From the moment you touch the dash-mounted “Start” button, the strengths of the LS’s new V8 are readily apparent. For one thing, this sophisticated motor is so smooth and quiet that you’ll find yourself stealing a look at the tachometer just to make sure it’s running. Head out on the road and put your foot into it, however, and the new engine jumps to life with brisk acceleration that makes the company’s 5.4-second 0-to-60 acceleration estimate feel just about right. To add a hint of character, there’s even a nice subdued growl when you get on the gas hard.