Down Mexico way

Michael Taylor drives the historic Panamerican rally in Mexico in a Mercedes SLS, with a posse of Federales.

What, we wondered, were two full tables of gun-laden Federales doing in our hotel's courtyard for breakfast in Puebla? The modern international view of Mexico is one of a country being torn apart by a war against rampant, ambitious drug lords, but was having our own armed guard at breakfast a bit over the top? Dressed sharply in dark blue uniforms, armed to the teeth with handguns, shotguns and stubby machine guns and swaggering full of swollen-chested menace, our Mexican protectors meant business. But what did that suggest we were in for?

The whole idea of coming to Mexico was to drive AMG's new SLS on the roads of the once-legendary Carrera Panamericana route that wound south from Puebla, about two hours out of Mexico City. It wasn't to get shot at. The Panamericana is said to be the world's longest highway, running from 30,000km or so from Alaska to Argentina, but we're interested in the part that runs around 3,000km through the Sierra Nevada mountain range, south from Mexico City down to the Pacific Ocean.

While the full route ran from the Guatemala border down to the coast, this is the part Karl Kling dominated more than 50 years ago in his original Mercedes-Benz 300 SL to win the Carrera Panamericana while many of his rivals died, torn apart in crumpling machinery hurled down mountain slopes that are still disdainful of modern efforts to tame them. The new SLS proved itself one of the surprises of 2009 when we first tested it in California, but the mountain roads there felt like heavily cambered ribbons of silk. Mexico's less-loved roads would provide the front-engined, rear-drive, famously gull-winged supercar a tougher challenge. And, if the police presence was any indication, there were other hazards to make that challenge even more difficult. But there were quick hints that we shouldn't have been so concerned. For starters, at the briefing, we were told that Mexicans famously drive quickly. And they don't get upset by people going quicker. Our Federales, we were told, wouldn't be concerned if we overtook them, as long as we kept an eye out for the monster speed bumps in the small villages.

Overtake them? That would prove more difficult than we thought. On the convoy out of the appalling Hotel Camino Real in Puebla (where a wedding party's band blasted out their celebration until 5am), they showed the first glimpse of their true colours.

Evidently, they were under instructions to suspend the road rules for us by practising their presidential convoy training, jumping from traffic light to traffic light and forcing other drivers to keep their less-expensive jalopies away from us as we worked our way out of Puebla's sprawl onto the four-lane highway south towards Oaxaca.

But it was in this start-stop traffic that we found the SLS's shortcoming. The full auto mode on its seven-speed, double-clutch transmission was just too shifty for anything more than a short run. So we switched to the paddle-shifted manual system, which is no great hardship when you don't have a clutch pedal to bother you, and slotted the Sport mode, just to provide a bigger audible bang for the aggrieved commuters.

Traffic snarls? Having your own Federales running interference is the motoring equivalent of a chartered Gulfstream, especially when ours have their intimidating dark Dodge Challengers cranked out to 200kph and are waving at us to pop and crackle down a couple of gears to sprint past them. But Mexico is a land of contrasts and the high-speed antics quickly gave way to thick, walking-pace traffic. That didn't concern our intrepid guides, though, because they used their anti-terrorist training to force other drivers off the road to let the SLS flotilla through. At one point, our nearest team of law officers physically steered in towards one lane hogger who quickly understood the point. With remarkable good cheer.

Yet for all this poverty, the Mexican people were cheerful and appreciative, with no hint of bitterness that we were driving a car of which its value would feed their families for life. As one explained when I let her son sit in the SLS for a photo, we could have gone to any country in the world but chose Mexico, and that made her proud, even if her chief concern was how much money we'd leave in the country, and ours was how much rubber.

We swing up and over the mountain range towards Oaxaca. And again, almost immediately, we find hard-core heaven. This is a road that forgives nothing and forgets everything. Responsible for more deaths here than Montezuma's Revenge, it's full of tightening radius corners with no guard rails, massive rocks on the apexes, sudden, dramatic changes in the grip levels and delivery drivers using whatever piece of road seemed handy, even if you were already there.

Yet, it just doesn't quite flow like the great ones, even if it never stops being a challenge. We grabbed the lead in the convoy until, coming to a stop to meander across one of the enormous speed bumps in a town, we were re-passed by our last victim - none other than AMG boss, Volker Mornhinveg himself. The man responsible for every last nut and bolt in the SLS, Mornhinveg erupted out of the village with his 6.2L V8 bellowing off the cliff faces, only to find ours warbling in synchronised harmony.

For more than 150km of the most devilish mountain pass you can imagine, Mornhinveg clipped every corner perfectly in his early-apexing style, squeezed the throttle beautifully out of corners and let his acclaimed supercar have its head. Lunch, in a ramshackle café in Huajuapan de Leon, involved quesadillas most Mexican restaurants only wish they could make. We left Herr Mornhinveg to its delights in an attempt to put some distance between us and the field to fully explore the SLS. Which we did, for about 30km, before the road flattened and got busy towards Oaxaca, where a city that looks like it hosts about 300,000 people actually has 10 times that.

But great roads come from the gods, and if the roads on the first day were challenging, the roads on the second day from Oaxaca to Huatulco, down on the Pacific coast, were stunning. Yes, we had five stops at Army drug checkpoints and, yes, one of them asked for a thousand Euros. But this road had everything you could possibly imagine, from light traffic, a changeable road surface, huge road cambers, awesome scenery, fast and slow corners, good vision through the a long series of bends and helpful locals.

Here, the road shines, the sun shines, the SLS shines - and there's almost 200km, running along the edge of the Sierra Nevadas, trying to get down the mountain to the coast and having to work its way around all of their folds and gullies, rises and quirks. It is, without doubt, one of the Top 10 driver's roads in the world. The SLS doesn't really need help with grip, but the road cambers on the wide roads can be up to four metres high, and so steep that you get driven down into the seat as well as across it, with the suspension crushing down and the ESP madly trying to figure it all out. Until we turned it off, then unleashed its full gristle unencumbered by electrical cushions.

Then the SLS braked straight and true, tipped in to tight corners with a wonderful, progressive adjustability and attacked the fast corners with comforting traces of understeer. Beautiful, just beautiful. It's a great car, this, and the Carrera Panamericana roads have handed to the world a great test of any car. Now, and 50 years ago.