If you block it the choke will overheat. All it does is let some air flow past the choke housing. That's why it has the bronze filter on it, to keep dirt out.
If you block it the choke will overheat. All it does is let some air flow past the choke housing. That's why it has the bronze filter on it, to keep dirt out.
Thanks, KitCarlson. I needed to know the name of it: "choke pull-off piston". Holley failed to include the part in the instructions or exploded view. I theorize that it's only one the 870 Street Avengers.I don't know about that Holley, but some carbs have a choke pull-off piston there, operated by vacuum. When the car starts the vacuum tilts open the choke a small amount.
I cannot see a vacuum port. Can you get a better picture? If it comes straight out of the base plate, it probably should be plugged. The large nut looking fitting behind the choke is the inlet for the vacuum piston.....which is clearly visible as the round cylinder on the front of the choke housing sticking down about 5 o'clock.