All-New 2.0-Liter Turbo Engine

The 2008 Lancer Evolution's 4B11 engine is an intercooled-turbocharged 2.0-liter DOHC inline 4-cylinder. Beyond that description, it differs greatly from the legendary 4G63 it replaces. The 4B11 is built with a reinforced cast-aluminum cylinder block versus the cast-iron block used in the 4G63, and aluminum is also used for the cylinder head and cover and the timing chain case. Unlike the 4G63, the 4B11 does not use a balancer shaft, made possible by the new engine's inherently lower noise and vibration and use of hydraulic engine mounts.

The new 4B11 T/C produces more power than its predecessor: 295 hp (est.) at 6,500 rpm (vs. 286 hp at 6,500 rpm) and 300 lb.-ft. of peak torque at 4,400 rpm (vs. 289 lb.-ft. at 3,500 rpm). The 4B11 T/C provides a broader torque curve, as well. A revised turbocharger yields up to 20-percent quicker response at lower engine speeds versus the 2006 engine's turbocharger.

A major divergence from the previous engine architecture is in the use of a direct-acting valvetrain in place of the roller rocker arm configuration for reduced weight. A timing chain replaces the belt, and MIVEC variable valve timing us used on both the intake and exhaust camshafts (the most recent 4G63 had MIVEC on the intake only). The rear-located (firewall side) stainless steel exhaust manifold helps improve weight distribution, and the freer-breathing exhaust system features a larger-volume main muffler with dual tailpipe outlets.