Stevo

I really love this site: http://123d.circuits.io/

Used to be circuits.io

You can get started prototyping circuits and drawing up schematics without downloading any software. It is all modern web technology in the browser!

I am by no means a professional EE, so if you see anything here that is not up to standards (and you see what I'm doing wrong) please feel free to tell me.

I don't sell these things and I don't intend to.
If you want to try and reproduce my setup, I can help you with that.

Highlights

• The easiest MOSFETS to use are going to be the Fairchild FQP30N06L https://www.sparkfun.com/products/10213. This is a good tutorial on how to implement these switches

...

1)https://en.wikipedia.org/wiki/Pulse-width_modulation
2)http://arduino.cc/en/Tutorial/PWM

While learning about PWM manipulation, I also discovered a really cool related project http://www.arduinodev.com/hardware/obd-kit/.
Basically, this device allows you to connect an Arduino in and immediately (after some minor coding) read the values via standard OBD-II protocol based interfaces. Some example values are: RPM, throttle position and calculated engine load. There are ...