Endurance Records

By the time the Mk 4 Zephyr/Zodiac models appeared, Cortina supremacy was widespread indeed in motor sport, and there was certainly no necessity to develop the latest big-car range at all in this respect. Whilst not therefore figuring prominenfly at all as a competition car, the Mk 4 did nevertheless have its moments, and in fact within a month of its introduction was driven into the record books.
In conjunction with Castrol, who were looking for a spectacular debut for their new 'Liquid Tungsten' motor oil, Ford embarked upon an attempt to set new FIA International speed and endurance records for cars with an engine of up to 3,000cc, in which class the present records were held by Austin-Healey (97mph over four days) and Citroen with an average speed of 86mph for seven days The venue was to be Monza's banked 2.65-mile oval track, and the target for the Zodiac was to achieve a 100mph average over a full week.

Modifications were allowed under the rules for these attempts, which were open to any types of car, including single-seaters, and therefore several changes were made to the Zodiac which it was hoped would guarantee success.
The porting in the cylinder heads was improved, in conjunction with new free-flow manifolds and exhaust system, but the carburation remained the model's standard Weber, and the bowl-in-piston combustion chambers were unchanged.
Specially hardened valves were fitted in order to reduce the possibility of valves burning out at sustained full throttle over many hours, but otherwise the engine remained standard from the mechanical point of view, although it was without a cooling fan.
In conjunction with the normal four-speed gearbox, a special rear axle assembly of 3.1:1 ratio, with the standard tyre rolling-radius, gave 24mph/ 1,000rpm without the complication of an overdrive. The tyres however did pose a problem. The standard 6.70 x 13 cross-ply type could not really be relied upon to withstand a sustained 100mph-plus over several hours, particularly on the rough Monza track which bad a reputation for destroying tyres, not to mention breaking suspension systems. The available 13in radials were all of much too small rolling radius, but after having been asked to help at short notice Goodyear came up with a special high-profile radial tyre suitable for the Ford 41/2in-wide rim. A set of heavy-duty export road springs were also filled.

Whilst the bodywork remained standard, a useful aid to streamlining was complete underbody plating enclosing the mechanicals. Changes inside the car involved removing all seating but the driver's, with a 40-gallon fuel tank residing transversely in the rear compartment and stowage space alongside the driver for spare parts and service items, as any parts required throughout the attempt, including the tools, had to be carried inside the car.

Major assemblies such as the engine, transmission and suspension units cannot be changed on these record attempts, so mechanical reliability is essential. With 40 gallons on board, plus well-filled tool boxes and numerous spares, the Zodiac was weighing-in substantially heavier than normal, but with its increased tune and underbody streamlining was able to build up to well over 100mph.
Practice sessions the week before the attempt determined fuel consumption rates and realistic lap times, and also, thanks to the car being equipped with much additional instrumentation, showed up an alarming tendency for the gearbox and axle oils to overheat. This was due to the underbody shroud, and so it was now partly cut away in the vicinity of the gearbox and final drive to ensure adequate cooling of these parts.
Suspension damage occurred too, largely due to a ridge several inches high where one of the concrete sections had become badly misplaced. This in fact had to be broken up by some of the Ford crew before the attempt proper began, but even then the Monza circuit remained like 'a permanent special stage' according to driver Eric Jackson.

In addition to Jackson were drivers Ken Chambers, John Bekaert, John Maclay and Michael Bowler, who drove in shifts on a three hours on twelve hours off basis.
Watched anxiously by the small team of mechanics, amongst whom was present-day Ford Press Garage Manager, Lionel Sangster, Zodiac OWC 500D began its attempt at midday, Saturday, May 7.
All went well until 11 o'clock on Sunday morning when gloom descended over the watching crew as the Zodiac came to a stand out on the track. Fuel starvation was suspected, and this could perhaps be easily rectified. But as the regulations stipulated that no assistance could be given whilst the car was on the track, there was the difficulty now of getting it back under its own, or the driver's steam for it was that individual alone who was permitted by the rules to push the car.

Solving this problem resulted in the curious sight of a dozen or so helpers in line astern apparently pushing each other, with only the leader, the driver, actually pushing the car! They need not have bothered however, as the trouble lay in the standard carburettor settings which were too lean for the modified car's maximum speed, and the overheating in the combustion chambers caused by the weak mixture had resulted in a melted piston. That record attempt was all over. But there was nothing which barred starting the whole seven-day attempt again - and there was a company hack Zodiac in the pits, with a perfectly healthy engine.

It took Ford mechanics Lionel Sangster, Alf Belson, Dudley Moore and Ernie Pittock, and Castrol's Ron Stacey, less than six hours to get OWC 500D going again with a 'new' engine built up from the two.
The block, pistons, connecting rods and crankshaft of the hack engine were used, with new crankshaft bearings. Married to this assembly were the cylinder heads, valve gear, manifolding and fuel system from the damaged engine, the carburettor now fitted with appreciably richer jets.

There was time for some initial running-in, followed by a complete service, before the record attempt started all over again at precisely midnight when John Bekaert embarked upon the first three-hour stint.
It was all systems go, with the Zodiac soon settling down to a consistent 106mph lap speed and the whole operation getting into the planned routine. Pit stops occupied little time as everyone swung into action. It took only 12 seconds to replenish the 40-gallon fuel tank by simple gravity feed from a large overhead drum arrangement; there was a filler neck on each side of the car, both of which were opened for the refill, with one taking the nozzle whilst the other instantly discharged the large quantity of displaced air. Other routine checks were carried out under the bonnet, and such was the glow from the almost white-hot exhaust manifolds that no underbonnet lighting was needed when checking the car during the hours of darkness. Changing the spark plugs, which on the V6 are right alongside these manifolds, was a tricky job under these conditions: 'It was one job I wished I hadn't drawn,' remembers Lionel Sangster.

The old records started to fall as the Zodiac began replacing them with altogether more impressive figures: 15,000 kms at 105.27mph; 10,000mls at 105.36mph; and 4 days at 105.31mph. But there was anxiety now: the ridged surface construction of the Monza track was taking its toll on the tyres which already had the quite formidable job of coping with over 11/2 tons of laden Zodiac at a constant 100mph or more.
Tyre wear was rapid, and with a small number having to be discarded early due to chunking, the stock of 36 of these special covers was dwindling faster than had been anticipated. Quick response by Goodyear with more tyres however alleviated the problem.
It was the front outside which took the worst hammering of all, with three tyres here losing pieces of their tread; but none of these deflated, nor did a fourth tyre which later lost the whole of its tread whilst on the rear, and this speaks volumes for the soundness of their carcass construction. A broken rear spring was the only other casualty, but it had little adverse effect on the car and was left in position.
With the V6 engine never missing a beat, the record for 20,000 kms was taken at 104.73mph, and that for five days at an almost identical speed of 104.72mph.
There was a problem ahead now not connected with the car itself at all: Ford had originally booked the track for the week finishing on the Saturday which would have been the final day of the originally planned attempt. Now it would be needed until midnight Sunday, but someone else had already booked it for that day. Delicate negotiations quite literally 'saved the day', and so the white Zodiac pounded on into the early hours of Sunday morning, by this time having added the 15,000mls and six-days records to its growing total, both at an average of 104.43mph.

Speed could now be eased a little, as only 95mph or so over the final day would be sufficient to keep both the 25,000kms and seven-day averages comfortably over the three-figure mark. The 25,000kms record was in fact taken at 104.12mph, and when midnight came the Zodiac had completed the seven days at an overall 103.04mph and had covered 17,311 miles. Petrol had been consumed at the rate of 11mpg, whilst consumption of Castrol' s new oil had been a modest 1,000 miles plus per pint.

All that had been attempted - nine world records - had been achieved, and all at over 100mph. Total success, and none were more jubilant than those five mechanics whose astonishing makeshift engine had enabled an outstanding victory to be snatched from the very jaws of defeat.

Ford didn't disregard the Mk 4 completely in respect of direct competition work, and one unlikely branch of motor sport in which a works Zodiac proved to be competitive was rallycross, where a subtly modified example gave some remarkable displays in the hands of the versatile Barry Lee.
Estate car springs were fitted to this saloon, and at the front were a pair of MacPherson struts specially uprated by Armstrongs. A stiffer anti-roll bar was used, this being of appreciably greater diameter than the original but ground down to standard thickness around the middle of its centre portion.
Slightly longer, fabricated track control arms were used in conjunction with a slight negative camber angle adopted for the front wheels. The front-end bodywork was also stiffened with additional welding of the flitch plates and crossmembers, whilst engine movement was restricted by modified mounts.
At the rear were larger bushes at the wishbone's swinging link attachment point, and geometry which now included appreciable rear wheel toe-in in the static condition, and greater negative camber, with the latter angle being calculated to eliminate any of the tuck-under which sometimes afflicted the standard cars.

Although seemingly extensive in number these changes were in no way fundamental, but rather refinements for specific use, and were to prove sufficient to make this Zodiac handle in a manner quite appropriate to a competition saloon.
It remained, of course, a very large and heavy car, but proved agile enough for Barry Lee to put up some creditable rallycross displays, often in the thick of it with the nimbler smaller models.
An outright victory was gained in one autocross event, and Barry also took the Zodiac through a series of driving tests to take first prize at a Plessey Auto Club meeting.

Although it would perhaps have been unreasonable to expect the Mk 4 to gain any top-level rally awards, in an effort to boost the model's image somewhat the Zodiac did make a couple of international rally appearances, the first of these being the Three Cities Rally (Munich-Vienna-Budapest) in 1969.
Prepared to Group 2 standards, and driven by Roger Clark of Ford Cortina and Escort fame, the Zodiac finished 16th overall and won its class on this event.

The other entry was in the 1970 Monte Carlo Rally on which Eric Jackson took a virtually standard Zodiac. Unfortunately, time was lost on the Continent due to ice in the fuel system after having taken on some water-contaminated petrol, and this spoilt any chances the car might have had of finishing highly-placed in its class.
It was perhaps a rather downbeat end for the international competition career of the big British Fords, but nothing could detract from those remarkable performances in the earlier years.