kelsey_canard:
Thought I would do a little update on this. After further reading, I think my biggest struggle will be with the electronics of arduino. For example: MOSFETs, resistors, power supply, etc... Still looking for for the best arduino kit to start with. This is on my top so far:
Budget Pack for Metro 328 - with Assembled Metro ATmega328P : ID 193 : Adafruit Industries, Unique & fun DIY electronics and kits
That's actually probably a good kit to start with; nothing too fancy - enough basic parts to get your feet wet with. Get something like that, and play with it until you understand how everything is working and why. Then you can move on to other parts.
kelsey_canard:
Any other reccomendations? I've got a radio shack local, but that is the extent to my electronic products that are readily available. Just wanting everything I need to get started and not break the bank if I crash with this whole thing.
That kit above will give you enough to learn how to read a sensor (like an LDR, potentiometer, or switch) - which should be enough to help you understand how to do the same with the sensors on your car (or from OBD). Output, though, is kinda lacking (your only option with the kit looks like LEDs or the serial port). Still, that's enough to learn how to understand sensor input, and change the output of something in response.
Later, you're going to want to learn how to control something to move that wastegate; for that, I am not sure how well a solenoid would work - most of the time, solenoids are on or off, though perhaps with PWM control you can make it move to a certain point - but how well it will hold that position is up in the air (unless you have some way to sense the position of the angle the wastegate is at). You might want to look into a servo control system (though how well a standard R/C servo will stand up to an engine compartment is anyone's guess - shop carefully!). Or, you may want to build your own servo control system with a DC gearmotor, a potentiometer to monitor the angle, and an h-bridge to control the potentiometer.
Moving the wastegate isn't the issue here - monitoring it and providing proper servo control - so it always stays at the same angle regardless of vibrations or other issues trying to shift it - is more difficult. But not impossible; just take your time and research the problems - break each problem into smaller ones, and tackle them independently until you understand and solve them. And of course ask around here for help.
As for electronic parts - Radio Shack should be a "last resort" kind of place; they really aren't the place they used to be back in the day. Instead, shop for parts on Ebay (if you don't mind the wait) - or go thru Adafruit, Sparkfun, and other online stores (there are an absolute ton of them, ask around here or do some research on here for more options).
I personally like surplus; great for those personal "one-off" projects that you don't intend to replicate or sell. My favorite places:
http://www.allelectronics.com/
http://www.goldmine-elec-products.com/
That last one has something interesting I always like to recommend to those just starting out (some may say I am evil for it, though) - check out this product:
http://www.goldmine-elec-products.com/prodinfo.asp?number=G9321 (they also offer a smaller version)
Basically, it is a box of tons of electronic "floor sweepings" - they really aren't, but that's the derisive term. You'll find a ton of strange and wonderful parts in the box; in many cases you'll find enough quality parts that more than make up for the cost of the box. Every box is different. Basically, though, the savings come at a cost: You have to sort out the parts - and there is an absolute ton of parts in the box, like you wouldn't believe. Everything from LEDs, to transistors, to diodes, resistors, capacitors, potentiometers, switches, coils, and on and on...
I have a ton of other links for other surplus suppliers (electronics and otherwise) - send me a PM if you think you might be interested. But those three above are ones that I have ordered from often in the past; they are all reputable.