Rumors about Lexus->ke47 working on a new generation IS sedan have been around for awhile, but this is the first time a mule of the next IS->ke500 has been caught testing. The mule is still wearing a modified body of the current generation, but it sits on a new platform, a new drivetrain, and a new suspension.

This beginner mule was the first move towards keeping the new design language hidden from all of us camera-happy journalists, but it still can't keep us from speculating a bit on the new model. The next IS will feature the same design language as the recently announced GS->ke439 and LS->ke436. Under the hood, it has been rumored to feature a 2.5-liter naturally aspirated 4-cylinder and/or a 3.6-liter flat-6 engine. The 2014 Lexus IS F will continue with a high-powered V-8 with an output of more than 400 HP. The IS-F will sprint from 0 to 60 mph sprint in about 4.5 seconds and will hit a top speed of about 170 mph.

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