Cadillac has butched up its sassy four-door CTS and created one of the planet's maddest rear-wheel drive luxury sports saloons. Unsurprisingly, the CTS-V will be a rare sight on British roads. Availability will be limited on a special-order basis and there's no right-hand drive option. Cadillac is pinning sales hopes on its more modest right-hand drive CTS stablemate (see road test) while the V-Series exists to prove the US manufacturer can turn out stunning performance cars with a touch of luxury.At around £45,000 I'd expect a lot of luxury and performance. That's £15,000 more than the most expensive CTS 3.6 Sports Luxury for a car with the same proportions as the cooking CTS. But it delivers in bucketloads.Anyone looking for a latterday Lotus Carlton can apply here. The CTS-V is a brutal heavyweight with neck-flexing acceleration, a capable chassis for a US product and "don't meddle with me" styling to set it apart from its lesser sisters. Given its incredible performance its left-hand drive is an instant disadvantage on Britain's congested roads. I found myself constantly peering round the rear ends of articulated lorries to get a clear overtaking sightline - not a recipe for safe progress in a car as fast as the CTS-V.The heart of the V-Series is a 5.7-litre LS6 engine, a traditional American 90-degree V8 with two pushrod-activated overhead valves per cylinder and a close cousin of the six-litre unit which powers the Corvette C6 (see road test). This powerhouse is old-tech by European standards, but Cadillac is moving into the 21st century and uses alloy construction with fuel delivery via computer-controlled sequential injection and a compression ratio hiked to 10.5:1.In V-Series guise it adds up to 400bhp at 6000rpm and a mountain of torque peaking at 4800rpm with 393lb/ft of super elastic. That means electrifying performance, formidable acceleration and a glorious exhaust snarl.The key to any car in this sector is getting power down to the road effectively. Cadillac's answer is to pass it through a Tremec T56 six-speed manual gearbox. It manages well enough but the changes are heavy and the clutch felt like a bad-tempered Rottweiler snapping at my ankles as I explored the V's 4.7-second 0-62mph acceleration. It makes for tiring driving and that's not good news on a car which is capable of 163mph.Suspension has never been an American strong point. The majority of US cars wallow through corners like a wobbly blancmange - even the better ones. But not the V. The car's ride is hard, but well controlled. Double wishbone front geometry and a multi-link rear set up is hardly breaking new ground, but it works well and keeps the saloon in check while its processing manic levels of power and torque.It was only under extreme provocation and lot of revs that I found the rear end offering to step out of line. The standard selectable StabiliTrak traction and stability control system worked well.Cadillac's engineers have done a good job on the chassis and it has brakes to match with excellent stopping power from the Brembo ventilated discs and four-piston calipers. Grip was good on the test car's 18" Goodyear Eagle F1 245/45 WR18 tyres which held on well and failed to deliver the near obligatory squeal every American car appears to have on TV!There's a fair degree of beefing-up all round the CTS-V. The engine space has a cross-brace to stiffen the front end and there's substantial extra sound-proofing to maintain some semblance of refinement in the cabin without robbing too much of the fantastic V8 exhaust orchestration.Styling is aggressive to match its brutal performance. Seven-spoke flangeless alloys, wire-mesh grilles, deep bib spoiler and curtain rear and side skirts help create bad boy looks while inside the standard CTS wood trim is replaced with a satin chrome finish.The interior is comfortable - the leather-covered sports seats offered more support than on any other American car I have driven, but there's still a tacky feel about the dash. Instrumentation is OK but the rest is a mish-mash of cheap looking dials and switches with poorly-fitting plastics spoiling an otherwise impressive performance package.Cadillac still can't make a super saloon to the European standards set by BMW's M5, Audi's S4 or the Mercedes-AMG offerings, but it's catching up. Good though it is, however, the mighty V is simply too much of a handful for left-hand drive in this country. If Cadillac put the steering wheel on the right side for Britain, the CTS-V would sell. As it is, the car is going to remain something of an oddity over here.