{"product_id":"generic-1904r-rochester-quadrajet-4mv-4-barrel-carburetor-for-chevy-305-350-750-cfm-vacuum-secondary-with-electric-choke","title":"Generic 1904R Rochester Quadrajet 4MV 4-Barrel Carburetor for Chevy 305\/350 750 CFM Vacuum Secondary with Electric Choke","description":"\u003cp\u003e\u003cstrong\u003eThe 1904R Rochester Quadrajet 4MV is a direct-fit, 4-barrel replacement carburetor with an electric choke and 750 CFM vacuum secondary engineered for 1980–1989 Chevy 305 and 350 engines.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis replacement carburetor restores drivability for older GM small-block V8s by matching the original Quadrajet 4MV footprint while refreshing worn fuel metering with updated components. It’s built for mechanics and restorers who need a practical, bolt-in part that supports EGR systems and simplifies cold starts with an electric choke. The 1904R is offered as a complete assembly with gaskets, ready to swap into vehicles that originally used Rochester Quadrajets, without aftermarket tuning complexity.\u003c\/p\u003e\n\n\u003ch3\u003eWill this 1904R carburetor fit my Chevy 305 or 350 from the 1980s?\u003c\/h3\u003e\n\n\u003cp\u003eYes — the 1904R is designed as a direct replacement for 1904R\/1906R Quadrajet 4MV units and fits most 1980–1989 Chevy\/GM 305 and 350 cubic-inch engines. It retains the factory mounting pattern and EGR compatibility, so installation requires no manifold modification on compatible engines.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eExact bolt pattern and throttle linkage location for 4MV manifolds\u003c\/li\u003e\n  \u003cli\u003eEGR port compatible with original emission plumbing\u003c\/li\u003e\n  \u003cli\u003eElectric choke wiring attaches to existing harness for cold starts\u003c\/li\u003e\n  \u003cli\u003eIntended for standard passenger cars and light trucks using stock Quadrajet setups\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does the 750 CFM vacuum secondary help everyday driving?\u003c\/h3\u003e\n\n\u003cp\u003eThe 750 CFM vacuum secondary design provides a balance between fuel economy at cruise and available airflow under load. Vacuum-operated secondaries open progressively with engine demand, producing smoother throttle transitions and reducing the abruptness that some mechanical-secondary carbs can produce.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eVacuum secondaries delay full airflow until needed, improving part-throttle economy\u003c\/li\u003e\n  \u003cli\u003e750 CFM rating supplies sufficient air for 305–350 engines without over-carbureting\u003c\/li\u003e\n  \u003cli\u003eSmoother acceleration for street-driven vehicles and daily use\u003c\/li\u003e\n  \u003cli\u003eLess tuning sensitivity than larger, high-CFM racing carburetors\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat features support reliable starting and long-term durability?\u003c\/h3\u003e\n\n\u003cp\u003eThis unit includes an electric choke that helps achieve consistent cold starts and a stable idle until the engine warms. Components are manufactured from corrosion-resistant materials and undergo durability checks to reduce fuel leaks and wear over time, making the carburetor a dependable replacement for aging Quadrajets.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eElectric choke for predictable cold-weather startups and quicker warm-up\u003c\/li\u003e\n  \u003cli\u003eSealed gaskets included to prevent vacuum leaks on installation\u003c\/li\u003e\n  \u003cli\u003eCorrosion-resistant metal finishes to extend service life\u003c\/li\u003e\n  \u003cli\u003eFactory-style design minimizes need for aftermarket adapters or modifications\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat comes in the box and what will I need to install it?\u003c\/h3\u003e\n\n\u003cp\u003eThe package contains the assembled 1904R carburetor plus gaskets and basic mounting hardware, giving you the core parts for a direct swap. No printed instructions are included, so basic carburetor installation knowledge, a torque wrench, and access to a service manual or wiring diagram are recommended for a safe, correct installation.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eIncluded: carburetor assembly, intake gaskets, mounting studs\/bolts where applicable\u003c\/li\u003e\n  \u003cli\u003eNot included: step-by-step instructions or vehicle-specific tuning info\u003c\/li\u003e\n  \u003cli\u003eRecommended tools: hand tools, torque wrench, vacuum gauge for final adjustments\u003c\/li\u003e\n  \u003cli\u003eIdeal follow-up: check for proper fuel pressure and adjust idle mixture after install\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: The 1904R Rochester Quadrajet 4MV is intended for classic Chevy owners, restorers, and mechanics maintaining 1980–1989 305 or 350 small-blocks who want a reliable, period-correct replacement. It suits drivers who prefer factory-style performance with an electric choke and vacuum-secondaries for street use, and for workshops that need a plug-and-play carburetor compatible with EGR-equipped systems. If you require a direct-fit Quadrajet replacement that balances drivability, build quality, and straightforward installation, this 1904R is targeted to meet those needs.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Does this carburetor support EGR systems?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. The 1904R retains EGR port compatibility for 1980–1989 Chevy 305\/350 setups.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is tuning required after installation?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Basic idle mixture and float level checks are recommended; no major tuning is typically required for stock engines.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Generic","offers":[{"title":"Default Title","offer_id":48081917837470,"sku":"B0FJ8GMDHT","price":193.84,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/generic-1904r-front-view.jpg?v=1785810059","url":"https:\/\/northtrailauto.ca\/products\/generic-1904r-rochester-quadrajet-4mv-4-barrel-carburetor-for-chevy-305-350-750-cfm-vacuum-secondary-with-electric-choke","provider":"North Trail Auto","version":"1.0","type":"link"}