Designed and calibrated for small cubic-inch engines such as 305 c.i.d and smaller Chevrolet; 302 c.i.d. and smaller Ford and dual-quad applications such as our new RPM Dual-Quad Air-Gap, Edelbrock C-26, F-28 and Street Tunnel Ram. For single carb applications, match with an Edelbrock Performer or Performer EPS manifold or other brands of similar design. Includes both timed and full vacuum ports for ignition advance. Edelbrock Thunder Series AVS Carb 1803 500 CFM - Square Flange - Electric Choke - Dual -Quad Carb - w/o EGR - Includes Primary Jet-.086/Secondary Jet-.077/Metering Rd - DualPlane Intake - Street/Hi Performance UsageNew Qwik-Tune Adjustable Secondary Air ValveOptional Single Or Dual Fuel InletDistinctive Black Accented HardwareNo Gaskets Below Fuel Level to Prevent LeakageMetering Rod/Step Up Springs Can Be Changed EasilyGM/AMC-Style Throttle LinkageExclusive 12 Month Complete Satisfaction WarrantyPit Stop USAoffers Edelbrock Thunder Series AVS Carb 1803 at low everyday prices. Be sure to check out all of the products from Edelbrock including Edelbrock Fuel System and Intake Parts and Accessories, Edelbrock Carburetors, Edelbrock Gasoline Carburetors, Edelbrock Carburetors, Edelbrock Thunder Series AVS Carburetors.