Mike I’ve been kind of thinking about this since I read your post this morning. It seems to me that as the throttle bodies are only passing air that a simple option might be to simply disconnect the secondary throttle plate linkage and build progressive linkage for the TBs.

Basically you would now have 2 500 CFM TBs (1000 CFM total). Using progressive linkage to the secondary throttle body would determine when and how much additional air is allowed into the engine. How you design your linkage will determine the kick in point and total amount of air the secondary TB will provide. In theory the secondary TB should be almost infinitely adjustable to provide up to an additional 500 CFM.



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