I'm making my own temprature guage, it's goanna be interesting...
Two question before I can complete it:

Where should i put the sensor? The probe will work in water or not, either way it'll get a good reading. I've heard of one's where you monitor radiator temps, and others that are cylender head guages, and there's also pyrometer's. Which do you think will acuratly measure the overall temperature of my engine?

Any comments are welcome. THanks guys


second question: How should I run a wire from the cockpit to the engine bay?

 

What are you measuring? Intake air is colder than coolant is colder than oil which is colder than exhaust gas. You have to pick one because there are several different temperatures that can be read. Personally, I think either oil temp (for turbo setups) or EGT gauges are the most useful. The car already comes with a water temp gauge, so don't waste your time. If you have a turbo setup with an intercooler, you could measure the air temp before and after the intercooler to see the efficiency of the intercooler. I personally wouldn't make one, but just save myself the hassle and buy an autometer one off ebay.

You have to send the wire through the firewall into the engine bay. I don't know what car yours is, but on mine there was a rubber grommet behind the clutch master cylinder that I poked the wire through with a screwdriver. It comes out underneath the fusebox and it works fine. I have an oil line, boost line, and power wires coming through and the rubber insulates the lines from "chaffing" on the firewall.

 

Thanks so much for the great reply. I have a 98 prelude, I beleive it's similar to an integra in that matter. I'll look around for that rubber grommet.

About the place for the probe, I would rather measure the oil temprature, but I feel that doing so would require a good seal that I couldn't make or feel like buying. Sounds like measuring the exhuast gases will be the easiest option, I think I'll just mount it below the heat shield. Seeing as this is only an expiriment (not anything for tuning the engine), that reading should be fine. My only concerns are that the reading could exceed 300 degrees F, and that the headers might be the hottest place in the engine, giving me an inaccuratly high measurement.

Thanks so much for you help.

I have a feeling I won't be able to find that grommet, knowing my luck, but I'll get back to you.

 

I don't know if the grommet is in the same place on yours as it was on mine but look around as there are probably several ways to get through.

You definitely won't be able to use that 300 degree thermometer on the exhaust gas measurements as they get as hot as 1500 degrees. Oil temperature wouldn't be too hard if you had the right connecting hardware to tap into the oil pressure sensor behind the engine block. I have my oil feed line and my mechanical oil pressure gauge tapped into the sensor at the moment. You also might be able to get a probe welded into the oil pan and can measure it that way. Water temp isn't hard either.

I am just trying to figure out why you are going through this trouble for just an experiment. If there were a useful cause, it would make sense but I would rather spend my money and time on something that I know is going to do something productive. Just my 2 cents.

Good luck though and if you need any more ideas or tips, let me know.