Of course, everyone really wants to know what’s under the hood. You’ll find the same cast-aluminum block that’s now doing business in the IS-F, but everything else about this DOHC 5.0-liter V-8 engine has been revised. Lightweight titanium valves are again matched with strong, forged connecting rods, but there are new cylinder heads that still incorporate variable valve timing on both the intake and exhaust cams. The polished crankshaft is smaller in diameter to reduce friction, while the pistons reduce friction as well. Naturally the intake manifold and exhaust headers are new, and the exhaust barks with a sharper, louder note. The dynamometer numbers aren’t yet final, but we’re told that this engine spins faster than before to deliver at least 450 hp and 384 lb-ft of torque.