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Wiring fun!

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Morris

Morris

Yoda
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I am planning to expand the "great wiring harness cleanup of 2008" into 2009. The main objective of the plan is to run everything switched on the car with relays. As part of the plan, I would like to run a single power wire to fuse block at the front of the car. Said wire will carry current for my electric fan, head lamps and horn.

Would anyone dare to venture a guess on what gauge that power wire should be? I have read conflicting info on the max allowable load for 10 gauge wiring. One source says it can safely carry 55 amps, while another says 30. Can anyone give me an idea of what kind of current the headlamps draw at high beam?

Also, do as anyone have an old wiring harness from a late model Midget he would like to get rid of?
 
Thanks Bud.

According to that chart, for the 3'-4' run I am planning to make with the wire, 10 gauge is more than adequate. In fact, at that length, 10 gauge can handle double the max output of my alternator. :smile:
 
#12 is probably fine for just about anything you'll encounter in an LBC, with the possible exception of wiring directly from the battery or the alternator. The place to be concerned is connections, not so much the wire itself. Make sure all connections are good, tight, and solid. I use a lot of push-on terminals, but I solder the wire to them.
 
My plan IS to wire directly from the battery. Do you think #10 will be adequate?
 
Classic Motorsports says: (about driving lights)

H3 bulbs draw 55 watts. since amps = watts/volts, each lamp draws 4.58 amps (55/12) therefore in total 10 amps.

you should be able to do the math for what you have.

I used 40 amp relays because that was what they had and 14 guage wire direct from the solenoid - one wire for low beams, one for high (in case one burned out) and I fused them also.

FWIW, I put relays on the headlights, driving light and horn (4 total). For driving light and horn, I used the existing wire harness purple feed to the horn (as did Classic Motorsports) For the headlight, I did the solenoid direct feed.

I think anything other than those (and maybe a stereo) is overkill for relays. Mostly because the rest just doesn't draw that much current, and partly because you've relieved the whole electrical system of a lot or current by taking the headlights out of the wiring equation. I would put relays on those things, put a fuse on the dashboard lights, get a GM alternator and drive.
 
texas_bugeye said:
Are you putting a fuseable link between the battery and the fuse box?
Click to expand...

haven't - how would that work? (ie, where would you put it/ amperage etc)
 
This is a timely thread, I was mucking about in the engine bay admiring the POs wiring handiwork... NOT. He seems to have bypassed the original fuse box (all two of them) in favor of one or two inline fuses hidden wherever, the original harness is there and most of it is in use although the jacket is 90% gone. In the box of parts is a brand new harness. I probably should strip out everything and rewire it all.....I guess......although there's just enough "custom" stuff to make me think (dual blinker indicators, some other solenoid, push button starter) probably not insurmountable though.
 
Morris said:
My plan IS to wire directly from the battery. Do you think #10 will be adequate?
Click to expand...

It's the current in the circuit that matters, not where it's wired from. Everything eventually is wired to the battery, when you think about it. Make sure it's fused; that's the main thing.
 
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