The 456M (M standing for Modificata) was unveiled in 1998, starting with chassis number 109589. Many changes were made to improve aerodynamics and cooling and the interior – still featuring Connolly Leather – was refreshed with new seats and other conveniences (fewer gauges on the dash, and a new Becker stereo fitted in front of the shifter rather than behind as in the very shallow and special Sony head unit in the 456 GT). The 456 had a smaller grille with fog lights outside the grille. The undercarriage spoiler on the 456M is fixed, where the older 456 had a motorised spoiler that began its deployment above 105 km/h (65 mph). The bonnet was the first commercial application of carbon fibre, the previous being made of a composite material. Power output remained unchanged on the Modificata using Bosch Motronic M5.2 engine management at 442 PS (325 kW; 436 hp); the cylinder firing order was changed for smoother running and the torque remained the same for later versions of the 456 GT.