The M5 uses a twin-turbo 4.4-litre V8 with 600bhp in its most powerful guise, the E63 AMG features a twin-turbo 5.5-litre V8 with up to 585bhp and the XFR-S is powered by a supercharged 5.0-litre V8 with 542bhp.
Those GS F engine outputs are for the US version of the car seen in Detroit, with European versions set to follow later this year. In the US, the GS F will also line up against the new 640bhp 6.2-litre supercharged V8 Cadillac CTS-V, which makes its world debut at the Detroit show.
The GS F’s V8 will send drive to the rear wheels through an eight-speed automatic gearbox, which features a manual shift mode.
Lexus says the GS F has had its chassis stiffened over that of the standard GS saloon on which it is based. The chassis will feature “structural reinforcements and an exclusive suspension package [strut and multi-link] designed to optimise the car’s handling capabilities and ride quality”.
Weighing in at 1830kg, the GS F undercuts the BMW M5 by 115kg and the E63 AMG by 40kg, making it the lightest model in its class.
The GS F is equipped with Lexus’s Torque Vectoring Differential as standard. It includes three modes: Standard, Slalom (which improves steering response and agility), and Track (for circuit driving).
Design wise, the GS F builds on the look of the standard car and features several aggressive-looking F aerodynamic and styling additions, including new front and rear bumpers, flared wheel arches, side skirts, a rear diffuser and a subtle lip spoiler. Quad exhausts feature at the rear.
The GS F rides on 19in alloy wheels front and rear. The front wheels are shod in 255/35 R19 tyres while the rears use 275/35 R19s.
The GS F is the second four-door saloon Lexus’s performance F division has created after the 2008 IS F. F division was also responsible for the V10 LFA supercar and the new RC F coupé, which is now arriving in the UK for sale.
Pricing has yet to be revealed for the GS F as it is still some way from its European launch, but expect it to cost around £80,000 when it arrives towards the end of 2015. The high price will in part be justified by the high level of standard kit Lexus will offer with the car.
Following the GS F is likely to be a four-door version of the RC F, the IS F, which will feature identical underpinnings to those of the coupé but a slightly lower price tag. Expect to see the IS F "sometime in 2016", according to sources. This may well be followed by a convertible version of the RC F.
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