4 Throttle Body Injection



Let talk Performance:

The 4 TBI setup is not about fuel economy….its about power.   Our Throttle bodies are bored to 1.25″ on the 2 and 4 TBI versions to provide maximum airflow, fuel delivery and power.   We did not design this system for racing since crank triggers are not allowed, but if you want good pull with plenty of top-end… this is your system.  We program the ECMs for the middle of the road engine setups, but this kit will require a laptop to tune your engine further.  All of our kits are supplied with NBO2 sensors, but support the use of Wideband O2 sensors (purchased separately) is highly recommended for advanced tuning and precise fuel control of these engines.  

The 4 throttle body system uses the standard Corvair Throttle linkage and the 4 carb air cleaner system.  It does NOT use progressive acceleration as the injectors evenly distributing fuel through the 4 throttle bodies to give a better and smoother response.   All 4 injectors are working to avoid stutter at “tip-in” and proper adjustment and maintenance of the TPS/MAP are imperative for the proper operation of the 4x TBI kit.  The Direct linkage system for the 4 Throttle body kit which opens all 4 TBIs evenly using a standard 2 Carb linkage.  

If you are interested in more power than a conventional setup, but want decent driving around mileage,  you may want to consider the Dual TBI kit with block off plates or install “thin plates” under the secondaries of the 4x kit to keep the quad look.  




The 4 Throttle body Injection system can also be used on engines that have had the extra Carburetor pad added (Fitch type).    The Throttle body injection unit uses the standard Corvair gaskets, but will need insulators to ensure the proper height of the TBI.  

Ignition:  We only offer the single-type ignition for the Four TBI kit. 

Kit includes all items from the fuel pressure regulator to the engine. Fuel Pumps and return line are NOT included. ** – Usable cores are required. See Cores Page.