McLaren promises the droptop has all the track-flavored performance of the 600LT coupe, with the "added exhilaration of open-air driving." With a top-down top speed of 196 mph, that's a lot of added exhilaration. (It's 201 mph with the top up.)

And just imagine the tune from those top-exit exhausts just aft of your head.

McLaren says it managed to limit the weight gain in the Spider to 110 pounds over the coupe, and cites a dry weight of 2,859 pounds. Well, 2,859.4, to be McLaren-exact. That's 220 pounds lighter than the 570S Spider from which this car is derived, and lighter than its exotic competitors. Customers can also order their cars with seats from the Senna and with radio and climate control delete for maximum weight loss. Much of the weight savings credit goes the car's carbon fiber MonoCell II chassis that, even with the roof cut off, remains as rigid as the coupe without any added reinforcements.

As for power, McLaren cites 592 hp and 457 pound-feet of torque from its 3.8-liter twin-turbo V8. That's 4.82 pounds per horsepower, for a 0-to-60 time of 2.8 seconds, on par with the coupe. You surely won't even notice that the Spider's time to 200 kph (124 mph) at 8.4 seconds is 0.2 seconds slower than the coupe.

All that power is delivered by a dual-clutch seven-speed transmission. An Ignition Cut feature in Sport mode is said to facilitate faster shifting "whilst delivering a dramatic aural crack from the top-exit exhausts." A feature called Inertia Push (isn't all driving an inertia push?) is supposed to boost acceleration in Track mode.

The retractable three-piece hardtop can be operated at speeds to 25 mph. It stows into a tonneau cover behind the seats that can provide a bit more storage when the top is up.

And even the Pirelli P Zero™ Trofeo R tires are bespoke, "for track-focused dynamics."

The Spider is available to order now, starting at $256,500.

McLaren divides its street cars into three categories: Sport Series, Super Series, and Ultimate Series. The LT designation, which stands for Longtail and memorializes the collectible F1 Longtail of the 1990s, is affixed to higher-end, track-focused machinery. The 600LT sits at the very top of the brand's entry level series, and while that seemingly means it's merely the biggest and baddest of the lowest tier, that isn't a fair assessment.

Now that we've driven the 600LT Spider, however, we might have to adjust our rankings. Unlike some supercar makers, McLaren prides itself on building vehicles that aren't just fast around a racetrack but are somehow also easy to live with and drive out in the real world. That dual-role nature lends itself extremely well to top-down motoring. And McLaren has nailed the folding hardtop design with the 600LT Spider.

With the top up, the McLaren 600LT Spider feels just like the coupe. The electrically powered roof is composed of three pieces that can raise or lower in less than 20 seconds and can be activated at up to 25 mph. At speed, the hardtop does a good job of keeping the cabin relatively quiet, and conversations can easily be had on the highway.

Top down, there's less wind buffeting and a greater feeling of spaciousness than in the Lamborghini HuracanSpyder. A power-operated rear window is a great feature that can further cut down on wind intrusion, or retract fully in order to let as much of the engine's soundtrack into the cabin as possible. And thanks to exhaust pipes that exit through the top of the engine cover, there's plenty of sound just aft of the driver's seat waiting to be enjoyed. I left the top and rear window down most of the time despite the unseasonably cool temperatures in and around Phoenix.

At idle, McLaren's force-fed V8 engine doesn't sound particularly menacing. I might even be tempted to call it a bit agricultural if I didn't know about all the advanced engineering that goes into building such a powerplant. As with every other McLaren I've driven, there are constant unidentified sounds coming from every corner of the car, from random buzzes up near the frunk to what sound like servo motors from somewhere in the cockpit. Once underway and with a few thousand revs showing on the tach, things start sounding less like a room full of mechanical clocks and more like a proper supercar.

Ripping through the gears in any McLaren is a blast. Shifts from the steering wheel-mounted paddles fire off more quickly than I'd ever be able to match with a clutch, though I do miss the ability to show off by blipping the throttle from time to time. Acceleration from the 600LT doesn't feel as unearthly quick as the 720S I drove the day before, but it's still extremely fast. 0-to-60 takes 2.8 seconds. 0-to-incarceration is a precious few ticks longer. McLaren says the 600LT will hit 201 mph with the roof up, or a much more exhilarating 196 mph with the top stowed away.

But numbers aren't really what the 600LT Spider is all about. It's designed to be enjoyed primarily at the race track, and it's in this duty that McLaren's latest Spyder really shines. My test car wasn't the lightest 600LT Spider McLaren can build — the quoted dry weight of 2,859 pounds (219 pounds lighter than the 570S Spider but 110 pounds heavier than the 600LT hardtop) is achieved with the MSO Clubsport Pack and without air conditioning or an infotainment system — but that hardly mattered as I slowly improved my own laps of the 2.26-mile, 16-turn course at Arizona Motorsports Park. It didn't take long to start braking later, turning in more aggressively and rocketing out of each corner with greater authority and thrust than the one before.

The 600LT Spider's steering is perfectly weighted and super precise, benefiting from hydraulic power assist instead of the electric racks that dominate the automotive world today. That steering feel, combined with very good visibility — particularly considering the low-slung nature of supercars in general — means it's easy to accurately place the 600LT's wheels exactly where you want them on the track. And the suspension is just compliant enough that a trip over trackside curbing doesn't upset the chassis. McLaren says the Spider can haul itself from 124 mph to a standstill in 397 feet. The carbon ceramic brakes felt great lap after lap, and just as strong at the end of the day as they did at the beginning.

I drive lots of fast cars, but I'm not a race car driver. My ability to have fun while improving lap times from behind the wheel of a supercar on a race track is all about confidence. The fact that the 600LT Spider manages to have extremely high limits without feeling like it's out to kill you inspires the kind of confidence needed to keep pushing the limit. That's exactly what I'd want if I could afford a McLaren tailored for track duty — the 600LT will reward your continued effort and make you a better driver.

The fact that the 600LT Spider is designed primarily to fling as quickly as possible around a race track does knock a few points off its street-driving score. Its bucket seats are locked into attack mode, so it takes a little while to find a comfortable driving position through primarily steering wheel adjustments. Even when I got myself relatively happy behind the wheel, long highway stints were still compromised by the unadjustable buckets that cannot recline.

A 7-inch vertically oriented touchscreen is used to control the 600LT Spider's infotainment system, but it's an older design than the one used in the 720S. It's slow, and the resolution and colors don't give off a premium vibe. I eventually gave up on the in-car navigation and used Google Maps on my Android-powered smartphone instead. Of course, those gripes are equally volleyed at the 600LT coupe. And when the sun was out and the weather was nice, dropping the Spider's top and stomping its accelerator pedal made me forget them all anyway.

For $256,500 here in the United States, the McLaren 600LT Spider costs about $15,000 more than the hardtop, and I think it's a bargain. The $308,859 Lamborghini Huracan Performante Spyder is also designed for the race track and offers a similar performance envelope to the 600LT Spider (apparently arachnids in the U.K. spell their names differently than those in Italy), with more horsepower but less torque, and a slightly slower 0-to-60 time but a top speed that's a single mile per hour higher.

Are supercar buyers basing their purchase decisions primarily on price? No, probably not. But the fact that we're splitting hairs between the 600LT Spider and the Huracan Performante Spyder, which is itself a track-bred supercar benchmark, proves just how impressive McLaren's newest model is. And just think of how many sets of the car's bespoke Pirello P Zero Trofeo R tires that $50,000 difference can buy. Because if you use the McLaren 600LT Spider as it's meant to be used, you're gonna need 'em.