Cadillac 60 Series 1963 Shop Manual page 270

FUEL & EXHAUST
10-35
ROCHESTER 4GC SPECIFICATIONS
Throttle Bore
Primary 1-7/16"
Secondary 1-11/16"
Main Venturi
Primary 1-1/8"
Secondary 1-15/32"
Small Venturi
Primary 1/4"
Secondary 1/4"
Low Speed Metering
Primary Side
Idle Tubes 045"
Channel Restriction 060"
Hi-Speed Bleed 050"
Top Bleed, Over Idle Tube 052"
Secondary Side
Idle Tubes 030"
Channel Restriction None
Hi Speed Bleed (2) 028"
Lower Idle Air Bleed 060"
Top Bleed, Over Idle Tube 052"
Main Metering Jets
Primary 056"
Secondary 075"
Power Valve Restriction 050"
Choke Setting 1 Notch Rich
Float Level
Primary (Gasket to Float Top) . . . 15/64"
Secondary (Gasket to Float
Heel Bottom) 1-3/8"
Primary (Power Piston Up) 1-3/32"
Secondary (Gasket to Dimple) 3/8"
Float Drop Gasket to Dimple
Primary (Power Piston Down) . . . 1-1/2"
Secondary 1-5/16"
Accelerator Pump
Capacity - 10 Strokes 9-12 cc
Jets 026"
Idle By-Pass
Primary Throttle Blades 101"
Idle Mixture Screws
(Turns Open) 1-1/2 to 2-1/2
Idle By-Pass Air Screw
(Turns Open) 1-1/2 to 2
Idle Speed
Standard 480 RPM in "DR"
Air Conditioned with . . 480 RPM in "DR"
A/C on 900 RPM in "N"
with Idle Speed-Up "ON"