[Cliff R]

Yoiu do not need to help the engine start with additional throttle.

Set the fast idle speed to do that for you.

Usually one or two pushes on the throttle is enough to set the choke flap, raise the cam to the highest position and put enough fuel into the engine so it fires up just like fuel injection.

The choke pull-offs job is to open the choke flap to the ideal angle so it's neither rich or lean while on the highest step of the fast idle cam. I'll add here that IF you have replaced your plastic choke pull-off in the last 15 years or so with one of those cheap POS while ones it is NOT going to work well. When they suppliers went off-shore for those parts the Chinaman put a spring inside them that requires over 14" vacuum to apply the unit. Factory specs are 5-6". Those pull-offs also open INSTANTLY so you get screwed twice and they do NOT dampen the secondaries going quickly to full thorttle. I've been modifying those pull-offs with the correct spring and adding a tiny restriction to the inlet for many years now so they work like they are supposed to:

https://cliffshighperformance.com/pr...pull-off-67-70

The fast idle speed screw must also be adjusted for optimum RPM on initial starts. After about 10-15 seconds tap the throttle once and the fast idle cam will drop to the next step and the engine RPM's will slow down, but it should continue to run just fine.

Some fast idle cams have more steps than others so there may be one or two more drops in engine RPM's if the push lightly on the throttle during the warm up process. Once the choke coil is hot enough it allows the fast idle cam to drop out of the way and the throttle speed is then controlled by the idle speed screw.

Early divorced chokes are somewhat of a PITA to get set up right as you have to bend a few things in the mix. Pontiac Q-jets 73-74 have an adjustable hot-air choke but you still have to bend parts to acheive the ideal open angle of the choke flap at start-up.

1975 and later hot air and electric choke carbs are adjusted by turning the choke dial for how long the choke stays on and a phillips head screw on the pull-off for the angle of the choke flap.

Factory choke coils, both divorced and hot-air were very well made and unless they get exposed to the elements and rusty will usually last just about forever.

The biggest problem I see here with factory chokes are folks blocking off heat crossovers or going to heads that don't have them. At that point an electric choke upgrade is going to be required, unless you want to put a hole thru the firewall for a cable and mount it under the dash.......