Trying to get my electric choke dialed on my performer 750 in so my truck with start in 5 degree weather. Does the positive "hot wire" you attach cause the choke coil to come on or off???

The choke has an electric heater in it. When the wire goes hot, it heats up and the choke opens.

Botta-bing........Thanks Jim!

Make sure you wire the 'Hot' (key 'On') 12vdc through a dropping resistor to reduce the supply voltage to @7~8vdc.
If you wire the choke to full 12~14vdc it will probably burn out within a year or so.

Make sure you wire the 'Hot' (key 'On') 12vdc through a dropping resistor to reduce the supply voltage to @7~8vdc.
If you wire the choke to full 12~14vdc it will probably burn out within a year or so.

e-brock instructions say the opposite: they want a full 12 volts and caution you not to use a resistance wire. do you know something we don't?

I've never heard that, John. Mine is on full 12 volts, has been with no troubles for years. Always did bug me to have that lil heater running all the time.

I actually used the 12 volt supply the engine already had. I'm sure it will be fine. Thanks for the posts guys!

... do you know something we don't?

I know I hate replacing them every year or so on them lovely "Performer" carbs ...

I wire them through a GM standard line resistor. This gives them the full 12vdc for a few minutes to help them warm up, release the choke and then drops the line voltage to them to @8~9vdc to keep them off without burning them out.
I never wire them into the same resistor as the ignition as this pulls the voltage lower.
Never have any problems out this way, but I'm in sunny CA.
Holley, Carter and Rodchester all cautioned about this in their old catalogs - maybe they were more interested in customer satisfaction than selling parts ;)
Guess I'm helplessly Old's-cool :D

A resistor will give the heater some life I'm sure, at the expense of opening slightly slower. Mine is wired straight to 12 volts, but hasn't been running long enough to know if it'll burn out or not.

Most choke heaters now have 2 prongs - one for switched 12v (or whatever) and the other for ground. Don't depend on the carberator body to provide a ground - use both prongs.