McLaren To ‘Tweak’ MP4-12C Following Criticism By Huw Evans Jul 20 2011 Share this Article Tweet Most of the tweaks revolve around the 12C’s Intake Sound Generator which incorporates a butterfly valve, to regulate the amount of noise entering the cabin. Continue Reading... Filed under: British European Exotics McLaren Sports Cars TechnologyTags: exhaust notes, exotic cars, McLaren 12C, McLaren Automotive, running changes, visceral appeal