All the cool kids are doing it..., Low budget progress thread (Slow Race prep.) Options

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Well, with all the work that I'm doing to my car lately, I might as well start my own progress thread.
Backstory
I bought 4702912742 from my pops about a year and a half ago for $600 dollars, but it wasn't a steal. It had been sitting for about five years and needed a lot of work. He A couple years later he had been looking for a teener for a little while and picked this one up cheap at a dealership in Pomona Ca. He drove it for a while, but it had tons of problems, and soon he decided to sell it. However, the person who test drove it blew first gear, and out to the back yard it was sent.
Fast forward five years to when I was financially ready to get a car to start racing. Long story short, after deciding that I wanted the 914 instead of an older Miata, I told him I was interested. He said that if I bought him a set of mufflers for his bike, we'd call it even.
After that I spent about another 4K just getting it drivable. I replace all four rotors, rebuilt all four calipers, replace the brake lines with braided steel, replaced the hard lines that I broke, replaced the master cylinder, resealed the motor (after my socket and extension locked the motor up), bought two trannies for it (the first one was no good), put a new clutch and pilot bearing in it, put new rubber on the ground (Khumos), fixed and lubed all kinds of latches and hinges to be able to get into all the various compartments, replaced most of the vacuum lines and fuel lines.... the list goes on.
These were all just stock replacements to get it running well. I further had to fight with the injection system for a few months until I figured out that I had it hooked up wrong. (IMG:style_emoticons/default/headbang.gif) Of course, this is the very abbreviated version of the story. As anyone with one of these things knows, the words it takes to describe what parts you changed don't even come close to showing the blood, sweat, and yes, sometimes tears that you put into your work. But anyways, it is running decent now (the motor is still a little tired) so it's time to do some improvements. After all, racing is what I bought the thing for. So I'll try to bring anyone who cares up to date on some of the things I've been working on.
Mark D.

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So this is what I was up to this week. See, last weekend I was asking my dad questions about oiling systems for the engine I'm designing (top secret!), and somewhere in the conversation he said something about having a safety wired into the thing to where when it loses oil pressure it kills the ignition. I thought, "Hey! That'd be a really cool thing to do SOMEDAY." That was last weekend, and 'someday' turned out to be this weekend! (IMG:style_emoticons/default/biggrin.gif) I got to thinking while taking a cruise in the 914 that there's already a switch that kicks on upon VERY low oil pressure, for the idiot light! Well, my idiot light doesn't work, but I do have the dual sender for my oil pressure gauge. So we started figuring it out.
I first had to decide if the range was right for the pressure switch. Namely, would it kick off at a low enough pressure that it wouldn't interfere with daily driving, but a high enough pressure that no major damage would occur before it shut off. I looked up the VDO part # for the dual sensor and found out that the light is supposed to turn on at 11.4 PSI. It sounded about right, so I figured I'd go for it. There was also a 7.4 sender in case the shut-off interfered a lot.
This made me think it was possible, so my dad and I went about drawing some wiring diagrams. He's done automation controls on all kinds of stuff for years, so he was a big help on the relay logic.... Oh, who am I kidding. He just drew it up and I watched! (IMG:style_emoticons/default/biggrin.gif) What I wanted was for it to interrupt the lead from the ignition loom to the + side of the coil, light an indicator light, and trip a holding contact to hold the thing off so that you couldn't restart the engine until you reset a manual override. The holding contact is basically a feature to make sure you acknowledge the problem before trying to restart the engine. I'm not gonna bother trying to explain all the relay logic in text because it's just confusing as hell, but I got all that to work on one 8 pin relay.
The only major thing that got changed in the design was that instead of cutting the power to the coil, I ended up interrupting the control to the rear relay board. This is the wire that goes from terminal 8 on the fuse box to terminal 8 on the 14 pin connector in the rear. I knew about this wire because it shorted out on me once and I had to trace and replace it! Without power to this wire, nothing runs! No fuel pump, no ECU, no injection, no ignition. I chose to do it this way mainly because it meant I didn't have to run wires for the coil all the way from the back to the dash (where the relay is) and back again to the coil. It was all just done in the dash from the fuse box. As an added bonus, though, if it ever does kick off on low oil pressure, it won't still be pumping fuel to a fireless engine.
There's a manual override switch right next to the starter switch (toggle right now, but I'm gonna change it to a momentary). You hold the manual override up with the starter switch to start the car and then let it go once it starts. This override shuts the safety circuit off while the engine is at rest (with no oil pressure) and allows the engine to get fuel and spark to start. It also shuts the oil pressure light off. Once I get the momentary switch in, the safety circuit will switch on as soon as you let go of the switch. Right now it's just normally overridden, and you just switch it on after the car starts.
Well, enough talk. Let's get to pictures. This is the relay I used. It was like 8 bucks at Radio Shack, and the base for it (with all the solder in connections) was in my dad's stash! I made a little bracket to tuck it up under the dash. It works, but I'm not real proud of it, so you're not getting a picture of that! (IMG:style_emoticons/default/biggrin.gif)

This is not really relevant to the story, but I seriously need to work on my organizational skills when I'm actually in the middle of a job...... That and the picture is fuzzy! (IMG:style_emoticons/default/dry.gif)

Mark D.