The b20 can still handle boost. It's a common misconception that they have weak sleeves. I've seen people running 15+ PSI on stock sleeves. It's all in the tuning.
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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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