Big power modified monsters at Tokyo Auto Salon

Nismo GT-R Racing Concept. Photo / Supplied

The big Japanese carmakers were all on show at the modified car section of the 2011 Tokyo Auto Salon, claimed by organisers to be world's largest custom car show.

Toyota led the way, displaying 17 new models including an outrageous "racing" version of its tiny iQ city car developed in partnership with Gazoo Racing and MN Tuning.

The car, which has a new supercharged engine and roll cage, is a follow-up to Gazoo's tuned iQ from 2009, which sold out its limited production run in Japan.

Called GRMN iQ Racing Concept, it has an aggressive bodykit with large wheel arches and front air intake, chin spoiler and a rear wing. It also has lightweight racing wheels and a twin exhaust system.

Lexus showed off a shocking orange, lightweight racing version of the IS-F sports sedan, dubbed CCS-R (circuit club sport racer) and boasting carbon-fibre body panels and aerodynamic improvements. Lashings of carbon-fibre are on display on the dashboard, door trims and console.

The car's track intentions are confirmed by its safety harness, lightweight roll cage and reinforced frame. The car weighs in at 1420kg, a hefty saving over the standard IS-F's kerb weight of 1700kg. The 5-litre V8 from the standard car has been tweaked subtly, with an output of 324kW, an improvement of 13kW. The car has been entered into this year's Nurburgring 24-hour race, following Lexus' strong performance at last year's event with its Gazoo-tuned LFA supercar.

Speed-hungry Nismo unveiled a hardcore race version of the Nissan GT-R, called the Nismo GT-R Racing Concept. It followed Lexus' lead, using a lightweight carbon-fibre body with roll cage, bigger brakes and slick tyres.

The GT-R RC is kitted out for endurance racing, stripped of weight but carrying an on-board jack system and a 120-litre fuel tank.

The Nissan stand also featured a modified version of its Leaf electric car, called the Aero Style Concept. The car features a slick bodykit that, according to Nissan, "expresses an image of futuristic sport EV driving".

Honda revealed the TS-1X, based on the company's CR-Z hybrid coupe. Finished in menacing matte black, the TS-1X features stiffened suspension and a more rigid body.

Subaru lifted the covers from its WRX STI Nurburgring race-spec version, which the company hopes will take out the 2-litre turbo class at the 24-hour event.