i was told at peak hp it was only drawing 650cfm thru the hat. I'll pull the dyno records and see what is said. I had a discussion with the engine builder/dyno operator re carb size. His opinion was the ideal carb size was 750 for this engine, but the 800 was close enough. He said everyone knows you want 25% more CFM than you use for the pressure drop. (I never heard of that, but he knew 100x more than I running a dyno for years)
The EFI's aren't supposed to hurt hp if oversized since the injectors send the fuel for what the motor sucks in, not what the fi is rated for. My concern is would say a 900cfm EFI have a greater pressure drop thus better acceleration that a 715cfm due to its increased size. This is similar to the double pumper mechanical sec carbs being faster than a vacuum carb due to the pressure from created when the throttle is snapped open. I'm unsure, since the EFI sprays fuel into the manifold verses being drawn from the boosters, if this advantage still applies. I need a Engine Masters video: 715 CFM EFI verses a 1000 CFM on the same 450- to 500 hp engine. Which accelerates harder? The same?
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