LEXUS has completed a turbocharged treble with its announcment of a new engine for the popular IS saloon.

It sees the model adopt petrol turbo power for the first time in the shape of the new IS 200t, the third variant to be given the powerplant following the NX 200t crossover, which is already on sale, and the future RX 200t SUV.

In the IS the 2.0-litre unit will drive the rear wheels through an eight-speed Sport Direct Shift automatic transmission with paddles, originally developed for the RC F high-performance coupe.

Delivering a hefty 241bhp, the car can accelerate from 0-62mph in seven seconds and on to a potential top speed of 143mph, while average fuel consumption is from 40.4mpg.

Lexus says the engine benefits from a host of innovations and technologies that secure fast throttle response, instant pulling power, minimal turbo lag and strong fuel economy.

Key elements include D-4ST fuel injection and a water-cooled cylinder head with integrated exhaust manifold and twin-scroll turbocharger.

And because turbo engines tend to be noisy when the throttle is closed - the effect known as turbo sigh - Lexus has used an electric air bypass valve and resonator to reduce the characteristic turbo noise.

As a turbocharged engine requires a smooth intake flow for performance, the Japanese brand's engineers focused on creating special duct shapes that deliver power without noise.

The IS 200t will be available to order from September and UK specifications and prices will be announced nearer the on-sale date.