When the head of Mercedes-Benz design tells you that the company's next sportscar will be 'the most beautiful Mercedes' his team has ever created, you pay attention.And when the head of Mercedes-Benz AMG - the skunkworks division responsible for building the company's next sportscar - tells you its new engine will be a sophisticated masterpiece, you stop what you're doing and listen.Yes, ladies and gentlemen, the upcoming Mercedes-Benz AMG GT - that's the new sportscar to sit below the outgoing SLS and rival Porsche's 911 - is on its way. And, after some exclusive chats with the men behind it, we're quite excited.At the Geneva Motor Show, we asked AMG chief Tobias Moers whether the new GT - codenamed the C190 - will come, as rumoured, with a 4.0-litre, twin-turbocharged V8 engine. Moers replied\: 'No, that's not that wrong.' Which we're taking as a yes.The GT also definitely, definitely won't come with a manual either, Tobias making a hand gesture to suggest stirring a manual is unnecessary. 'Even the new Porsche GT3 isn't a manual,' he says. Nor will the GT come with AMG's four-wheel-drive system. Ever.On the subject of turbochargers, however, Tobias was clear. 'It's necessary now for us because you don't get that compromise between fuel efficiency and power output. Supercharging is, thermodynamically, not very good, because the power output into the supercharger is too high.'The thing is, everybody at AMG loves the big, naturally aspirated 6.2-litre V8, but trust us, the new V8 in the new sportscar will have excellent throttle response. Everybody will be happy.'The GT also marks the end of big, naturally aspirated engines for Mercedes AMG full stop, because - barring the SLK 55 AMG's free breather - the rest of the range is all turbocharged. The SLS? Every last model is sold out, and it's now been killed. Tobias admits that the death of the current SLS does leave space later down the line for another big supercar, though not anytime soon. 'Another SLS? It was only ever supposed to have a three-year life cycle, end of story, so we'll see another one later rather than sooner. I think the SLS should stand on its own now for about five or six years maybe, we haven't decided anything just yet.'The SLS' engine is also only a last hurrah in the C63 AMG too, but, Tobias confirmed that 'yes, that [new V8] engine could be a possibility for our new C63. It will be very competitive'.Competitive, yes, but on the subject of competitors, although engineers on the new Honda NSX took out every likely rival to see where the market was at, Tobias isn't so sure that's the AMG way.'For sure, we have some 911s - a Turbo and two standard cars - as well as a Jaguar F-Type, a Corvette... we've got all the competitors. But that's the big difference between the Japanese methodology and ours. They can do it better than we, because we've tried it in the past and it didn't work for us.'I think the new NSX will be a really good car, and we know how the Porsche handles, how the Vette handles - how our competitors handle. But what we try and do is have fun with our cars. And in the past, it's worked that if we are happy with our package, our customers are happy.' Anyone familiar with the Black Series SLS can attest to that.Speaking of which, there will be a Black Series AMG GT, too, 'along with many, many more variants,' Tobias said. 'The new sportscar which is in a new segment - price wise it's lower than the SLS - gives us a lot of room for spreading the portfolio out. A much wider range of models.'A wider range with very distinct lines, too, according to chief designer Gordon Wagener. 'The new sportscar will not necessarily have the same features as the Vision GT [that we saw at the LA show last year - the car built for Gran Turismo 6] but it will definitely have a similar language. The essence of that car you will see on a future sportscar.' We ask whether the GT will be a gullwing too. Wagener laughs. 'I cannot tell you that.''I think in each and every sportscar we do, there will be an element of our racing heritage. Every Mercedes sportscar is like a Silver Arrow, and the next one coming is maybe the most beautiful, maybe other than the 300, that we have ever done.'But - I was misquoted last time. What I actually meant when I said the AMG GT will be the most beautiful car we have ever done, is that it's the most beautiful car we - that's my team and me - have ever designed.'So how close to finished is it? 'It's done,' Gordon smiles. 'The design of that car is finished.'We'll see the Mercedes AMG GT before the year is out, and it'll be on the market by next year. And we can't wait.