The Jaguar name is 75 years old this year. In the Crystal Room, at the Mayfair Hotel in London's West End, the as-yet unknighted William Lyons revealed the first SS Jaguar on 21 September 1935. No longer was his Swallow Coachworks company just a coachbuilder which placed sleek, racy bodywork over humble Standard cars.

True, the SS initials – they stood for Standard Swallow – remained, to be dropped only after World War Two, by which time they had taken on other resonances. But Jaguar was now the brand name, the marque. And here were signalled the attributes that would serve Jaguar well for decades to come: rakish, seductive looks, upper-class cabin opulence, a strongly sporting impression and a surprisingly low price. That might sound like an advertising pitch, but it was true.

At that Mayfair event, intended to prevent Jaguar's debut from being swamped by the concurrent Olympia motor show, Lyons asked his guests to estimate the cost of the SS Jaguar 2½-litre saloon on show. The average guess was £632, so the news that it actually cost just £385 caused quite a stir. Its engine was still a Standard six-cylinder, but fitted with a new overhead-valve cylinder head to help it produce 102bhp.

Not shown at Mayfair, but simultaneously available, was a smaller Jaguar saloon. The 1½-litre had the same opulent, long-bonnet styling, complete with a metal-cased spare wheel on the nearside running-board, but it was slightly shrunken in every direction. The musculature was more meagre, too; it retained the sidevalve Standard four-cylinder engine, actually of 1608cc but producing a stifled 50bhp.

It's one of these Jaguars, just £285 new, that I am now inhabiting as we set off from the Coventry Museum of British Road Transport on Friday, 17 September 2010. The plan is to reprise that Mayfair Hotel dinner this evening, in the same Crystal Room, and arrive at the Goodwood Revival race meeting the next day. Our car (the white saloon, no.15) is the oldest, and the slowest, of the 75 Jaguars tackling the run to celebrate the anniversary, and a very different animal from the C-type, D-type and XKSS that head the racier end of the gathering.

Some cars come from Jaguar's own collection, but the majority – from pre-War SS100s and our car's bigger brothers, the 2½ and slightly later 3½-litre saloons to myriad E-types – are driven by their private owners. Post-War saloons of every description are represented: Marks V to 10 (the Roman numerals were ultimately dropped), the smaller Mk2 and its retrospectively termed Mk1 predecessor, plus XJs of all flavours. Jaguar's own PR lady is driving Austin Powers' Shaguar, an XK8 which appears to have been engulfed by a giant Union Flag, and she's finding a straight face hard to sustain.

Our saloon's custodian, David Brown, whose son-in-law's body shop beautified this white Jaguar, starts the drive as we're flagged away by the Mayor of Coventry. Its owner will join us at dinner, the genial Reverend Alex Aldous whose fleet of white-painted, senior Jaguars performs wedding-car duties. Truly an all-inclusive service.

Jaguar has lent each entrant a sat nav, but this seems quite wrong in a 73-year-old car. Besides which, the route it urges is very different from that in Jaguar's route book. But we don't jettison the 21st Century just yet, because it has one useful function: a speedometer. The Jaguar's own instrument expired en route to the start, to join the rev-counter in slumber. Nor is there a temperature gauge. We'd be flying blind without the electronic screen.

Still, there's plenty else to think about while driving the SS Jaguar. We're on the Fosse Way, and even this Roman road has acquired some bends over the years. I wanted to drive as early a Jaguar as possible on this event, preferably an obscure pre-War one largely overlooked in the classic-car press, and my wish has been granted with knobs on. I'm driving the SS right now, looking along the long bonnet to a Jaguar 'leaper' mascot of exquisite detail. The cat is leaping from a rock, and its bared teeth are extremely sharp.

This is one of the few sharp things about this car, because the reality of its dynamic demeanour is some way short of the visual promise. Admittedly, the sight of a flathead four-pot and a single Solex under the bonnet didn't conjure up too many thoughts of sweeping majestically through open, bucolic bends, but it's a fact that my 38bhp Saab two-stroke would leave this Jaguar for dead.

Never mind. It goes well downhill, which is when I wonder more strongly than I ever have before at the reasons behind Jaguar's refusal to adopt hydraulic brakes in the 1930s. (Contrast that with its pioneering adoption of disc brakes two decades later.) The hefty drums are still rod-operated, and 73 years of wear in the multiplicity of pivots means that the left front brake activates much more keenly than its opposite number.

This is excellent when slowing for a left-hand bend, but problematical at all other times. I must either brake gently and apply a large steering correction, or brake hard to allow the right to catch quickly up with the left. Call it the character of age; that the steering has a very large amount of play, not least because the wheel is loose on the column, builds the character yet further.

The engine, however, is doing its gentle best to haul over a ton of elderly Jaguar at a dignified pace. At one point on the frantically busy A34 we almost touch 60mph, and by the time we reach The Vineyard at Stockcross, near Newbury, for lunch, I'm quite attuned to the Jaguar's ways.

After lunch comes a wonderful run across the Berkshire Downs. A couple of hills force a downshift to second gear and cause a small tailback of cats with greater leaping ability, but the gearbox is co-operatively synchromeshed on its upper three gears and the clutch isn't always fierce. Now, with some wonderful open sweeps ahead, I can hone my cornering technique and keep us out of the ditches. It goes like this: turn steering wheel, take up the slack, feel the Jaguar immediately fall into roll-induced oversteer, unwind the steering a little, continue to take the corner in a similar sequence of bites until finally hauling the wheel straight again. It's a very engaging process, sufficiently so for us to pull out a surprising lead over the following XJ6 Series III.

Eventually rural idyll gives way to motorway and finally the unusually heavy traffic of London, disrupted for the day by the Pope's visit. Various E-types and tweaked-up XKs are suffering, temperature-gauge needles heading to the danger end, but we inch onwards in blissful ignorance with our thermometer dormant as myriad tourists photograph our now-scattered convoy. There's no steam, no smell, and the oil pressure is strong. All is surely well, and finally we reach our overnight parking place at the barracks by Buckingham Palace.

Dinner is served in the Crystal Room, archive films are shown, congratulations are proclaimed. This time there's no SS Jaguar 2½-litre and a picture has to do, but the point is made. Sir William would have been proud.

Next day, the Reverend takes command of his car and I squeeze into the back. Maybe people were smaller in 1937, but it's a very tight fit. I drift into a reverie of vintage-toned gear whines and the particular bump-motion of a car with two solid axles, lever-arm dampers and a flexible structure, before driving again through rural Sussex as we continue towards Goodwood. Alex Aldous takes his saloon into the Goodwood estate and the final approach to Jaguar's reserved area, and we've arrived at that incomparable pageant of motor sport history that is the Goodwood Revival.

Look! A Spitfire, a Hurricane and a Lancaster are flying over us, celebrating another anniversary: that of the Battle of Britain, 70 years ago. It's a moving moment for us because, unlike the 1937 Jaguar, we weren't there at the time. With a history like that, the SS Jaguar 1½-litre can be just as unhurried as it pleases.

Text: John Simister
Photos: Jaguar