1998 Honda Civic - Fuel The Fire - Project Civic

Now that Project Civic has started to take form, it’s time to work on dialing in the specifics. I want this car to be fun to drive on track, meaning I need to be comfortable and informed of the car’s condition as much as possible and doing everything I can to ensure that it runs properly and efficiently.

I decided that a few gauges would help ease my mind, while adding a nice bit of visual flare at the same time. The parameters I’m most concerned with for my NA Civic are water temperature, A/F ratio, oil temp and oil pressure. But before I get to the gauges, I decided to upgrade my factory cooling system. Koyorad supplied me with its high-capacity replacement radiator, a massive improvement over the stock Civic unit. Koyorad radiators are constructed of 100 percent aluminum and feature welded end tanks, while maintaining factory fitment. The fit is tight, but that’s mostly because the 53mm thickness of the Koyorad unit is a lot more than the stock radiator. Increased core thickness allows for higher cooling capacity and, theoretically, lower engine operating temperatures. Another nice thing about the Koyorad units is their ability to use the stock fan and shroud if you so desire.

With the new radiator in place, I turned my attention to how I planned on monitoring water temperatures. While the Civic obviously has a factory water temperature gauge in the dash like nearly every car, I wanted something a little more accurate. To get the most relevant readings, I turned to Phase 2 Motor Trend for a set of its S Gear water temperature, oil temp and oil pressure gauges. These gauges are extremely clean looking and feature 280-degree stepping motors to ensure accurate readings. Each gauge includes all required wiring and sensors, as well as detailed installation instructions. To monitor my A/F ratio, AEM has supplied me with its analog wideband, which includes a Bosch O2 sensor and all required wiring. Because the AEM wideband doesn’t include a pod of any sort to mount the gauge, I had to get creative. More on that later.

I decided to place my water temp sensor near the upper neck of the radiator between the rad and engine block. The easiest way to get a sensor in this location is to use a water hose sensor adaptor; Buddy club offers a 30mm sizing, which is correct for Hondas of my era.

For the two oil sensors (temperature and pressure), I decided to go with the common and effective solution of an oil filter block adaptor from BLOX Racing. This simple billet piece mounts between the engine block and the oil filter, providing several provisions for different purposes. Installing this piece is straightforward — just thread it on between the block and filter, make sure it’s tight (no leaks), and you’re ready to go.

To monitor the A/F ratio, it’s necessary to weld a bung into the exhaust path. The test pipe seems like a good spot for it, and after a few minutes on the cutting table, head honcho Peter Tarach cleanly and securely welded the necessary provision for the additional O2 sensor in place, and we were in business to begin wiring everything up.

The new radiator is ready to go in. Note how much thicker the core is than the stock Civic rad; there’s no question this will help increase cooling capacity.

The new radiator is ready to go in. Note how much thicker the core is than the stock Civic

My Civic’s engine bay isn’t exactly what we would call “show quality,” meaning the wiring harness isn’t tucked. I wanted to make sure the wiring for my gauges was efficient and safe, and wouldn’t interfere with anything that’s already in the bay. A few zip-ties, and I had the wires attached and out of the way. So where do they go into the cabin? Just below the battery tray there was an open provision in the firewall, filled with a rubber grommet. By taking out this grommet and cutting a small hole in the middle, I was able to run the wires through the grommet and maintain most of the sound deadening it provides.