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Intalling a light that increases in brighness when rev

Posted: Thu Jun 05, 2014 1:24 am
by CatmanFS
I know this is going to sound crazy but I wanted to put a light of some sort under the hood of my car that would get brighter when I rev the engine. The desired effect is that the engine bay, the ground, and seams around the body would be illuminated when the car revs up. I know this is kinda silly, but I just wanted to play around with a few ideas and see if I could get this working.

I figured that working with the alternator would possibly give the kind of returns I'm looking for, but I'd have to have some kind of resistor to keep from blowing the bulb.

Any ideas?

Re: Intalling a light that increases in brighness when rev

Posted: Wed Jul 09, 2014 12:16 am
by techweenie
Find a way to piggyback a generator to the accessory belt and wire in a bunch of LEDs or something. You'd of course need some regulator circuitry, but shouldn't be hard for anyone into electronics to work out.

Re: Intalling a light that increases in brighness when rev

Posted: Fri Jul 11, 2014 12:43 am
by Evilcowboy420
basically your trying to make a dimmer switch and use the throttle to control it. Weather you want to make the dimmer part or just buy one from a store which would be easier and just wire a circuit for fading led's. You would definitely want to protect whatever circuit you make.


Here's what I would do personally. I would get a dimmer switch manually hook it so either the throttle cable worked it (depends on size) or the pedal in the car worked it. Then I would wire a relay into the circuit to switch the circuit on after the car had started (this will ensure your not putting extra strain on the battery until after it had started) or hook it to a manual toggle in the car if you didn't want them to constantly run. Then throw a inline fuse in the circuit to protect the dimmer and the lights so they don't burn up if something goes wrong. For lights a 20A switch and 20A fuses should work just fine since it's not a huge draw you should be able to find a 20A dimmer as well.

Anyway thats my idea. good luck with your mod.

Re: Intalling a light that increases in brighness when rev

Posted: Fri Jul 11, 2014 7:21 pm
by corvettecrazy
You can do this many ways. All of the ones above with hooking into the alternator and such seem like a giant recipe for electrical trouble.

I would start with an arduino.

You can get your signal many ways. OBDII bluetooth module, OBDII arduino reader, tapping the tach signal wires.

Once you have that signal it is very easy to program output pins to adjust output of lights. You could even have the lights change color and brightness with different RPM.

WS2812 LED strips and you are off and running.