Lexus began its F performance marque in 2007 with the IS F, a direct competitor to the E90 BMW M3. We quite liked the 311kW Japanese sports saloon and had an endearing relationship with one in our Fast Fleet. Then came the brilliant 412kW LFA supercar, followed by the BMW M4-battling RC F. Their latest model, the GS F, finally drops Lexus straight into proper super saloon waters, battling the likes of the BMW M5 and Mercedes-Benz E63 AMG.

But the spec sheet makes you wonder if the GS F brings enough muscle to the fight. Idealistic dreams of an E60 M5-like Lexus with the 9000rpm V10 from the LFA didn’t come to fruition. The GS F’s 5.0-litre V8 engine is shared with the RC F. Output is unchanged at 351kW and 530Nm of torque. That’s well off the 410kW+ mark set by the latest German competition, as well as Cadillac’s new 477kW CTS-V. At least the 1830kg Lexus comes in 115kg lighter than the heavy hitters from Deutschland. Plus, the lemming-like trend towards turbocharging means the honesty and linear throttle response of the GS F’s naturally aspirated V8 is welcomed.

Lexus GS F front three-quarter static

Before you question the environmental impact of this apparently antiquated setup, keep in mind the big Lexus V8 utilizes both Otto and Atkinson combustion cycles, improving efficiency. Figure the GS F’s combined fuel economy rating won’t be too far off the latest F10 M5’s 9.9L/100km. An eight-speed torque-converter automatic helps, routing the power to the 275mm rear tires and keeping the engine nearer idle speed during motorway slogs.

Lexus claims the GS F is equally content once you leave that motorway, even if the deviation involves a circuit. They state their latest sports saloon features a ‘genuine dual personality, equally adept at trimming lap times and the commute back home.’ The Torque Vectoring Differential (TVD) from the RC F comes standard, and should help. It’s a particularly trick setup, with electric motors, clutch packs, and planetary gears. No word on if the GS F steals the GS450h F Sport’s rear-wheel steering but we’re betting it will. We’ll learn all the details when the GS F is officially revealed at the 2015 Detroit auto show on 13 January.

Interior of the Lexus GS F