peak recall memory so you'll need add that, if you are just installing the smoked series then the above diagram can be followed 100%.

This is the neatest way to install these gauges. Hard wiring them by soldering the wires into your existing electrical circuits means you need to cut the gauge out if you wanted replace them or remove them for whatever reason. Using connectors means you can replace each gauge (if one of them fucks out) efficiently and neatly - just like factory.

Senders

Im running a JAB design coolant neck sandwich plate (which is exactly the same as the Gktech coolant neck sandwich plate [I believe is a "JAB" design originally]) for the water temp sender and a Shadow Pro oil filter sandwich plate for the oil temp and pressure senders. Best thing for pressure senders is to isolate them from vibration - that means installing it OFF the engine (ie on the body somewhere) and use a braided oil line coming off the sandwich plate and onto the sender. This will prolong the life of your sender unit. 

Use thread sealant (I used Permatex thread sealant and it seems to work quite well) for all the sender threads.

Sandwich plate between head and coolant neck. (Easier to view if you download the image and zoom in)

Pressure sender mounted remotely. I still need to get a braided line 1/8NPT male and female fittings.

Completed Install:

Ultra Racing Fender Braces - Full Review

Fitment:

Not an easy job. Fitting these took me about 7hrs altogether. This is not ultra racing's fault. But the fact that I had to fuck around with the big wiring harness underneath the wheel arch and short circuited the indicator circuit.... Also takes a few goes to line the door back up again.

The braces themselves are relatively high quality. The welds are decent, however the cuts on the end plate (the plate that is bolted to the fender frame) are rather sketch... as illustrated in this pic:

Ahh I was being a bit negative there.. The braces aren't something I'd want to be making myself, as there are some funky bends here and there and some tight bracket work to make them fit. And credit to the fabricators at ultra racing because they fit rather well. So for $160 posted to your door I'd save yourself the stress and just go and buy a pair. Fitment requires drilling of two holes for the end plates and also bend a small body extrusion from the car in this area:

Driving Impression:
 I hope it wasn't my head fucking with me because as soon as the moment my car twisted down my driveway it felt different. There was waayy less twist and it hopped off the gutter much more solidly.mGoing up my road and over familiar bumps the car felt bumpier, the front end generally stiffer.. This was fucking good and I hadn't even begin to hit the corners yet!

As I threw the car into various corners, S bends, off camber, on camber, etc the car showed more sign of oversteer than before. I'm entering corners on the overrun, 0% throttle, and the tail just tucks around the corners... like the optimum slip angle I'd like to think..haha. The front end just stays so planted, understeering is a thing of the past. I knew that S13's have flex issues especially in the front fender area but I can't believe how much of a difference these things make on an S13 chassis. Pretty sure these improvements are not psychological in proportion to the amount of time and effort I spent on fitment.. lol

I recommend this modification to anyone.
The results achieved from fitting these will differ depending on alignment settings, sway bars, spring rates, etc. So keep that in mind - you might not get increased oversteer like I did. The objective here is to achieve ANY difference because it means that there definitely is handling-altering-flex at the front quarter of the S13's.

The issues you'd come across is the location of the wiring harness under the RHS fender.. and the ride becomes a bit bumpier. You dont have to relocate the wiring harness but to get your car to any decent level of lowness subjects the harness to some high level of tyre rape. And you really don't want to be risking this because its a head fuck to fix if it fucks out. I just pulled mine over the fender brace, got rid of the thick conduit and used felt tape to insulate it so that the fender (standard fender) would still fit. Clearance is tight here. Sorry I don't have a photo of this.