One glance at this new Lexus' slinky profile, fat tires, and bulging rear haunches suggests it's a pretty loving homage to BMW's M4 coupe. Move around front, however, and the similarity ends with a visage that is the polar opposite of a jovial Bavarian. Chief engineer Yukihiko Yaguchi confirms that while his baby will compete on price and performance with the M4, Mercedes C63 AMG, and outgoing Cadillac CTS-V (or forthcoming ATS-V) coupes, in terms of personality and soul it will feel as removed from those cars as a Wagnerian opera is from Kabuki theater.
And the distinctive personality he's referring to is far more than skin deep, deriving largely from the still naturally aspirated 5.0-liter V-8 engine that's now a segment exclusive. This engine shares only its basic cylinder block with that of the outgoing IS F sedan. The cylinder heads and all moving parts are completely new. Friction reductions allow the engine to rev 500 rpm faster than the IS F's, to 7300 rpm. A switch to electric phasing on all four cams brings greater variability and precision, and lets the engine borrow the Prius' more efficient Atkinson cycle operation during low-demand cruising conditions. So, while BMW downsized its M3/M4 engine from a 4.0-liter V-8 to a 3.0-liter I-6 and added twin turbochargers to compensate, Lexus virtually downsizes its 5.0-liter V-8 to roughly a 4.2-liter just by leaving the intake valves open for part of the compression stroke during Atkinson operation.
The ideal Atkinson cycle captures and compresses an amount of air that, when combusted and expanded throughout the entire power cycle, results in a cylinder pressure that's near atmospheric at the bottom of the piston's stroke, meaning the engine has wrung every bit of energy out of the fuel. Drop the hammer, and those valves shut in time to give you the full 12.3:1 compression (up from 11.8:1) and 5.0 liters of furious power -- at least 450 horses' worth (up substantially from the IS F's 416). A newly modified version of the current D4S direct-injection with secondary port injection helps make all this work. Torque ratings and further specifications are pending.
Power and twist route aft through a similar eight-speed automatic, upgraded with different control logic for D-mode operation, and a track-optimized Sport-plus shift schedule. Naturally, a manual mode relinquishes full control to the driver's shift-paddling or stick-rowing pleasure. At the rear axle is a torque-vectoring differential that can be programmed via the TVD switch on the console for standard, slalom, or track vectoring. That middle position optimizes for very quick side-to-side transitions found in magazine slalom tests and autocross courses. The rotary knob marked Eco, Normal, Sport controls throttle response, shift-schedule in Drive, and the electric power steering feel. The suspension is not adjustable.








