My choke is coming open totally before the car even gets off the 100 degree mark on my temp guage. I know this cant be right. Also the car is spittering and sputtering...feels almost like backfiring. But I dont think it is. Timing is at 10 degrees base without advance and around 13 with the advance hooked up...9.6:1 on 93 octane only and 6 PSI fuel pressure. Car is running a tad rich so it isnt lean (little bit of black smoke)

Im pretty sure my choke is causing this. earlier in the winter it would start and run fine with the electric choke. didnt do what its doing now. also the other day my choke got stuck wide open and i had to sit and feather the gas for awhile to get it to stay running

whats your alls diagnosis here?

 

I'm not positive about the choke setup on the 670, but have you tried to retension the choke spring? Also, what power source are you using to supply the choke? Early factory electric chokes used an oil pressure switch to operate the choke to prevent early opening.

Does the carb have a vacuum choke pull-off?

 

Dont think the choke is vac controlled in any way.

I have a wire going into my fuse box controling both my fuel pump and my electric choke. This wire is in with a 25amp fuse and spliced into my fuel pump relay and then my choke.

I had to wire the fuel pump to stay on at all times since I switched from TBI. I might go ahead and run a different wire to the choke and see what happens. It is definetly opening way to soon.

BTW the 670 has the same electric choke and the regular holley carbs I do believe.

 

I'd suggest setting the choke spring a notch or two tighter.

 

The metal part of the choke thermostat housing does indeed have a vacuum pull-off piston contained within it. I've never tried to adjust it, not even sure if it is possible (because I haven't had to worry about it).