I'm having cold and hot start problems w/ my 350.It has a mild cam,edelbrock performer intake and carb,Gear drive.Headers.The motor stumbles, cuts out and after a few more tries it will start but only if I blip the throttle just a bit for half a minute.There is not a heat riser from the headers into the intake.Manual choke.It does this same thing when the motor is cold and when its hot on a restart
Sounds like your idle mixture might be too lean. But the cold start thing sounds normal-what CFM carb? Mechanical or elctric fuel pump? Sitting how long when this happens?
and what ignition? If you have the stock points, you need the "Chevy start bypass" wire to give a hotter spark during cranking....
Cold start is when its been sitting a few days.I believe its the 600 cfm carb.Electric fuel pump at 9psi
When its cold I give the fuel pump about 20 sec to get fuel to the carb.Close choke all the way.Push gas pedal in once and attempt to start.If it seems like its close to actually starting I will then close choke half way....is this the correct way?
All carbureted engines have their own combination when it comes to starting them. In cold weather you well normally pull the choke all the way out (closing the choke butterfly) Pump the accelerator once and hold it down about half way, crank on the starter and if it starts push the choke in about half way or to a point where the engine idles smooth. Sometimes it may take a pump or two on the accelerator pedal and sometimes not. In warm weather or with a warm or hot engine maybe no choke is needed just a pump or two on the pedal. Just have to get a feel for what yours likes. No EFI to do the thinking here.