Driven Mad - 1969 Cosworth 4WD F1 Prototype

British engineering firm Cosworth was formed in 1958 by two former Lotus employees, Frank Costin and Keith Duckworth. The pair kept a strong relationship with their former employer, and slowly expanded their efforts from developing individual parts to the production of completely original racing engines. With the support of Lotus founder Colin Chapman, this venture lead to a long-standing relationship with American automotive giant Ford, which bought the rights to Cosworth’s FVA four cylinder engine in 1966.

Ford agreed to fund the design and development of a brand new V8 based on FVA architecture, which would be used in the recently revamped Formula One. For some unbeknown reason, the pinnacle of motorsport had been using tiny 1.5L engines since 1961. The Mickey Mouse motors barely passed the 200 horsepower mark, which lead to Formula One rapidly being overtaken by sportscars as the fastest racing cars on the planet. By 1966 this development was finally addressed, with the introduction of a new 3L formula.

From 1961-1965, puny 1.5L 4 cylinder engines like this Conventry Climax FPF were in widespread use.

From 1961-1965, puny 1.5L 4 cylinder engines like this Conventry Climax FPF were in widespread use.

The change had not been a smooth one, with many manufacturers caught off-guard. As a result most teams were forced to use enlarged versions of 1965’s engines, which often could not be stretched very far past the 2.0L mark. Amid this chaos, the Cosworth V8 project was looking to be a real opportunity for the company.

On June 4, 1967 this hunch was proven completely correct. Debuting in the revolutionary Lotus 49 as a stressed member, the DFV scored a win in its first race, the 1967 Dutch Grand Prix at Zandvoort. Realizing the engine’s world beating potential, Colin Chapman insisted it would remain exclusive to his Lotus team.

The legendary Cosworth DFV V8.

The legendary Cosworth DFV V8.

However, Ford of Britain representative Walter Hayes had noticed the same opportunities Chapman had, and feared Ford would endure damage to its image if Lotus would go out and curb-stomp the utterly helpless opposition. Making the engine widely available and leveling the playing field would be in the company’s best interest, as it would maintain a certain degree of neutrality.

With this in mind Colin Chapman was calmly told his supply of engines would no longer be exclusive to him, and the tremendous engine would become available for any and all teams that had the money. With this move Ford had democratized cheap, easy and reliable performance. Any old outfit with a fresh bank loan was now able to get a perfect plug-and-play engine and stick it to the big boys. For Cosworth, Ford’s decision was a godsend, as orders for the DFV went through the roof.

Jim Clark and the Lotus 49 giving the Cosworth DFV its debut, Zandvoort, 1967.

Jim Clark and the Lotus 49 giving the Cosworth DFV its debut, Zandvoort, 1967.

As more and more teams got their hands on the tasty new Cosworth product, a clear issue with the engine was starting to make itself clear. It was simply too good. Chassis, suspension and tire technology from the late 1960’s simply wasn’t up to the task of handling the vastly more powerful 3L unit.

As a result the elegant cigar-bodied machines of the time had become quite unstable and difficult to drive. Traction was now in short supply, and it needed to be found fast. F1’s brightest minds were faced with the challenge to contain and harness all those extra horses.

The early 3L cars were hard to handle.

The early 3L cars were hard to handle.

One key solution to the tire-shredding problems was four wheel drive. In the public eye, the technology was still considered to be reserved for tractors and military trucks, but those on the cutting egde of performance were starting to warm to it.

As early as 1961 a four wheel drive Formula One car appeared, the ground breaking Ferguson P99. Despite featuring an outdated front-engine layout and the four wheel drive system robbing much of the power from its meager 1.5L 4 cylinder, the car etched itself into the history books. In the very capable hands of Stirling Moss it won the non-championship International Gold Cup at Oulton Park in damp conditions.

Stirling Moss and the innovative Ferguson P99.

Stirling Moss and the innovative Ferguson P99.

With the performance of the Ferguson still fresh in their minds, Cosworth started an unprecedented project in late 1968. Rather than wait for the developments of their customer teams, they would try their hand at building their own complete Grand Prix car.

Cosworth had never attempted to design anything on this scale before. Even so, they realized the first team who’d get the new engines under control would be the one to rake in the race wins. Cosworth was confident they could beat their opposition by fielding the first 3L four wheel drive car.

Unfortunately the daring project was hit by a setback early on. While Cosworth’s designer Robin Herd and his team were working on the car, Formula One experienced another revolution. F1’s top designers had taken notice of the amazing work done by Jim Hall of Chaparral. Hall had incorporated wings in his Can Am designs, which he used to generate something he called downforce.

The engineering boffins in the world of Formula One quickly realized this principle could be incorporated to great effect in Grand Prix machinery. By fitting an upturned aircraft wing, air flowing over it would cause the car to be pressed down onto the tarmac, greatly increasing grip. This provided a cheaper and much lighter solution to the traction problem Cosworth was trying to solve. Back at Cosworth, the four wheel drive project had been put on the back burner. The car was banished to a small shed behind the main factory, affectionately called The Toyshop. It was here where one of the most unusual and innovative racing cars ever was born.

Ironically it was Lotus who introduced the wings at the 1968 Monaco Grand Prix.

Ironically it was Lotus who introduced the wings at the 1968 Monaco Grand Prix.

For obvious reasons, the firm’s main concern was the car’s intricate drivetrain. Unlike the agricultural Ferguson P99, the 4WD would feature a more competitive mid-engine layout. Traditionally the DFV engine was bolted directly to the chassis, with its gearbox mounted behind it.

The gearbox effectively functioned as the rear end of the car, and mounted the differential and suspension. To get drive to the front wheels, the team would have to construct an elaborate series of driveshafts and differentials, which would somehow have to bypass the engine.

The offset driving position is clearly visible here.

The offset driving position is clearly visible here.

Feeling the complexity and weight of that approach would render the intended performance gains null and void, Robin Herd pushed for a radically different solution. Instead of working around the engine, he decided simply mount it backwards. The clutch was now facing the driver’s seat.

The engine powered the rear axle through a short driveshaft, and sent its 430 horsepower to the front axle through a collection of three differentials and a series of driveshafts passing the driver on the right hand side. The driver had to be moved slightly to the left to make room for the complicated drive assembly. In the front a Limited Slip Differential was found, ensuring optimal traction at all times.

A sketch of the Cosworth's unique layout.

A sketch of the Cosworth's unique layout.

To counter the massive weight penalty caused by the intricate drivetrain, the car was constructed from an exotic super-light alloy known as magnesium. This posed a sizable safety risk, as magnesium was a highly volatile and flammable metal. Cosworth seemed to accept the dangers of using the material, as they also worked hard to produce a magnesium version of the DFV engine as well.

The end result looked like it came straight from outer space. In a bold break from tradition, the car featured angular, squared bodywork all around. Compared to the svelte rounded designs of the time, the Cosworth was a complete alien. In addition to its jagged nosecone and massive nostrils, the car featured a primitive version of the common sidepod. The four wheel drive system allowed for equally sized tires on all four corners, and equal suspension geometry as well. Hopeful of its potential, Cosworth started a testing regime in the spring of 1969.

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Once it was doing its laps, the 4WD revealed itself to be quite the disappointment. Predictably the problem was caused by an unruly drive system supplying irregular power to the front wheels. The team didn’t seem to be able to direct to engine power to where it needed to go.

As a result the car weaved all over the place, as one wheel would get more power than the other at different times. Eventually the culprit was found to be the front differential. The mechanical LSD would engage and disengage in completely unpredictable times, which caused the perilously unstable behavior of the 4WD.

The car's test drivers were rather displeased with its performance.

The car's test drivers were rather displeased with its performance.

With the problem identified, Cosworth modified the differential to disengage when the throttle was released. This would ensure a certain amount of stability, but the car’s handling problems were far from cured. As there were no other options left, Robin Herd turned to using a variant of the wings which had been rapidly gaining traction in the F1 field. To this end a rudimentary rear spoiler was fitted, and the nosecone morphed into a grotesque three-pronged affair.

The simple spoiler did wonders for the car’s handling. Reports from Cosworth test drivers became much more positive, and it seemed the project could be saved after all. After another series of tests, the car was entered into the 1969 British Grand Prix at Silverstone. Cosworth driver Trevor Taylor was selected to do the honors, but he and the car would never show up.

Having watched the progress of the 4WD project with wary eyes, Keith Duckworth finally decided to pull the plug. He realized the project was most likely doomed, and wanted to save the company from spending even more money on it. The car had already cost 130,000 GBP, which was a giant heap of money in 1969. As the financial cost of continuing to run the car was considered to great, the 4WD would never turn a wheel in anger.

The Cosworth 4WD was a bold and ambitious idea brought to life by a rising star in the world of motorsport. In the late 1960’s Cosworth could almost do no wrong it seemed, but building an entire car was a whole different ballgame. The company tried to outsmart and outgun the competition by designing the first purpose built four wheel drive machine for the 3L era, but was quickly out of its element.

As it turned out, building such a radical concept into a competitive racecar was not as simple as it seemed. With the aerodynamic revolution drawing question marks around the 4WD’s right to exist, and tens of thousands of pounds spent on the troublesome car, Keith Duckworth wisely terminated the project. One can only wonder what it could have accomplished.