here my wiring
everything is not connect....like a mess
1 green
2 black and purple
1 light blue
2 dark blue ( one is for temp or oil )
1 big purple ( for the starter )
1 big yellow
1 yellow
1 black and yellow
Here's a couple more diagrams that may be easier to read. If you still have points you'll need 2 wires to the coil, one with a resistor in the circuit.
It can be any one of those colors because this is a wirng diagram used over a period of years, not just 1970. I have white wires on 3 1970 Chevelles and the wire inside is a bright silver 16 gauge resistance wire.
There's a pretty easy way to check. Put a test light on one of the wires and then turn the key on. If it lights up it has 12 v. Then turn the key to the start position and see if it stays lit up. If it doesn't, then move to the next wire. The ignition will turn on power to the coil, but will interrupt power to other items when the key is turned to the "start" position.
Only if you leave your ignition on when the engine isn't running, and the points are in the perfect situation to try and fire. The reason Chevy went to an "acc." position on their key switch was to stop frying points. It brings on the system without giving power to the coil.
I've run a lot of 60's and 70's Chevys without a resistor and not burnt up points. Not running a resistor in my 327 powered gasser now, or my 427 powered Camaro, and no issues.
the 70 velle has a res. wire to coil..if running hie you have to bypass it..
as it drops volts to around 9v
I most times tap into the wire at the firewall bulkhead connector.. soldering in a splice.. leaving the old wire intact..
run the new wire and tape up the old one and wiretie it..
if your hei /etc fails you can drop the points dissy back in and untape the wire and down the road you go.. this is a plus with the drop in electric conversions.. as when they fail you just drop the points back in and go..
and murphy's law is because you have a back up. you'll never need it..
for some dumb reason GM repeated the same colors, but used different wire sizes for different things, I had Elect systems for a while when I was an engineer at Ford. We used to say the GM guys only had an 8 crayon box when they were a kid, and didn't know about more colors or wires with color stripes.
Depending on what was done before you got it...... One large cable to the battery, purple wire from the ing, yell or off white to the coil. The other wire you see on the dia is the braided wire that runs from the soleniod to the actual starter motor.
Earlier in the post someone wrote that the resistance wire is so that the points won't burn up if you left your key on etc...... maybe true but......... The resistance wire is so you won't burn up your coil.
If it's a stock floor shift set up, I would thing that there'd be a purple wire with white stripe to where the shifter would be if you had one. Also should be a purple wire there. Those are the ones I meant for you to jump, while turning the key to start.
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