I want to wire in an LED light that mounts in the A-Pillar pod with the water temp and oil pressure guages. I have an electric water and mechanical oil, but I have the stock oil still hooked up so I can use it for this.

Im guessing these guages just work off of Ohms of resistance from the sending unit and it calculates it from there. So in theory you could figure out what the resistance is at say 200 degrees water temp and put a resistor inline with an LED light so that when it goes past that resistance the light turns on, and same thing with the oil pressure at say 15 psi or something. I just dont look down at my guages as often as I should and I cant keep my eye on them at the track when im trying to drive and shift, so I figure a bright red light will catch my attention out of the corner of my eye letting me know when im in a danger zone.

Question is, is this possible, and would someone be able to figure out these resistance values for me so that I can get this wired up, I dont have a engine right now...

 

Tada
Not sure on how it installs but it gives you something to look into...

 

Not sure what your asking but if you want an oil light to come on , why not use a oil pressure switch for a light.

The switch provides a ground with no pressure.

Once oil pressure comes up , it goes open.

Never heard of one at a certain pressure to turn a light on.

The gauge units a varible resistors , that would only vary how bright the light got.

Temp senders are thermistors.