Thursday, March 19, 2015

Getting Wired.

A while back, I referred to a conversation that had something to do with wiring and how much I enjoy it. I think part of why this assertion might have come across as completely bogus less than credible is that some of the people who are joining us here have actually seen what the wiring in the car looked like before I gracelessly yoinked it out of everything forward of the dashboard.
When I put the car together the first time, one of my goals was to minimize any irreversible modifications. For one thing, that meant that I'd avoid drilling new holes. For another, it meant that I'd use as much of the original car as I could. Mostly. The problem with this approach is that the fusebox didn't match the wiring diagram. Nor did some of the wires. So for a long time, I drove around with the original nasty looking - yet completely functional - fusebox, connected to similarly nasty looking original wiring:

Some of those wires aren't original, and the inline fuse holder certainly came along later. But this ugly thing met my Zero Permanent Impact priority.
I'd like to note that this car has never once blown a fuse since I've owned it. You can pooh-pooh me and my Reduce Reuse Recycle approach to motoring all you want, but my shit works. Aside from the fact that the car has been laid up for more than six months, I mean. In normal use on a street car, I mean. In a completely mundane non extreme environment where it's not expected to meet any standard for excellence, I mean. Where there aren't any safety inspectors for old cars, I mean. Dead reliable.
Once all the wires were pulled to the cabin side of the firewall, everything made perfect sense:

That snaggle of wires had to stay like that for a few weeks, as there were some fundamental changes to the wiring layout pending, and I didn't want to (further) upset anything that was in the car until I had a better idea of which wires would be removed, which would be rerouted, which would be replaced, where new ones would be added, etc etc.
While I was panicking mapping this all out in my mind, I took decisive action. Like as though I might change my mind on the whole deal or something. Anyway, I drilled a hole in the cowl for the required battery disconnect switch:

I have this vision that I'll be sitting at a red light and some smartypants pedestrian will reach over and shut the car off before the light turns green. I'd totally do that to someone if I had the chance.

The battery disconnect has to fully shut off all the electricity to the car, so if you have an alternator, you'll want to ensure that you get a switch that prevents the alternator from frying itself if you throw the switch while the engine is running. If the power that the alternator is producing suddenly has nowhere to go, it can self destruct. So I'm told.

Adding this switch changes the routing of the Big Power Wire that used to lead from the alternator to the ammeter and then on to the starter. We could have routed the alternator through the ammeter and then to the cutoff switch (thus retaining a functional ammeter), but decided to bypass the ammeter altogether. Fewer terminals and connections for this critical wire means fewer chances of voltage drops or faulty connections. The car has an amp light and a voltmeter. Those should be enough to monitor the relative health of the charging system as a whole. We tossed the 10 gauge stuff and replaced it with 8 gauge also, as Automotive Electrical Smart People say that 10 gauge is only good for up to 30 amps. We have more than 30 amps.

One thing about electric stuff in old cars: the electricity generally goes from the source (the battery, or the generator or alternator) side of things, through the switch, and on to the load (lights, fan, wipers, etc). This is alright (sort of), but if you make the electrical pathways shorter and use larger gauge wiring, you reduce the possibility of a voltage drop (actually, a few possibilities for voltage drops) between the source and the load. It might seem like a lot of effort for a minor improvement, but it's really worthwhile - the electrical load on the switch(es) is greatly reduced (this is a good thing) and the electricity faces a lot less resistance on its way to the load side of things. If you're dealing with lights, know that a 10% drop in voltage to the bulbs themselves reduces light output by about a third. You want full voltage at the bulbs.

Also, if you're going to do something silly and run a pair of 80/100 watt H4 bulbs that come in a box that says "not for use on public roads," you may well overwhelm the original wiring in the car. Melting the insulation off the wires is only cool if later that evening you can talk about how it didn't burn your car to the ground.

We don't want this. Image credit:
The ol' Volvo is now fitted with a second fusebox, a junction block from a 240 (that's the black rectangle on the left), a reverse relay from a 122 (the round canister next to the black rectangle) and five relays taken from various wrecking yard 240s:

The use of old relays instead of fancy new ones is certainly questionable. Part of the problem is that when I recently ordered some "Hella 40 amp relays" online, the things that arrived weren't Hella branded at all and weren't manufactured in any of the countries I'd associate with Hella. So until I find some suitable, high quality relays to use, I'm going with the "Bosch from back in the old days when their quality control was top notch" for now.

Because I like using old things, I came very close to installing a second fusebox taken from another PV series Volvo. But that seemed a little overboard with the Vintage Factor and lacking in the High Reliability Factor. Form follows function. Or something.

Once I'm not completely behind on getting the car on the road, I'll return to the relays and fit the car with whatever Daniel Stern recommends. He's probably the smartest automotive lighting specialist in North America. Check him out here:

The ignition stuff comes next. Though I'm generally happy with points and condsensors (and I sure do like that they're easily replaced alongside the road on dark and stormy nights), we wanted something more macho for this application. This led to a few conversations and more researching, and that led to a Crane XR3000 (a lot like the more common Crane XR700 but more expensive) and a PS91 'Fireball' coil. If it's called 'Fireball' it probably kicks serious rump. It looks more like something the Terminator uses than it does an ignition coil.

Even with the heater removed from the firewall, there's not a lot of room for things like high zoot coils and ignition boxes. We thought about putting the coil on the pedal box, but chose to keep it away from the hydraulics, just so that ' various things that might need servicing' aren't all cramped together. So the coil went where the battery used to be:

I'm not completely happy with this layout from an aesthetic perspective, but it meets the 'functional and easily serviced' criteria. And there's room leftover in the battery box for other things. Not sure what other things, exactly...

One way to encourage promote enhance reliability is to add redundancy. The 5 relays shown above are one example - we're only going to use 3 of them, and the other two are standing by so that if one relay fails, we just move two wires over to one of the unused ones.

Along this line of thinking, and because we want as many of the controls and monitors accessible by both the driver and the codriver, most of the controls for the electrics have been moved to a panel located in the middle of the car.

The foot switch for the hi/lo beam selector has been replaced by a DPST toggle on the left, next to that an SPST toggle for the fog light. Next to that is a switch that activates the reverse light (these cars didn't have reverse lights, so ours has a 55w Cibie Tango foglight on the back of the car). The 'normal' reverse light switch on the transmission is also in place but we may find a reason to light up everything behind the car at a time that we don't actually want to be driving backward. Tailgaters beware.

All LCP cars have to have Hazard Lights, so we added a switch for those. If you look online, you'll find fancy kits to retrofit 4 way flashers onto an old car that didn't come with them. The kits have plenty of wires with diodes and a relay and they cost about $60. Instead of that, we bought a flasher relay for $4 at the local auto parts store and wired it between 12v+, through the switch, then on to the wires that lead to the car's turn signals. Simple. Works nicely. If you do this, use a DPST switch so that you can run separate wires to the left and right lights, otherwise you'll create a feedback loop and all 4 lights will flash when you activate the turn signals.

Next to that is will be a fan override. The electric cooling fan has its own temp sensor and an adjustable switch, but we want to be able to run the fan if that system should fail. So there'll be a switch for that.

Finally there's a switch for a siren. We're required to have loud horns (and we do) but we're adding a siren so that we can make a whole lot of noise if needed (and we may put an alarm in the car, strange as that sounds). We're hoping that during the race we might pass someone, and to do that, you have to announce your presence. The codriver gets his own horn button also, though that's not yet in place.

The indicator lights on top of the dash are just so we know when different things are working (or not). The larger lamps on the left are oil pressure and amp warning lights (444s didn't come with those), and the smaller ones are just monitors for the fog light, reverse light, and fan. We want to know when the fan turns on and off, and we don't want to drive around with fog or reverse lights on when we don't need them.
The fusebox is tidier than before also, and to keep things easy to service, is now labeled both with load items and wire colors:
I don't have any of the little short 25amp fuses around anymore, but after adding a second fusebox, really don't need more than these 4. The 4 contacts on the upper right are connected, so though it doesn't look like the white fuse is getting any power, it actually is. Red = B+ direct, Green = switched 12v.

The very good news is this: we hooked up the battery and nothing bad happened. Instead, every single thing that has to do with the new wiring stuff works exactly as intended. Super cool.

And that's actually where the car is at this point. The only remaining tasks before we can test drive the car are to get the fan wired, bleed the brakes, and connect up the clutch hydraulic lines. Then there's a whole long list of things to do after it runs and drives. We'll get to that when the time comes.

Cheers --

No comments:

Post a Comment