I change my curve when I use e85 vs pump gas and I change it when I add or remove boost. Efi done correctly, and I don’t mean TBI, is almost always worth it. A good stand alone, multi port (Holley terminator or dominator, megasquirt, AEM infinity, etc) is very hard to beat. But they must be installed with a level of detail most people are not willing to do. Also, the incompetence of the tuner is a real thing. The amount of information and available changes that can be made even just in cold start is truly mind boggling. For instance, on my AEM infinity, there are 5 different “trims” (modifiers) for fuel and spark that are active just for CRANKING. 0-500rpm. It’s not for the faint of heart, but every single one I’ve done was well worth the effort.
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Quick shot of the cranking trims.