Failures in Circuitry

We printed out the wiring diagram and kept it nearby while working on this. Laptops have a tendency to fall off of things and smash into pieces. Paper is more durable and disposable.
For our second attempt, we used crimp connectors. They were super effective!
Here's an old racer trick: mount your gauges so the needles are always pointing straight up when things are OK. That way it's easier to scan the gauges and see if something's amiss. If something's not pointing straight up, there's a problem.
The stud on one of those terminals snapped off the old coil when we tried to undo it, so we installed a new one. There's a problem with some of our new wiring, though, possibly related to our ABS delete. We're not getting any spark. Or maybe we just bought a bad coil. More troubleshooting awaits.
Here's a teaser: we have voltage! Proof, then, that our junkyard alternator was a good buy. But just in case, we plan to have a spare on race day.

But now the engine won’t start. There’s no spark. Crap.

In our last update, we mounted the alternator but hadn’t yet figured out how to wire it. A little Internet sleuthing yielded some useful pages on They have diagrams and photos of three generations of Ford alternators. We quickly identified our old one as a first-generation, and the junkyard-sourced replacement as a second-gen piece.

The old one had a bolt on the back to which we’d attached a beefy battery cable, but the new one used two comparatively skinny wires through a plastic connector. Our first attempt to mate those two didn’t work out so well.

So we did away with the oversized battery cable—this alternator only produces 75 amps anyway—and matched the wire sizes on the OEM connectors. Add a couple crimp connectors and voilà! Our alternator was nearly done. According to the wiring diagram on that website, the last thing to do was attach the green/red wire to a switched hot line—one that would be powered only when the ignition was on.

The coil’s hot lead sounds like a good solution here, until you snap off the stud on the coil trying to loosen the nut. That rendered our old coil useless, and our spare disappeared somewhere—perhaps into another project, perhaps into the boundless ether.

We came out alright, though: Our local parts store had one available for next to nothing. Victory was ours, just as soon as we fired up the engine and confirmed the voltage with our new in-dash volt gauge. That, too, was an upgrade, and crapcan rules have infinite allowances for driver information systems like gauges. Our old one had a failure light mounted under the hood, which wasn’t terribly useful when we were out on the track. We were excited to try out all our new accomplishments.

But the engine won’t start. There’s no spark. Crap.

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