Warm the engine to operating temperature
Set ignition timing and valve lash first
Check for vacuum leaks
Verify fuel level in the float bowls
Clean or replace air filters
Inspect spark plugs, wires, cap, and rotor
Start with idle mixture screws at a baseline setting
Set idle speed to specification
Adjust each idle mixture screw for highest smooth idle
Recheck idle speed after mixture adjustments
Synchronize multiple carburetors if equipped
Adjust throttle linkage so all carbs open evenly
Tune the accelerator pump if there is hesitation on throttle tip-in
Adjust main jets only if needed after idle and midrange are correct
Test drive through idle, cruise, and wide-open throttle
Read spark plugs and check for lean or rich signs
Make small changes one step at a time
Recheck after each change until the engine runs cleanly