I'm with eddie, use the LS head, and get a 4-2-1 header of your choice. Some headwork, skunk2 manifold, crower valvesprings & retainers, cam gears, and some crower 404's. Throw a GSR tranny on that, and it'll be decently quick. It should be said that whether or not you use the LS head, you have to use the LS intake manifold since the B20 has the "giraffe" intake manifold.
If it was me, I'd either go turbo, or the above setup with some juice
But I'm a nitrous fiend
h:
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2015 Ford Mustang GT Fastback - Ingot Silver - 6M - Performance Package - Gibson Catback, JLT CAI, FR 47lb injectors, BAMA E85 tune, Eibach Sportline, BMR wheel hop kit, UPR oil separator, Steeda shifter bushing/bracket
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