24 hours of LeMons Build Blog

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We made it through tech and BS inspection just quickly enough to get into the last practice session on Friday. Mat was the only driver with any experience at Infineon (other than Tommy, who graciously refused to go first) so we decided he should be the first to take the Z out. Mat bravely climbed into a car that hadn’t been above 40mph since having been completely rebuilt from the ground up and took it around the track for 3 uneventful laps. Bryan followed, then George, then I took the car out and got the checkered flag that ended the session before Tommy could get a chance.  The car didn’t miss a beat. It works!

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I realized pretty quickly how little I remembered of Infineon. There’s nothing quite as terrifying as wondering “what’s the next turn?” in an open passing practice session.  Mat and Tommy had Infineon experience and George and Bryan had studied with hundreds of laps in Gran Turismo 4, but I’d been too busy building the car. Fortunately, George brought his playstation so I did 50 laps of homework back in the hotel Friday night.

We queued up for tech inspection and passed without any major snags

Then arrived at BS inspection. We presented our box of bribe beer, holy homebrew and documentation to the judges

Who had no interest in our documentation whatsoever and reacted to our adjustable Tokico Illuminas like a bulls to a red flag. They conferred, weighing our suspension against our ample bribes:

And decided to give us 3 BS laps and our bribed stencil. Good enough!

The ever-growing bribe table (which they actually divide up amongst the corner workers)

Mat and I towed the Z up to the Pick-n-Pull in Newark Friday morning, set on scrounging a spare distributor from another 300ZX like ours. The yard’s website claimed they had 5 donors in inventory but when we showed up we only found 2 that had been picked clean. Desperate, we ended up plucking two complete distributors from late 80s Maximas that shared the same VG30 engine with our car.

I installed the first distributor while standing on the trailer in the Pick-n-Pull parking lot and got in the car to start it. I was waiting for the fuel pump to prime, about to bump the starter when Mat yelled “stop!” - I’d left a fuel line loose in my hurry to get the distributor in and was flooding the engine bay with gasoline. Oops. Mat washed the engine down with (holy?) water and we gave it another shot.

The Z started up on the first try. We packed up and got out of there around 10AM Friday morning.

We were packed up and ready to load the car on the trailer when the Z decided it didn’t want to start anymore. It was about 2pm on the Thursday before race weekend. We checked the basics: no spark. We ran out to the local junkyard and grabbed spare ignition parts, but swapping the ignition coil and power transistor didn’t help. Frustrated and realizing our race weekend plans were rapidly falling apart, I borrowed a scope from work and dove into the ignition system with Mat to figure out what was wrong.

Around 10PM we determined the problem was the crank angle sensor. The crank angle sensor has two outputs: one that pulses every 120 degrees of rotation with various widths so the computer can figure out where the engine’s absolute rotation, and another that pulses every degree for fine timing. More details here. The 1 degree output was dead. We checked and double checked every way we could think of then came up with Plan B: leave for the race Friday morning and swing by a Junkyard on the way to get a spare distributor.

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Been too busy getting the car ready to post any updates. We’ve made lots of progress and are pretty much ready, which is good given the race is Saturday!

Simple fan controller for the new electric fans

Seat, harness, fire extinguisher and a few gauges installed

Electrical kill switch installed

Mat cutting vents into the hood. Will the artwork survive?

Yes! Quite well, actually.

Mat is a machine. He attacked the wiring harness in the cabin, starting with this:

Removed this mess of unnecessary wire from various accessories

Leaving this