Enough of the aesthetics, now the power beneath the bonnet

For two weeks, I lightly discussed the aesthetic aspects of skin-deep motor vehicle design.

More detailed explanations will follow at a later date, but for now let us look at the other important design factor; performance.

While looks, and ultimately the outright appeal of a car, tend to be subjective and rely heavily on individual tastes (and strength of eyesight), the physical capabilities fall under a more exact science and can thus be taken to be the universal truth.

Judging a car’s appearance is as simple as eyeballing it, so how is the performance of a car measured?

Acceleration is first, most commonly expressed in 0-100 km/h times, or 0-60 mph in medieval units of measurement.

Quarter mile runs, standing kilometre, half mile and full mile figures are also quoted, which also give an idea of how fast a car accelerates, as does the observed speed at the end of the given acceleration distance.

Braking is next, and the most typical statistics quoted are 100 km/h to 0, 200 km/h to 0 (the McLaren Mercedes SLR does this in less than 65 metres, similar to a Ford Focus at half that speed, and the McLaren’s is almost half the distance that a Ford Anglia takes to brake from half the McLaren’s speed).

For the Bugatti Veyron’s 400km/h to 0, you will have covered a good four football field-lengths by the time this happens. Both distance and time intervals are usually quoted.

Last up is the cornering grip, the ultimate holding power of the tyres-suspension-chassis-centre of gravity-steering geometry collusion point.

This is usually expressed in terms of centrifugal acceleration, better known as lateral g. 1g is the numerical equivalent of the earth’s gravitational field constant, determined by Isaac Newton to be steady at 9.81 m/s2 (metres per second per second, or metres per second squared).

Braking and acceleration are also sometimes expressed in g. But a lot of us fear mathematics and physics, and don’t particularly care for numbers and SI units, especially that last part.

There should be a way of giving a single parameter that neatly sums up all those numbers.

Only really obsessive buffs, like yours truly, derive any sort of pleasure reading numbers on a multi-column table and comparing them to more numbers on other multi-column tables, and it is for this exact reason that normal production cars are taken to race-tracks to try and establish a respectable lap time.

After all, the lap time of the car neatly sums up everything: acceleration on the straights, braking coming up to the corners and the cornering ability through the corner, all rolled into one.

To bring a semblance of order in this (there must be hundreds of thousands of racetracks around the world), and for the sake of uniformity, there are a few racetracks worldwide that have been accepted as the benchmark determinants of a motor vehicle’s capabilities, and the most famous, the most dangerous, the most demanding and the most fun to drive is found in the Eifel Mountains in Germany.

Die Nürburgring (The Nuerburgring): The Green Hell: Seventy kilometres south of Cologne and 120 kilometres northwest of Frankfurt sleeps the medieval village of Nurburg, and around this sleepy hamlet loops the world’s most famous racetrack: the Nuerburgring.

The track is an unnerving 20.8 kilometres long in its current public-accessible format. Over the years, the track has changed configurations, and is at the moment split into the 22.8 km Nordschleife (Northern loop) which we are concerned with, and a 7.7 km Südschleife (Southern loop), mostly used for circuit race events such as F1, though the Nordschleife is still also used for some events.

There is a very good reason this track bears the nickname “The Green Hell”, and not just because several racing drivers have come to their ends along it over the years. The place is unforgiving and very few mistakes, if any, go unpunished.

There is little run off, the corners (of which there are countless) and crests are blind, so getting your line wrong or setting your car up badly will not end well.

The issue is that it is also a high speed arena, so driving slowly will only get you rear-ended by ambitious Germans in hard-charging 911s. It is not a place for the inept or the weak at heart.

This is exactly why auto builders bring their new-fangled hardware here in search of glory. Even the drivers have to be carefully selected when cars are put to the test: the driver too has to go the distance, not just the car.

Driving at an average speed of 160 km/h through more than 100 hairpins, sweepers, S-curves and crests for almost 10 minutes is sure to put a lot of pressure on both man and machine.

To cap it all off, there is a 300 km/h long straight at the very end, where high horsepower cars can really show their mettle, but on days when the track is opened to the public, drivers are required to slow down here, rather than speed.

This is how the lap times are significant, again to both driver and car. If you drive an ordinary car (200hp or less, say) and crack 10 minutes, you could be a bit special behind the wheel.

Less than 9 minutes and you might need the 200hp, or a little more; or better yet, superhuman driving skills. Between 8 minutes and 8 and a half calls for some 250hp plus.

Anything less than 8 minutes, in any car, and you would be advised to quit your day job and seek employment as a factory driver for any of the major companies.

The most hard-core sports cars have their lap times ranging in the early 7 minutes, at the hands of professional drivers.

So far only three production cars have broken the 7 minute barrier, and even so, two of them are not really road legal (the Radical SR3 at 6:57, an open-top racer with a motorbike engine and the first to register a sub-7 minute lap time; the Ferrari 599 XX, and the Pagani Zonda R, at 6:47, which took the record recently).

The Top Gear Test track: A lot of you must be familiar with this place, if only from the on-screen television marvel that is the BBC Top Gear show and its housekeeper, The Stig.

But are you aware that it is another unofficial test arena for motor cars, and that most manufacturers keep a keen eye on how their vehicles perform here?

The Power Lap Board, as it is now famously known, has been a make-or-break feature for vehicles participating on the show, and is something that is actually taken quite seriously, notwithstanding the zoo-like antics of one Jeremy Clarkson (he sometimes sets fire to the strips of paper on which the car’s lap time is written).

It is hard to actually tell what the track looks exactly like just from watching; all we hear is “Chicago”, “Gambon”, “Hammerhead”, “Follow-through” and so on, but extraordinarily, the track layout is in a figure of 8, meaning it would be worse than useless for holding a race (someone had once suggested that they should hold a Formula 1 race there).

Fancy names aside, all those corners and straights did not just fall out of the sky into view of BBC TV cameras; they were all designed intentionally — by the Lotus Group no less, meisters of automobile handling and chassis setup.

The track is usually run anticlockwise for the first loop of the figure 8. The first corner is a left curve of reducing radius (also called Willson Bend, but this name is rarely used), coming after a high-speed left-right kink on the opening straight.

Next up is Chicago, a steady state circumventing a tyre wall. Steady state corners are those taken without steering correction (constant application of lock), and the motor vehicle’s angle of attack is adjusted either using the throttle or the brakes.

This bend was purposely built by Lotus to expose a chassis’ propensity for either oversteer or understeer.

After that comes Hammerhead, a tightish left-right switchback that tests chassis balance, braking and brake balance, and the effect of hard braking on a car (tramlining, yawing or locking wheels).

This bend also shows up understeering chasses on entry into the second bend (the right after the left), or oversteering chasses as you exit the whole thing.

From there comes a right sweep that feeds into the follow-through, where the vehicles are maxed out, shooting past the tyre wall (again) into a left sweeper called Bentley (another rarely used name) and in to the second-to-last corner as it has now been known, another hard left and regarded as the trickiest bend in the whole course. It is easy to spin out on this bend by oversteering.

If you don’t oversteer into the grass (or spin wildly) through the penultimate corner, then the final corner will definitely get you.

Called Gambon, this corner has been the undoing of several high ranking individuals up to and including, but not limited to The Stig himself (it was named Gambon after Sir Michael Gambon took it on two wheels in an earlier season of Top Gear).

Besides Sir Gambon, other persons of note taking that corner on two wheels include Hollywood actor Tom Cruise and a former Arsenal player.

From there it is on to the start/ finish line. All this covers 2.82 kilometres. The lap time of any given vehicle through that course goes onto a board, called The Power Lap Board.

There are rules governing that board, first being that only vehicles available on sale in the UK can have their times posted on it.

Other rules include street legality (the appearance of number plates and indicator lamps confirm this), the ability to go over a sleeping policeman (a flattish speed bump) and the use of street tyres.

This means cars that are too low at the front, or cars running on slicks are not allowed, as are limited production cars that are sold out.

This does not deter the team from timing anything they can get their hands on. Formula 1 cars have had their chance to shine there, and the lap record is held, not by a car, but by a fighter aircraft, the Sea Harrier jump jet, at 31 seconds.

Not being anything roadworthy (not a car, not street legal, and not using road tyres), its time cannot be posted.

Most cars, particularly the top ranking marques on this board, would not be instantly recognisable to a good number of you out there, so I will not dwell too much on the merit list, but a few key facts: the first Veyron slotted in fourth position first time it went round, and was further dethroned rapidly in succession by a Zonda F roadster and a Caterham R500.

The successive Super Sport took the honours, but has now been unseated by a V8-powered Ariel Atom 500 at 1 min 15.1 sec.

Ehra-Lessien: Pronounced “error le scene” (including accent and inflection), this is a top secret test facility that became famous because of the Bugatti Veyron.

It is not used by just anybody; exclusive rights of ownership, management and use belong to the giant Volkswagen Group, the same posse of excessively clever people who engineered the Veyron.

While it covers 96 kilometres of any imaginable tarmac track condition, the most spectacular stretch is the 8.8 kilometre long arrow-straight section.

So straight and so long is this section that it is possible to see the curvature of the Earth’s surface along it, and it is here that the two Bugattis (407 km/h Veyron and 431 km/h Veyron Super Sport) set their respective production car speed records.

The stretch is parenthesized by two banked corners, usually taken at 200 km/h for those planning on clocking 400 km/h along the straight. It is one of few places on Earth where this is possible.

Nobody sat down and decided that the Nuerburgring and the Top Gear test track would be the benchmark facilities for determining a vehicle’s physical abilities, it just happened.

It has come to be that any sports car manufacturer who wants to build a name for themselves brings their vehicle to the Nuerburgring and sets a lap time, which they would shout about if it beats that of their competition.

Nissan and Porsche got into a scandalous tiff when the R35 GT-R beat Porsche’s 911 Turbo, causing Carlos Ghosn (head honcho at Nissan) to brag endlessly and Porsche to throw a wobbly, accusing Nissan of dishonesty.

Nissan returned for the second time and posted an even better lap time, after which they bragged even harder (“The Legend Is Real”, so goes their YouTube video showing the Nissan conquering the ‘Ring).

Ferrari set a lap record with the 599 XX car, but their rivals Pagani showed them up a few short weeks later with the Zonda R, making Ferrari’s one of the shortest-lived lap records ever, and leaving Pagani as the current holders of the mantle.

Maybe we should build a track of our own here and get in on the action.

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