Lexus V6 and V8 premium engines employ advanced techniques originally developed for motorsport to ensure high performance and extended durability with minimum noise or vibration.
All V-type Lexus engines use an unusually robust technology that adopts four bolts to secure the crankshaft in the aluminium-alloy engine block, rather than two bolts used in conventional engines.
The four bolts securing each Lexus bearing cap are made from high-tensile heat-treated steel.
In addition, a specific part of the unthreaded shank of each bolt is engineered to stretch a precise amount as the bolt is tightened, ensuring consistent, repeatable clamping forces.
“Four-bolt mains” were a modification originally employed by builders of racing engines to help standard production engine blocks resist the higher forces of combustion in competition engines modified with higher compression.
In some cases, builders also added two more bolts that were “cross-bolted” through the sides of the block into each bearing cap to resist lateral vibrations and add stiffness to the whole engine assembly.
All Lexus V6 and V8 engines have been engineered using a contemporary application of both these performance modifications.
Lexus Australia chief executive Scott Thompson said the combination of these motorsport-derived technologies underscored the Lexus commitment to perfection.
“As a result, owners experience the outright performance expected of a Lexus as well as the most durable engine,” Mr Thompson said.
“In addition, by reducing or eliminating potential noise and vibration at the source, these design features deliver the smooth, quiet ride that has become a Lexus hallmark,” Mr Thompson said.
Premium Lexus models in Australia are powered by V6 and V8 engines ranging in size from 3.5-litre V6 (IS, ES, GS, LS, RC, LC and RX), 4.5-litre V8 (LX 450d), 5.0-litre V8 (LC, RC F and GS F) and 5.7-litre V8 (LX 570).
V-type engines arrange their cylinders in two rows of three cylinders angled 60° apart for V6s, or two rows of four cylinders at a 90° angle for V8s, making very compact overall packages.
The crankshaft at the bottom of the V rotates in main bearings secured deep into the engine block by a series of bearing caps, four bearings for V6 engines and five bearings for V8s.