Spied: 2015 Lexus IS F Coupe...or is it an RC F Coupe?

The Lexus IS Sedan was fully and dramatically recast as a third-generation offering for 2014, and now a new, 2-door version of the car has been spotted testing in Europe. While there's currently some question as to whether this model will retain the current IS nomenclature or arrive carrying a new RC designation, there's no doubt the version seen here happens to be a prototype of the hot F Coupe variant which Lexus is grooming as a rival to the upcoming BMW M4.

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Even clad in a full body wrap, it's obvious this Lexus super coupe-to-be retains a good number of key styling cues seen on the Lexus LF-CC Concept revealed at the 2012 Paris Auto Show as a precursor to this new IS 2-door variant. Here, the prominent signature spindle grille is flanked by even bigger air intakes, although the headlamps on this development vehicle appear to be more conventional than the 3-element LED units on the LF-CC. The F-spec prototype also sports a functional hood scoop and air extractors on its more highly contoured front fenders along with an aggressive wheel/tire/brake fitment. While the roofline appears unchanged, the short decklid on this test mule boasts a more prominent spoiler lip than the LF-CC, and its less-elaborate lower diffuser incorporates F-style "stacked-and-staggered" dual twin exhaust outlets.

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At the moment, there's still a good deal of uncertainty as to what will be attached to the other end of the 2015 IS/RC F Coupe's free-flowing exhaust system. The LF-CC featured a gas/electric hybrid powertrain based around a 2.5-liter 4-cylinder direct-injected engine, but that option is not in play for the upcoming F Coupe. One possibility is that this enthusiast-grade iteration will pack a hotter version of the existing 5.0-liter/416-horsepower naturally aspirated V8 used in the carryover 2014 Lexus IS F Sedan, which was not part of the Gen III makeover. Another is that, like the upcoming M4, the engine in this new Lexus will be smaller - think 3.5 liters -- and have just six cylinders. However, unlike any 6-cylinder motivators used in standard-issue examples of the 2-door, the one in the F Coupe would almost certainly be augmented by some type of power-boosting forced-induction system.

Beyond its potential switch from IS to RC badging, there's still no definitive word on whether the new Lexus F Coupe will spawn an equally potent drop-top sibling. At present, it seems increasingly likely that successors to the current (and also carryover) IS 250 Convertible as well as the IS F Sedan will be refloated on the new, third-generation IS platform at some point. We should know more in November, when a baseline version of this new Lexus Coupe is slated to debut at the Tokyo Motor Show. A production version of the high-performance F-spec variant is expected to make its first public appearance next January in Detroit.

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