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Old School BBC with Twin Turbos and combo throttle body and multiport fuel injecion?

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Okay, so here's what I'm working on. As I work through the courses towards becoming a local tuner, I have my own project as well. It's a 71 Monte Carlo sporting a 468 BBC engine, twin s366 turbos, non-intercooled and running e85 and a Fitech throttle body EFI. The current engine has some blowby so I'm in the process of building a better replacement. It will be replaced with a 489 stroker plant, fully forged rotating assembly, about 9.5:1 compression ratio, and also running E85.

Here's where it gets interesting. The Fitech EFI system I have will not support what this combo will be capable of. However, it operates as a 2 stage batch fire injection with 8 injectors in the throttle body (4 running the first stage, all 8 running at higher load and throttle position on the 2nd stage). That being said, my plan is this; rewire all 8 injectors in the throttle body as either the 1st or 2nd stage, and add 8 more injectors into a multiport intake and wire those into either the first or second stage. Now you may ask why not just add bigger injectors and scrap this idea? The answer is because I like to do things just a bit different and be unique with my builds.

Couple questions. Is this idea completely ridiculous? And if it's not, which injectors should I wire on the 1st stage of injection and which injectors should activate on the 2nd stage of injection?

What kind of intake manifold are you going to have? A downdraft style or plenum style?

Injector staging is a big pain in the ass. The plumbing, getting a smooth injection transition and transient response are a lot of work. If you want a pain in the ass, go for it.

The manifold is open plenum style single plane with an injector bung built into each runner.

Yeah, it'll be a pain in the ass, probably, but so has everything else in this build and I welcome the challenge.