Edelbrock AVS2 1905 650 cfm Square-Flange Carburetor Satin finish, annular boosters for improved throttle response

The Edelbrock AVS2 Series 1905 is a 650 cfm, 4-barrel satin-finish carburetor with annular-flow primary boosters and a manual choke engineered for improved off-idle response and smooth cruising behavior.

This AVS2 1905 model is the next-generation Edelbrock carburetor designed to upgrade induction on small-block and big-block V8 engines. It uses annular-flow primary boosters with eight equally spaced orifices per booster to improve fuel atomization and minimize flat spots when transitioning from idle to throttle. Finished in satin, the unit includes both timed and full vacuum ports for ignition advance and comes pre-jetted and rod-equipped for a wide range of naturally aspirated applications.

How does the AVS2 1905 improve acceleration and throttle response?

The annular booster design delivers finer fuel atomization during the transition from idle to main circuits, which reduces flat spots and yields crisper throttle response. Calibration changes in the AVS2 advance off-idle and part-throttle performance compared with conventional boosters.

• Annular primary boosters with eight orifices per booster for better fuel distribution
• Factory metering jets: Primary .101 / Secondary .098 for balanced flow
• Metering rods .070 x .037 and orange step-up spring optimized for ~5" Hg
• Timed and full vacuum ports for flexible ignition advance setups

What engines and intake setups are best matched to this 650 cfm carburetor?

With a 650 cfm rating and a square-flange mounting, the 1905 is suited to many street and mild-performance small-block and big-block engines. It works well on both single-plane and dual-plane intake manifolds where a mid-range powerband and street-friendly drivability are priorities.

• Ideal for naturally aspirated small- and big-block V8s where 650 cfm is appropriate
• Compatible with dual- and single-plane manifolds for street and light-performance use
• Square flange interface fits common aftermarket intake manifolds
• Pairs especially well with Edelbrock intakes for simplified tuning

What tuning and installation details should I know before buying?

The AVS2 ships with factory jets and metering rods that suit many stock and mildly modified engines, but some vehicles may require jet or rod changes for optimal mixture. Use Edelbrock carb studs #8008 or #8024 if your manifold needs stud conversion.

• Factory jetting: Primary .101 / Secondary .098; factory metering rods included
• Step-up spring (orange) tuned for approximately 5" Hg vacuum conditions
• Manual choke configuration requires linkage and heat source consideration
• Carb studs #8008 or #8024 recommended if manifold stud pattern differs

How does the manual choke affect cold starts and drivability?

A manual choke gives you direct control over enrichment during cold starts and warm-up, which is useful for classic cars and custom installations where automatic systems are not desired. Proper choke use reduces over-rich conditions once the engine reaches operating temperature.

• Manual choke lets the operator control cold-start enrichment precisely
• Reduces unnecessary enrishment after warm-up when used correctly
• Simple mechanical design compatible with older or restored vehicles
• Requires driver attention during startup compared with electric chokes

Who is this for: The Edelbrock AVS2 1905 650 cfm carburetor is aimed at enthusiasts restoring, upgrading, or tuning street-driven V8s who want improved off-idle behavior, dependable midrange performance, and a satin aesthetic. It’s a strong choice for owners of classic cars, resto-mods, and street/strip machines that run naturally aspirated setups and benefit from manual choke control and straightforward mechanical tuning.

• Features: Satin Finish, 4 Barrel, Annular Booster Type, Manual Choke, 650 cfm