New or redesigned parts include:
Cylinder heads and cam covers
Crankshaft: crank pin diameter, connecting rod big-end bearing size and crank counter-weight size are all reduced, to reduce reciprocating weight
Crank main bearings and caps
High-strength forged connecting rods
Pistons and piston rings
Titanium inlet and exhaust valves
Intake manifold and throttle body
Redesigned Variable Valve Timing-intelligent Electric motor (VVT-iE)
Revised Lexus D-4S dual injection system
Four-into-one exhaust headers and heat insulators
Oil pan and baffle plate
Alternator clutch system
Engine and transmission oil coolers
Spark plugs

Digging Into the Metal
The new cylinder heads improve the 2UR-GSE engine’s breathing with improved porting and a high-flow/high tumble ratio. In addition, intake surge-tank capacity has been optimized, as have the intake manifold runner length and diameter.
The new oil pan baffle shape reduces agitation and hence friction, while new air-to-oil coolers for the engine oil and transmission fluid increase track suitability.
The Lexus D-4S dual-injection system has been redesigned, with higher injection pressure of 2,611 psi and improved fuel atomization.
The throttle diameter was increased by 10 percent, from 3 to 3.3 inches (84 mm).
A new intake camshaft profile increases valve lift and suits the Atkinson cycle, while improvements to the electronic VVT-iE system have expanded its range of operation for increased fuel economy and performance.
New four-into-two exhaust headers help reduce interference and hence further improve engine breathing. The larger-diameter exhaust system is designed to reduce backpressure and sound amazing, especially under acceleration. At the same time, the main muffler keeps things from getting too rowdy at lower speeds.
As a final touch, the new 2UR-GSE engine has a one-way clutch on the alternator pulley.