I've read mixed reviews about the Motordyne manifold. Some people report that they didn't get any gains from it, and some people actually lost torque in the midrange by a fair amount, just to gain 2-3 hp at the very top end. Make sure you do your research before you pull the trigger. If you're gonna get it, then I would wait like Footloose said. Otherwise, you don't NEED a tune, but you can definitely benefit from it.
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