WHAT IS IT? A retractable hardtop version of McLaren's ferocious 12C.
HOW MUCH? $268,250 base, $321,080 as tested including sport exhaust ($6,330), navigation with Meridian sound system ($7,200) and Volcano Yellow paint ($5,400).
WHAT MAKES IT RUN? 3.8-liter V-8 with twin turbochargers (616 horsepower, 443 pound-feet of torque), 7-speed dual-clutch automated manual transmission.
HOW'S THE WARRANTY? Coverage for three years with unlimited mileage. That's right: on mileage, the warranty beats Hyundai's.
IS IT THIRSTY? Rated at 15 m.p.g. in the city and 22 on the highway, the 12C prioritizes performance over fuel economy.
Turbochargers make wonderful noises. A turbocharger is a lot like a miniature jet engine, but most car companies seem to think that drivers don't want to hear the LaGuardia taxiway as they're merging onto the highway.
That's a shame. I used to have a Saab 9000 Turbo with a low-restriction air intake, and its dominant aural signature was the Lilliputian Top Gun dogfight that erupted beneath the hood every time the turbocharger spooled up. Unfortunately, modern cars don't much let you hear their turbos at work.
Well, except for one: McLaren 12C, you're first in line, cleared for takeoff.
Squeeze the throttle on the retractable-hardtop 12C Spider and a symphony of howls and gurgles erupts from the mid-mounted, twin-turbocharged V-8 as unsuspecting air is belligerently funneled into the hungry maw of an 8,500 r.p.m. monster. The turbos issue a high-pitched whine under throttle, then dump excess boost with a breathy exhale. Maximum boost is a formidable 29 pounds per square inch, a statistic that helps to explain how a 3.8-liter V-8 generates a staggering 616 horsepower.
The Spider seemed decidedly more vocal than the coupe I drove last year, so I asked McLaren if anything was changed to uncork the intake cacophony. As a matter of fact, yes, there was. The 12C's Intake Sound Generator -- programmable by the driver -- is more aggressive, increasing the decibel level as the driver moves up through Normal, Sport and Track powertrain modes.
So then, what's an Intake Sound Generator? I asked McLaren's new chief executive, Mike Flewitt, who explained: "It's basically a tube with a valve in it, so it lets the sound pass through without carbon dioxide getting into the cabin. But it's not creating anything that isn't really there."
Mr. Flewitt did not mention BMW, but the latest M5 augments its V-8's soundtrack by playing engine noises through the car's sound system. The 12C isn't doing that. It's more akin to sticking your head under the hood, while you're driving, to take a listen.
Of course, if you want even more visceral exposure to the engine, you can wait 17 seconds for the hardtop Spider to transform into open-air roadster. The Spider uses the same carbon-fiber tub as the coupe, so the power roof exacts a weight penalty of only 88 pounds, for a still-svelte total of 3,033 pounds. The 0-to-60 m.p.h. time remains unchanged at 3.1 seconds, but over a quarter-mile those 88 pounds will slow you down, from a 10.6-second elapsed time to 10.8 seconds. (Trap speed drops from 136 m.p.h. to a still-impressive 134.) I think I could probably live with that. The Spider also gains a bonus auxiliary trunk -- the area where the top stows doubles as storage space if the roof's up.
As for demerits, the main drawback seems to be that the seam in the middle of the hardtop turns into a channel that funnels rainwater onto your head when you exit the car. The solution, which I'm sure many Spider owners will embrace, is to live in Malibu.
I drove in steady New England rain during my time with the 12C, which meant that I became frustratingly familiar with the car's traction-control system. On a wet road, the 12C has the power to effortlessly spin those giant rear tires at 45 m.p.h. But find a stretch of dry pavement, and a 12C coupe is one of the few cars that can outpace a 12C Spider. And even then, not by much.
It seems that the traditional tradeoff between coupe and convertible, wherein the droptop is an overweight, cowl-flexing Fat Elvis version of the coupe, no longer applies to certain carefully designed two-seaters, the 12C chief among them. In choosing between the two 12Cs, you'd find a Meyer-Briggs personality test more relevant than a stopwatch. Are you the type of person who's out on the Miley Cyrus side of the extroversion spectrum, the kind of person who's ready for the attention that comes with a roofless McLaren?
I'm not sure I require that level of hedonism. Roof up, windows down, a dry road and turbos singing: that sounds good to me. EZRA DYER
This article originally appeared in The New York Times.