What I'm saying is, engines aren't everything. But they are something, and in the peculiar case of the 2013 Audi S8—which I believe is the quickest full-size, five-seat production sedan in all the world, a siege cannon against the walls of imagination—I hope casual readers will forgive some talk of deck height, manifold routing and zero-lift cams in the interests of a larger point.
The S8 is a low-volume (about 8,000 cars globally) performance variant of the flagship A8 sedan. At $110,000 base MSRP, it's $29,100 dearer than the standard-wheelbase A8 with the regular 4.0-liter, 420-hp V8. Our test car came with more bells and whistles than the Singapore harbor patrol, including a $6,300 Bang & Olufsen sound system and an extended leather package ($5,500), which helped balloon the as-tested price to $125,995.
This and that, here and there, it all comes down to an engine upgrade: The S8 deploys Audi's astonishingly compact EA824, a direct-injection, bi-turbo, 4.0-liter V8 rather turned outside-in, with the exhaust plumbing routed between the 90-degree V cylinder banks, where dual twin-scroll turbochargers and the intercooler reside. The object is to shorten the exhaust paths to the turbochargers, ensuring greater thermal efficiency and response.
Be assured: It's responsive. This thing kicks like a velvet mule.
Read Article