I can see now why there was a look of consternation on the face of the Nissan lady when I handed back the keys of the 370Z spluttering, "What the hell is this?" The car had inspired such strong feelings that expressing them loudly was easier than doing so accurately, and it took a few moments for her to realise that I had given the wrong impression.The thing is, the 370Z just isn't the car you would expect it to be. What you would expect it to be is (from looking at it) a shortened - Manx, if you like - version of the old 350Z with (from reading about it) a larger and more powerful engine. And that's kind of what it is, up to a point. But there's a lot more to it than that. Really there is.You will have your own opinion on this, but to me the application of a chainsaw, or whatever it was, to the Z's rump has turned it from a machine of some elegance into a brutal, almost ugly car. That would not have sat well with the 350, which was never really sporty almost regardless of what Nissan did to it, but the 370 loses no opportunity to inform you that it is a different car altogether.The new character is not just about the engine, though that has been enlarged by 0.2 litres in a process which also involved changing about 35% of the components, but about the gearbox, which clatters from one ratio to another and makes a significant whine, and the suspension, which could be described as giving what journalists used to call an "uncompromising" ride.Everything is more sudden, louder, more in-your-face than it was in the 350. The Grand Touring experience has given way to something far earthier. Driving the 350 was like going for a walk with an Afghan hound trotting alongside you on an elegant lead. Driving the 370 is like using both hands to grasp a stout chain in an attempt to control the pit bull terrier on the other end.Or so it seems. I'm aware that other journalists consider the 370 to be a lot friendlier than the 350, and I can see why they think that. You would never want to push a 350 too hard because it didn't really enjoy that sort of thing; the 370, in contrast, will take almost anything you can throw at it.Not only is it faster in a straight line (Nissan says that the official 0-62mph time of 5.3 seconds is "not optimum" and suggests, uniquely in my experience, that a good driver could do better in the right conditions); it will also respond much more willingly to being pushed through corners. Warning flashes from the traction control light make it clear that the full 326bhp can't entirely be dealt with by the back end, but you can still have a lot of fun as long as you don't overdo it with the throttle pedal.So the whole pit-bull-on-a-chain image describes how the car feels more than what it actually does. And I have to say I quite like this duality, which is odd for me because I usually prefer performance cars to be more subtle than this. Next thing you know, I'll be getting a tattoo.But what I like even better is the noise. On full throttle the roar of the engine fills the car and dominates your experience of it, and to be quite honest I've never heard anything of the kind before. It has some of the characteristic quality of a V6, but more generally it sings a very distinctive song which it would take me a very, very long time to tire of. Modern high-performance engines do not, on the whole, sound as thrilling as ones from years past, but this one is a soul-stirring exception.What I very much don't like is the almost complete impossibility of seeing where you are going when you are trying to reverse into a parking space. The level of visibility is ridiculous, and I blame it for taking three attempts to park within 20 degrees of the correct angle on one occasion (the two people who were standing watching very kindly walked away before I finally gave up, so I didn't have to face them afterwards).I don't have a word to say in favour of this nonsense, though I might grudgingly admit that it does seem appropriate for a car which forces you to put some effort into every other type of driving too.The 370Z creates such strong emotions that it seems dull to write about equipment levels, but I suppose I'd better. The test car was in GT Pack trim, which puts it in the middle of the range and means it has 19" alloy wheels, heated seats, an eight-speaker, 6-CD Bose sound system (for use in the unlikely event that you get fed up with the engine noise), cruise control, a speed limiter and Synchro Rev Control (for matching the speed of the engine to the gear you're going to select next), none of which is available as standard on the entry-level car.For a further £1700 you can have the GT Ultimate, which comes with suede leather upholstery and a DVD satellite navigation system with voice control which is also an option on the GT Pack. Also available at extra cost are self-repairing Scratch Shield paint and, for £1400, a seven-speed automatic gearbox, though anyone with two functional legs who chooses such a thing is surely missing the point of the 370Z. Engine 3696 cc, 6 cylinders Power 331 bhp @7000 rpm Torque 270 ib/ft @5200 rpm Transmission 6 speed manual Fuel/CO2 26.9 mpg / 249 g/km Acceleration 0-62mph: 5.3sec Top speed 155 mph Price From £30387.00 approx Details correct at publication date