I've made some pretty neat performance products for some of my customer car projects (I think), and I get tickled when I see them complete. I guess I feel smug about that stuff.
I'm probably going to bore a lot of you.
(SPOILER)
One car I worked on was running a big turbo, which meant the original ignition system isn't strong enough. I adapted superior coil over plug system (basically from a Z06 Corvette) to give it a stronger system.
Factory original set up. (The black wires in the center of the engine, and coils on the back on the motor.)
I installed different coils, better wires, etc. (The plate over the left side of the motor, with the black blocks attached to it, and red wires going to the center of the motor. I designed and made the hardware for it all to mount with.
Also, I've made a "coolant reroute" for the same motor. Typically the coolant comes out of the front of the engine. Notice the grey plug and sensor in the metal housing at the front of the motor, with a radiator hose that goes to the top of the radiator at the front of picture.
Factory original setup.
I made a system that pulls coolant from the back of the motor instead. This allows for better cooling, and lets the engine make more power safely. Notice the silver pipe that comes from the back of the motor, along the right side, and then the hose that crosses over the top of the radiator.
The next one is a new intake system. The original facotory set-up is the long, silver log looking thing that is on the left side of the engine. It has that large black tube attached to the front of it that goes back across the front of the engine to the right side into that big, black plastic box. That's where the engine gets air from.
I made something called "individual throttle bodies". Instead of the engine getting all of it's air fed into that big silver log from that one source (the black tube.), I adapted an system off of a motorcylce that uses 4 separate intake tubes for each individual cylinder. This lets the motor breath easier, and make a little more power. Plus it keeps everything balanced. I designed to keep an extra set of fuel injectors as well, so we can run two different fuel types for different performance situations.
Sorry to ramble!