build diary

February 16, 2004:
I started on the wiring last night.
It turns out that my donor car was cannibalized for many useful connectors before I got it. Most of the specialised parts I wanted are AWOL. Sigh. Still, it does have a lot of what I need. I've taken the harness apart so that I can make as neat a harness as possible and to ease the conversion over to the 1.8 computer.

The GRM car does have the same diff mounts that mine does, but they might not have the bolts fully tight. They also used smaller diameter bolts than I did.
entry 132

Wiring time!
I'm starting by unwrapping the Miata harness. I'm only going to use what I need.
entry 133
Looks like mice had a little fun with my wiring.
Oh goody.
entry 134

February 18, 2004:
I've been poring over wiring diagrams and trying to decide exactly what I want to do.
The picture is becoming clearer, but there are still some grey areas. It certainly would be cheaper and easier to simply run the stock setup from the car but that wouldn't do some of the things I want to do. My 1.8 coils did arrive today so I have everything needed...
entry 135

February 22, 2004:
Wiring work has begun in earnest.
I've spent a lot of time thinking about the various buttons and lights I want to use because it's fun. I've even found an extra ignition switch and key so I could use that if I wanted. But before I do that, I have some work to do on the harness. I'll weigh the leftover wires when I'm done, but based on what I saw on our Track Dog race car there is 20 lbs of wire waiting to be removed out of the harness. It's quite entertaining once you get started but it takes a bit of nerve. I'm trying to retain the stock 1995 wiring colours whenever possible but since my donor was a 1990 it's sometimes a little tricky. I've got a notebook full of notes as well as a factory manual and wiring diagrams for both 1990 and 1995. I've found some interesting things - including what appears to be the ability for a US-model car to honk the horn by jumping the right pins in the diagnostic connector. What?

On a different note, I had the scuttle and nose in place. Turns out there is minimal (ie, no) clearance between the engine and the hood. This might be fun to work out. I'll also have to cut out the bottom of the scuttle for my legs a little, but a lower seat would avoid this.
entry 136

This is a mounting point for the shoulder harnesses.
But it's on the back of the bar on the GRM frame while it's on the bottom of mine. Hmm.
entry 137
Hmm.
There's about 3" from the top of the head to the hood. Great. But the valve cover is just a little taller at the oil filler. I might have to move the fill hole like we did on the FM Track Dog race car.
entry 138
In order to the 1.8 coils on the 1.6 engine, I can mount them in the 1.6 bracket with a bit of modification.
That will be a nice clean setup.
entry 139
More wiring.
I draped the harness over the car to help with physical layout. I know the wiring of a Miata well but not when it's curled up on a workbench!
entry 140
The Link ECU doesn't use every pin in the wiring harness - you can see how some of the pins at the top are not connected on the single-layer circuit board.
Those wires come out!
entry 141
Missing connectors? Turns out the pins are the perfect size to take ECU connectors.
A bit of heat shrink and it's ready to go.
entry 142
There's a lot of weight to be saved by thinning out the wiring harness.
This is the wiring to make the headlights pop up, not including relays and motors!
entry 143
A local parts store find - front turn indicators for $2.99 each.
Plastic and super-light too.
entry 144

February 23, 2004:
Well, the ECU wiring is almost done.
It's taking a long time because I am tracing each wire before removing it from the harness. This helps me understand how the original car was wired and also (hopefully) prevents mysterious problems down the road. This is not something you can do on a two-day build but it will be worth it! I'm getting closer from a conceptual standpoint of where everything will go and how I'll wire the car using only half as many fuseboxes as before. I do have some questions about Colorado law, though - do I need running lights or will headlights be okay? Can I register the car without a windshield, and therefore no wipers or squirters? Time to find someone who has been through this.
entry 145

The steering column cutout wasn't in quite the correct place.
The shape of the firewall isn't right either. CMC might have a little tweaking to do on their aluminum panel cutting.
entry 146
A stock Miata battery will not fit in the battery tray.
Granted, the OEM Panasonics are rare these days (this one is 14 years old and still works) but the kit is designed for a Miata donor.
entry 147
A Mazda replacement battery or the popular Wiseco batteries will both fit.
entry 148
The wiring saga continues.
Here is some of the wiring that was removed. Some will be put back in as I'm starting with ECU-related wiring only.
entry 149
There is lots of room to hide wiring and relays on the back of the firewall.
They won't be easily accessible when I'm done, but I'm not expecting a high failure rate. The fusebox is a bit more of a challenge. As you can see, the wiring loom has been heavily simplified.
entry 150
The ECU and the related MAP sensor are mounted to the firewall in the engine bay so that they are easily to reach.
A bit of work will make the ECU case more weather tight - but it's not as if the car will be waterproof anywhere else!
entry 151
The next challenge - fitting some of the stock instruments.
I am not a fan of simply sticking the gauge pod on the dash but these instruments don't really stand alone. I've got an idea...
entry 152
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