2010 Lexus IS 350C F-Sport Full Test and Video

"Yo, dawg! That Lexus is effed-up, yo!"

The young man in the crosswalk seemed very insistent. For a moment we thought he was referring to the sheer number of Lexus F-Sport accessories ($12,471 worth, so indeed F-ed to the maximum) with which our $44,815 2010 Lexus IS 350C had been modified, but upon reflection we believe he was simply complimenting the pleasing aesthetic that, in his estimation, they brought to this hardtop convertible.

Struggling for the proper reply that would validate our newfound street cred, we were unfortunately possessed by the spirit of Opie Taylor. "Thanks!" we said, and we were barely able to refrain from adding, "Mister."

"True dat" and "Werd" mysteriously deserted us when we needed them most.

F-ed, Only in a Good Way
G-Money is right. This black-on-black 2010 Lexus IS 350C F-Sport looks serious, especially with its top in place.

All the bits here are available from the Lexus catalog of F-Sport accessories, the wide selection of aftermarket-style equipment that Lexus has developed in its effort to make the IS range of cars signify speed instead of just style. Of course, style still has a lot to do with it, as these graphite-gray, forged-aluminum 19-inch wheels and low-profile Michelin PS2 tires ($2,346) are dramatized by the lowering springs ($299) and Bilstein dampers ($740). The added menace of this IS 350C's obsidian black paint makes the effect even more intriguing. All hunkered down, dark and mysterious, this is the most masculine Lexus convertible there is.

But the IS 350C F-Sport doesn't thrive on its good looks alone. Beneath the skin, the F treatment provides measurable gains in performance with only a little loss of comfort. In its standard form, the 2010 Lexus IS 350C reminded us of a rolling golf resort. Now we'll see how well it represents a high-performance coupe.

Inevitable Comparisons
Because the 306-horsepower, folding tin-top IS 350C weighs almost 800 pounds more than the equally powerful IS 350 sedan on which it is based, the heavier F-Sport convertible is naturally a little slower on the drag strip — about a half-second separates the IS sedan from the drop top across the board. Our black test car's best 0-60 time is 5.9 seconds (5.6 seconds with 1 foot of rollout like on a drag strip) and the quarter-mile elapses in 14.2 seconds at 97.3 mph. Nevertheless, this performance puts it in almost a dead heat with the 2009 Infiniti G37S Convertible.

Lexus tells us that the 60mm stainless-steel axle-back exhaust system ($1,470) from the F-Sport catalog is partially responsible, since it adds up to 1.5 percent more power, while the less restrictive intake system ($455) is ideally good for another 3 percent. In other words, $1,925 potentially buys you (are you ready for it?) almost 14 horsepower — and an exhaust note that can grow tiresome. This is a genuine improvement and what you usually get with less restrictive intake and exhaust modifications for any car, but we'd spend that money elsewhere.

Compared to the 2008 Lexus IS 350 Sedan we last tested, this 2010 IS 350C F-Sport also stops shorter by 2 feet. You can't deny that this car's F-Sport Brake package with lightweight, two-piece, cross-drilled rotors with forged six-piston calipers in front and four-piston calipers in the rear plus high-performance brake pads combine to deliver exceptional feel and fade resistance (in fact, the car's shortest stop arrived on the seventh attempt), but we're conflicted about this upgrade. The standard brakes are already excellent and that's a lot of Benjamins for improved feel and a cool aesthetic, yet the F-Sport package is what you'd want for serious high-speed work.

Money Well Spent
If you're looking to spend good money on a modified IS convertible, look no further than the $2,346 wheel/tire upgrade and add it to the $1,588 for springs, shocks and antiroll bars. The resulting $3,934 is a reasonable amount to spend on the 2010 Lexus IS 350C's chassis, and here's why.

The forged-aluminum wheels reduce unsprung weight by 21 pounds (5.5 pounds at each 19-by-8-inch front wheel; 5 pounds at each 19-by-9-inch rear wheel), plus they look undeniably cool. Combined with supple Bilstein dampers, the new springs reduce ride height by 1.3 inches in the front and 0.9 inch in the rear. The antiroll bars are 105 percent stiffer up front and 320 percent stiffer in the rear. What does this all mean? It means the lower chassis is more responsive, the handling balance is a little livelier and the tauter suspension calibration works the new Michelin Sport PS2 tires harder.

As is usually the case with such suspension kits — especially when they're applied to convertibles — we were guardedly optimistic (a.k.a. "suspicious") about this one's ability to deliver a car that works well both at the track and in the real world. But the F-Sport hardware comes through.

With a slalom speed of 68.2 mph and an average lateral acceleration of 0.89g around the skid pad, the 2010 Lexus IS 350C F-Sport has improved by 1.4 mph and 0.02g respectively over the much lighter IS 350 sedan. Moreover, there's only a negligible decline in ride quality and almost no increase in road noise. What's more, the convertible's sturdy structure doesn't mind the added firmness and remains taut and rattle-free. Better grip, more control, better stance and virtually the same ride qualities. Sign us up.

Steering Committee
With this added capability, we'd like more information coming to us through the steering wheel. Part of this car's issues can be traced to the standard IS 350's electric-assist steering, which doesn't communicate changes in load or grip very well. But there's also a lack of response that feels as if it could be remedied with a steering ratio quicker than the standard car's 14.6:1.

Though the F-Sport IS convertible goes through the slalom cones at a stunning 68 mph, we have to crank the steering wheel through a half turn of lock to weave from one slalom gate to the next, and that's too much. Even during sessions of canyon carving, we were dismayed by the amount of steering lock required to negotiate tight turns. The F-Sport seems so much like a genuine sport sedan in the corners that we think it ought to steer like one as well. (Of course, we know that there's no $50 part that's going to do the job.)

Not So Effed-up After All
If you're looking for a well-mannered convertible, we'd suggest you add the $3,934 for the Suspension package, wheels and tires to the $44,815 you'll spend for a base model 2010 Lexus IS 350C, giving you a total of $48,749. From there, we'd suggest the $1,040 ventilated and heated seats — this is a convertible, after all — and the Mark Levinson premium audio paired with the navi for $3,890.

As for the rest, the $865 carbon-fiber engine cover and $95 shift knob are merely for show. The $1,925 intake/exhaust systems produce no noticeable gains in real-world performance, although you might be entertained by the pronounced intake warble and droning exhaust note. The $5,652 brake upgrade seems steep, and might be worth it if you can afford it. But for our money, spend the $3,934 on wheels, tires, springs, dampers and antiroll bars. The chassis is rigid enough to handle the added stiffness, the handling gains are measurable and the ride qualities are still well within acceptable limits.

Although you could spend a bit less money for aftermarket hardware instead of F-Sport accessories, these Lexus-built bits carry a warranty. When installed by a Lexus dealer, F-Sport parts have a 12-month/12,000-mile warranty or the balance of the new-car warranty at the time of installation (four years/50,000 miles), whichever is greater. If a dealer does not install the F-Sport parts, the parts warranty is 12 months/12,000 miles.

Convertible or Coupe?
With the exception of its 204-hp engine, we liked the F-Sport equipment on a 2009 Lexus IS 250 Sedan we tested a while back, and similar equipment impressed us this time on an IS 350C so much that we'd love to see how well the F-Sport suspension would work on an IS 350 sedan.

And until we can gather a $44,815 2010 Lexus IS 350C, a $51,525 2009 BMW 335i Convertible and a $44,765 2009 G37S Convertible together for a proper tournament, the only conclusions we can make now are that Lexus has priced the new IS 350 convertible correctly, outfitted it properly and offered truly well-developed F-Sport upgrades to give it a chance of being a real contender against such worthy competitors.

The worthiness of the 2010 Lexus IS 350C F-Sport really comes down to the kind of car that you want it to be. If you want a great driving convertible, then be smart about choosing the kind of accessories that make the top-down experience better. And if you want a real Lexus coupe, a car that makes a statement about performance, then make your IS as effed-up as possible, dawg.

The manufacturer provided Edmunds this vehicle for the purposes of evaluation.