This summer, Rolls- Royce Motor Cars will begin production of the Phantom Coupé (www.rolls-roycemotorcars.com), a hardtop sibling to the Drophead Coupé. The Phantom Coupé features rear-hinged suicide doors and an optional brushed stainless steel finish, and it has the same 6.75-liter V-12 that powers the convertible. However, increased structural rigidity and stiffer rear dampers produce a firmer ride, and a more substantial rear antiroll bar further reduces the Rolls’ trademark “waftability.” The Phantom Coupé can reach 60 mph in 5.6 seconds en route to a top speed of 155 mph. The interior includes optional “starlight headlining,” which uses fiber optics to make the roof resemble a starry night sky. The feature begs the question: Who needs a convertible? . . .