electrical system requirements

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70MTroadster

electrical system requirements

Post by 70MTroadster »

Can someone break down the amp requirements for each of our Roadster's systems? Headlights, heater set on high fan, running and instrument lights, wipers, brake lights, EI, etc. I don't know if I've seen it broken down like this before.

I have the 60 amp GM upgrade on my 70 and I would just like to know how much "extra" I have for powering 2 ea 100 watt driving lights and perhaps some Hella H4 100/80 headlights.

Thanks in advance for any help.

Scott
TR

Post by TR »

I'm pretty sure this has been discussed before, I think on this forum. You may search for more info...

Amp draw for new items is simple to calculate:

Power (Watts) = Current (Amps) * Voltage (Volts)

Everything on the car runs at ~12V, so a 100 Watt bulb draws 100/12 or 8.3 Amps.

The original Amp gauge is rated for 30 Amps, so you know the original car pulled much less than that. Add your new item on top of that...

Of course, don't run all the new gizmos through the original wiring and gauge, use relays and fuse the original gauge to protect the car from fire. You'll also want to run new wiring to the headlights in addition to modernizing the relay. TR
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