cold-start choke setting

[plym_46]

what you are describing is probable the high idle step up cam and adjusting screw.  This controls idle speed when the choke is engaged, providing a faster idle speed to allow for faster warm up and smoother running on an richened fuel mixture.  This should only come into play when the choke is engaged and will return idle speed to normal when the chole pull of returns to normal when proper running temp is reached and the chole opens.  You need to check to see if the cholke is closing when the engine is cold and opening fully when it is at operating temp.  This can be checked with the air cleaner off.  The choke is set by depressing the gas pedal to to the floor.  This should also allow the linkage from the choke to the high idle cam to move the cam into place.  Assuming all is correct the idle speed should be set with the screw to about 600 RPM with the engine hot and the choke off.  the two mixture screws at the base of the carburetor are for adjusting the idle air mix, and do not have any effect on engine operation once the throttle butterflies open.

[dickf1976]

I am restoring a '56 Belvedere w/ a 277 V-8 and 2-barrel carburetor. If the engine is not warm, it takes too many cranks to start -- probably because I changed the cold-start set screw setting, thinking it controlled the idle speed. (The set screw pushes against a cam, and is the screw closest to the driver's side of the engine compartment) Q - How do I set the set screw for cold start. Thanks. Dick Friedman -