
FFF 100 | GKN’s Four-Wheel-Drive Titan
On a rainy day in September 1972, GKN’s Hemi-powered four-wheel-drive FFF 100 created an astounding new world record, when the car accelerated from a standing start, up to 100 mph, and back to rest in just 12.2. seconds – and that was in the rain. An incredible 8 seconds less than the world record at that time, and a record that would remain unbroken until 2004. The Museum looks back at GKN’s monster named the FFF 100.
FFF 100 | Birch’s formidable concept
The GKN company had long been associated with the motor industry, supplying a range of specialised products including simple necessities such as nuts and bolts. The company’s managing director, Claude Birch, had purchased a four-wheel-drive Jensen FF direct from Jensen Motors, and was extremely impressed with its technology.
In 1971, the same year that the FF would be discontinued, Claude Birch came up with a concept of producing a one off experimental car based on the Jensen FF. The new car would be fitted with the powerful Chrysler 426 ‘Hemi’ engine.

The original concept drawing for the FFF 100 by William Towns. Perhaps it wasn’t a coincidence that the FFF 100 had similarities in design with the Jensen ‘F’ Type – also designed by Towns.
The project car was to be named the FFF 100, and the idea behind it’s concept was to build a car to full race specification, and to use the road holding and braking abilities of the Ferguson four-wheel-drive system and Maxaret anti-lock braking.

William Towns

Harry Grylls
The finished car would be used to test the performance and durability of some of GKN’s specialised components.
Additionally, the car would also be an excellent advertisement for GKN.
It had been an unfortunate fact, that GKN was perceived by many simply as a supplier of nuts and bolts.
It was Claude Birch’s aim that the FFF 100 would put across to the motoring industry world-wide, that the company produced a whole lot more than nuts and bolts.
The FFF 100 project was put in the hands of three specialists, Keith Hamilton-Smith from FF Developments who would be responsible for the chassis and mechanics; William Towns, who would design the body shell; and Harry Grylls, who had been the former Technical Director for Rolls Royce.
Although Grylls was now retired he agreed to be brought into the project as the overall adviser and co-ordinator.
Both Keith Hamilton-Smith and William Towns had associations with Jensen Motors, in fact Towns himself purchased an FF from Jensen Motors in May 1971.
As would be expected, Birch concluded the FFF 100 should be painted in the Company’s house colours of blue and white.
FFF 100 | Building starts
With drawings and detailing finished it was time for the FFF 100 to be made, Jensen Motors sold GKN an FF chassis, which was especially stiffened. The overall weight of the FFF 100 would be lighter than the Jensen FF, so softer springs were fitted to the front suspension, and less spring leaves were used to the rear to give the correct ride height.

The FWD transfer case, along with Maxaret unit. The system was a slightly upgraded version of the same unit used for the Jensen FF production cars.

The suspension of the FFF 100. Pretty much stock Jensen FF.
Ventilated disc brakes were fitted along with special hubs, which allowed the fitting of the fat Kent Alloy aluminium wheels. A modified Adwest steering rack was used, with the power assistance having been removed to allow more ‘feel’.
The Chrysler 426 ‘Hemi’ engine was modified by Keith Black, Chrysler’s own West Coast man. An A990 drag racing engine with dry sump lubrication formed the basis of the engine.
Internals consisted of NASCAR TRW pistons, solid lifter tappets and an STX 24 camshaft. The compression ratio came out at 11.5:1 and the finished engine with twin Holley carburettors to modified ports was capable of producing 600bhp.

The FFF 100 engine-bay. Outside of the main Hemi engine, many of the ancillaries were the same as used on the Jensen.

The Chrysler ‘426’ Hemi engine. Huge shrouded fans up by the radiator try and keep the immense engine-bay heat down.

Brake system was stock Jensen FF. The Maxaret solenoid can be seen to the lower right of the image.

Twin Holley carburettors fitted to modified ports.

A complex multi branch exhaust system was required. This image is taken from underneath the car looking towards the passenger-side. The front propshaft can be seen running through with the reinforced knuckle to the extreme right of the image.
Typically such an engine required a special multi-branch exhaust and a complex lubrication system using a March Formula 1 tank in the boot and a fabricated oil pan with triple gear pump.
To cool this immense engine a NASCAR type aluminium cross-flow radiator with twin thermostatically controlled fans were fitted. A road race version of Chrysler’s Torqueflite automatic gearbox was built by B & M Automotive Products and then the Ferguson four-wheel-drive unit was fitted to it.
By June 1972 the completed rolling chassis was ready for the fitting of the body shell.
The pleasing shell design by Towns incorporated two vents each side on the front wings, which reminisced with the famous two vents on the Jensen FF. The body was to be manufactured and fitted by the specialist company ‘Dimension Four’, headed by Tony Kirkaldy.
Glass fibre panels were pinned and bonded to a steel frame and the lightweight bonnet would be attached to the car by racing style clips allowing for quick removal. The car was painted in the Company’s colours of blue and white. The white paint was an unusual special matt preparation. There would be no opening windows and ventilation would be achieved through the Jensen supplied eyeball system.

Much of the interior was supplied by Jensen Motors. The dashboard was stock Jensen, but the passenger side cubby was removed as a further bank of gauge’s was needed.
Much of the interior was purchased direct from Jensen Motors including the dashboard, which was MK.III Interceptor. Blue leather was used for the interior, although the Recaro styled seats had blue coloured cloth inset sections.

Fire extinguisher close to hand. Standard Jensen seats were replaced with Recaros. Simple door panels were made specifically for the FFF 100.

Close-up showing the stock Jensen steering wheel. A special purpose rev counter was installed. The switch next to the windscreen wiper switch is a manual over-ride for the fans. Mopar expert, Duncan Watts, believes the amber light will be a shift light which glares at the driver at preset rpm and says shift gear now.

Close-up photograph showing the rear of the FFF 100, and the special ‘GKN-FF’ badge.
FFF 100 | Time to win records

Dennis Priddle
FFF 100 was finally completed by late summer / early Autumn 1972, and was ready to go out and get some records.
In September 1972 FFF 100 was taken down to the Motor Industry Research Association’s (MIRA) proving ground for the cars initial testing. Ironically it was raining by the time the GKN boys arrived at MIRA with the FFF 100 on a trailer.
There was quite a group that had come down to the track, including drivers, mechanics, and obviously, some of the brains behind the project.
According to Keith Lee, author, The Story Of The Drag Racing Legend, Dennis Priddle, there was three or four drivers on call that day.
Priddle was a drag racing legend (as the book title suggests), but probably the most famous driver on call was Graham Hill. However, it was Priddle that made the world record.

The FFF100 about to be removed from the trailer.

GKN staff in discussion. Claude Birch stands third from right. This is one of a number of photographs given to Jensen historian, Keith Anderson, by Claude Birch’s daughter.The driver that set the world record, Dennis Priddle, is the man in the blue jacket with white stripe to his sleeve (extreme left of the photograph).

Bonnet off and last minute checks.

Bonnet back in place, and last checks in preparation for the event.

A moody image captures GKN’s Titan before testing. It is actually one of the few images that shows the bonnet’s separated centre panel. This panel, which was painted GKN blue, is raised from the main bonnet to allow the two huge carburettors to stand proud of the bonnet line. It would seem by studying photographs, that this panel could be slightly raised or lowered if desired.

The FFF 100 off trailer and a short discussion before testing. Claude Birch standing by the car, talking to one of his colleagues.

Ready for records. Dennis Priddle behind the driving seat, and Birch in the passenger seat, going through things with him.
Everyone was left in no doubt that this would test the four- wheel-drive system to its maximum, especially with the 600bhp engine.
The standing record at the proving ground for ‘0 – 100 mph – 0’, in other words to accelerate from a standing start to 100mph and then immediately back to rest, stood at 19.2 seconds. That record had been achieved in the dry.
Having been manipulated off the trailer, the FFF 100 was allowed to warm up in readiness for the track. When everything was ready, Priddle launched the FFF 100 off from its standing start, with the car kicking up a spray of rain from the wheels.

The FFF 100 picking up speed.

This image captures the initial weather, wet with spray coming off the wheels.
The car accelerated without any wheel spin, quickly reaching the magic 100mph, and then immediately braked to rest. An incredible new record was set at 12.2 seconds, seven seconds faster than the old dry run record… and this was in the rain.
Later when the track had dried, FFF 100 was re-tested and achieved a staggering time of 11.5 seconds. There was no doubt left in anyone’s mind about the virtues of four-wheel-drive and anti-lock braking.

Further testing took place in the dry, knocking nearly a second off the car’s world record in the rain.
Claude Birch must have had a smile on his face that day to see this amazing outcome with his ‘pet project’. GKN were definitely set to claw back their development and production costs on the FFF 100, the GKN group as a whole would be taken very seriously by the motoring industry.
With initial testing over, FFF 100 was given back to Dimension Four, the Earls Court Motor Show was just three weeks away and GKN, via William Town’s modernist designing, had been asked to display the FFF 100 on the IBCAM styling stand. the FFF 100 was to be the centre piece of IBCAM’s display.
Dimension Four had the task of preparing the car in readiness for the show. The Motor Show went well and the FFF 100 caused quite a stir on the IBCAM stand, from both the motoring press, and the general public.

The FFF 100 on the IBCAM stand at the 1972 Earls court Motor Show.
After the Motor Show, the car was returned to the GKN FFF 100 team, where a few months were spent de-tuning the car for road use. A higher 3.07:1 axle was fitted and the stall speed of the torque converter reduced from 5000rpm to 3600rpm. The engine had a milder camshaft fitted along with hydraulic lifters.
Even in ‘softer’ road use form the FFF 100 was quite a tiger, capable of 0 – 60mph in just 4 seconds, 0 – 100mph in just 9 seconds, and could carve a route through ‘S’ bends at speeds well in excess of 100mph with absolute ease.
Unfortunately such power even in this ‘softer’ form, created heat and the generation of heat was colossal and sometimes difficult to control.
FFF 100 | Assault on the USA
By the beginning of 1973 FFF 100 was ready for its assault on the USA, once shipped across the car was immediately put to use at various exhibitions and test days, achieving the required publicity for GKN.
On one occasion FFF 100 was taken down to the Chrysler test facility in Michigan, the American engineers watched with disbelief as the car accelerated up to 120mph and back to rest…but with two wheels running on dry tarmac and the two offside wheels fighting through snow and slush.
Fame had been achieved both for the FFF 100 and for GKN, the car had served its purpose and was shipped back to England in late spring early summer 1973. Once back in England the FFF 100 spent a lot of its time stored at Dimension Four.
However, some further development work took place including the testing of Vandry non-lubricated bushes and a new GKN fuel injection system. Occasionally the FFF 100 was brought out of storage to take part in events such as the Shelsey Walsh, and Prescott Hill Climbs.
In fact, Pat Linda Neal, a member of the GKN staff, remember’s the Prescott Hill Climb, “the FFF 100 was also driven at Prescott, and stuffed in the bank by the owner of Ski yogurt who was a race driver. “
The Prescott day would be one of the last events before these sporadic outings stopped.

The FFF 100 about to do the hill climb at Shelsey Walsh. Photograph taken in the early to mid 1970s.

A side view of the FFF 100 taken at Shelsey Walsh.

Rear view of the FFF 100 taken at Shelsey Walsh.

The FFF 100 parked up at the Prescott Hill Climb. The photograph was taken by an amateur photographer in the middle 1970s. Probably one of the last events the FFF 100 participated in before being sold off by GKN.
With development taken as far as GKN needed to go, the FFF 100 just gathered dust in a corner of Dimension Four’s workshops, until eventually the car was sold off.
FFF 100 | Epilogue
In 2004, Autocar claimed a new world record for the 0-100-0 time. Breaking the 1972 FFF 100 record by a few points of a second in a Caterham R500 Evo. Their record didn’t last very long. Later that same year an Ultima GTR set a new world record at 10.31sec.
Today the FFF 100 remains a survivor, sitting in a UK-based private collection. GKN’s titan remains in a particularly original state, largely untouched since the 1970s.

The GKN FFF 100 photographed in 2009.

Side view of the FFF 100 photographed in 2009.

Interior view of the FFF 100 photographed in 2009.
FFF 100 | GKN’s Four-Wheel-Drive Titan
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ACKNOWLEDGEMENTS: Jensen historian, Keith Anderson | Felix Kistler, Secretary, Jensen Owners’ Club of Switzerland | Keith Lee, author, The Story Of Drag Racing Legend Dennis Priddle |Tony Marshall, former Sales Manager, Jensen Motors | John Page, former Service Manager, Jensen Motors | Mopar Expert, Duncan Watts.
COPYRIGHTS: The Jensen Museum
ADDITIONAL INFORMATION: If you have any additional information about this car, please contact us at archive@jensenmuseum.org or telephone on: +1694-781354
We hope you have enjoyed this feature.
If you would like notification of when new features are added to the Museum website, then why not subscribe.
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