What is it? New petrol engines for the world's best limo
On sale January
You'd think there was little else that could be done to improve the Mercedes S-Class, our favourite luxury saloon. Fortunately for buyers, the engineers in Stuttgart don't see it that way. Between now and January, four of the six engines will be replaced all with updated seven-speed automatic gearboxes; engine stop-start becomes standard; and there will be new optional features that actively prevent you changing lanes into the path of another car or drifting off-course unintentionally.
We've already reported on the new V8 in the S 63 AMG , and a more powerful 3.0-litre V6 diesel that meets 2014 emissions regulations with the aid of a chemical injection into the exhaust gases has just gone into the S350 CDI.
Here we're focusing on the two new direct-injection petrol engines a 302bhp 3.5-litre V6 and a 430bhp 4.7-litre twin-turbo V8 which bring spectacular reductions in fuel consumption and CO2 emissions.
The V6 is 24% more efficient than the one it replaces, for instance, and now emits the same CO2 as the diesel, while the V8 brings 22% improvements compared with its 5.5-litre predecessor. Yet both have more power and torque: lots more in the case of the V8, which develops its maximum pull at a diesel-like 1800rpm.
It's a magnificent engine, smoother than honey and almost silent when being driven as an S-Class should be, but with a latent potency that makes you wonder if the extra cost of the S 63 AMG is justifiable.
If the S350 feels more restrained in comparison, thats because it lacks the turbochargers of its larger stablemate and is not so well blessed for low-speed torque. It still ensures every journey is a combination of effortlessness and refinement, though. It might just tempt a few people previously sold on diesel to change their minds.
What Car? says
The petrol-engined S-Class fights back