90 years special: The history of Autocar’s road test procedures

The Autocar history of road test procedures

The Fifth Wheel fell out of favour, along with those trousers

Our methodology has changed, but the goal has remained the same: to measure and record all of the data that matters

The profile of a typical Autocar road tester has changed a great deal over nine decades – and in a way for which the current road test editor can only apologise.

There are currently no Le Mans-winning drivers or ex-Formula 1 competitors among our number. And editor-at-large Matt Prior’s ability to design high-output racing engines remains unproven – as far as we know.

For my part, barely a week goes by when I don’t expect the phone to ring offering a BTCC touring car drive in lieu of some poor unfortunate with an ingrowing toenail but, sadly, it never seems to happen. As any long-standing Autocar reader will doubtless have noticed, we are a shadow of the force of sheer brainpower, speed and ‘helmsmanship’ we once where. And I blame salary limitations.

I am, however, much less inclined to apologise for the many and various ways in which the devices and instruments of the Autocar road test have changed since 1928. While the approach, philosophy and aims of the road test remain very much the same today as ever, the nitty-gritty business of measuring and weighing, of strapping on equipment, of recording data and of speeding up, slowing down, climbing and cornering in the test cars to which we turn our attention has changed out of sight over the past 90 years.

It has done so out of necessity, of course, as the cars this magazine has intended to assess have changed – and our expectations of them have changed likewise. The road tester’s toolkit has also changed quite a bit, in ways we’ll get on to – and which, in the process of researching this article, have made me very grateful indeed (a nod to the editor for that).

If we had presented this week’s road test on the McLaren Senna in the same format as the first of two tests in our 13 April 1928 issue, on the Austin Seven Gordon England Sunshine Saloon and the Wolseley 12-32hp, here’s what you’d have got. Among 14 paragraphs published in total on the Austin, only four concerned driving impressions: the rest were mostly descriptions of the car’s layout, body, roof and interior, and of the practicalities pertinent to the refilling of engine oil and adjustment of the handbrake. Exciting, eh?

In the ‘data for the driver’ panel of empirical test results, meanwhile (the sort that would come to define the road tester’s job), the only numbers that appeared were of maximum speed and maximum acceleration in each of the car’s three gears (47mph flat out in top), its average fuel consumption (42.4mpg) and its stopping distance from 25mph 9a full 48 feet in this case).

That was, of course, because the road test of the day had bigger fish to fry. This was a time when getting to your destination at all could be stymied by your car’s mechanical frailty, its inability to climb or even to start in the first place, or the meekness of its brakes. And so we learned that the little Austin “would hold 21mph in second on a gradient of 1 in 10”, and that “in first gear, it held plenty in hand on a gradient of 1 in 4, even on a slippery and rutty surface”.

I reckon a McLaren Senna would “hold rather more in hand” on a steep hill. For the record, it’d probably climb a 1 in 4 gradient like an Exocet missile leaving a silo. Still, I can’t be sure, ‘cos that’s no longer a part of the test.

And what of equipment? Autocar’s road test pioneers needed nothing more than a stopwatch, a measuring wheel (for recording turning circle and stopping distance) and a pencil to log the data they needed for their work. They also worked in pairs out of necessity, rather than for reasons of consistency as we do today.

In-gear speed maxima were timed over a measured distance and the car’s instruments duly calibrated. And although the number of stopwatches a co-driver might simultaneously operate rapidly grew in order that several accelerative increments could be timed at once (a set of four watches wouldn’t have been unknown in pre-war testing), it was decades before other testing apparatus started to have an impact on the road testing process.

Fast-forward 20 years to post-war times and there was some extra empirical detail appearing in the Autocar road test. Road test number 1359, on the Lea-Francis Sports Two-Seater (9 July 1948), contained both in-gear and through-gear 0-60mph-style acceleration test results, as well as maxima in gear. Interestingly, mention is made of an “electric speedometer” used to measure true speed and calibrate indicated speed for accuracy. So it’s clear that, by this time, auxiliary testing equipment is being used to streamline the testing process and improve the accuracy of test results – although further details of what this equipment might have consisted of is tricky to find.

By the time we get into the 1960s, the collected test data of the Autocar road test has expanded to fill a full page, much as it does now – although the data itself is quite different from that which we record today.

The acceleration test results look familiar, but we also see the tractive effort (or longitudinal accelerative power) of a car’s engine being recorded via Tapley meter, fuel consumption being recorded at various steady cruising speeds using a flow meter inserted into the car’s fuel line, and more detail on braking performance than today’s Autocar readers might expect.

And so road test number 1760, on the Ford Galaxie saloon (5 February 1960), not only records the car’s stopping distance but also goes into some detail about exactly how quickly the car stops from 30mph when a load of 25lb is applied to the brake pedal (59 feet, in case you were wondering) …read more

Source:: Autocar

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