Senna's stretched McLaren-Lamborghini: F1's greatest 'what-if?'

“Chrysler were keen to know how good their engine was, because it had been in the Larousse and various other things that hadn’t done very well at all, but Lamborghini were convinced it was good and had lots of horsepower.

“Martin Whitmarsh and Ron were sceptical of the numbers that Lamborghini were quoting [750bhp]. Martin went over to Italy to watch it on the dyno though and was suitably impressed with the numbers which he saw materialise.”

The engine had been designed by legendary Ferrari engineer Mauro Forghieri – at that point probably the single-biggest influence on the Scuderia’s success after its founder Enzo.

However, the Lamborghini unit hardly had rave reviews up to that point. Derek Warwick had become familiar with an earlier iteration during his Lotus stint in 1990, calling it “All noise and no go”.

Jeffreys was reporting to McLaren’s then design chief Neil Oatley, who also shared his memories of the McLambo with Motor Sport.

“It had potential,” he says, observing its performances in particular when used by the Forghieri-run Modena racing team, in the tentatively titled Lambo 291 car. “But it was very much an Italian engine run in an Italian team.

“It had shown some promise, but rarely maintained performance over an hour and a half on a Sunday afternoon.”

Forghieri and the head of Lamborghini’s F1 operations Daniele Audetto – who had been Ferrari team manager during the famous 1976 Lauda vs Hunt F1 season – were more confident of its reliability.

“I think that the [McLaren] relationship with Peugeot was already pretty well established in the summer of ’93,” says Jeffreys.

“So this [Lamborghini trial] was obviously not secret, but I’m sure that didn’t go down well with Peugeot, or maybe it was to keep them on their toes a little bit, if it was not necessarily a done deal.”

He explains how the team was well-equipped to produce a Macca mule to take on the Italian bull, but still had a challenge on its hands.

“We had made other ‘B’ cars: the MP4/3B in ’87 and MP4/4B in ’88, putting different engines in the back of what were essentially similar chassis was something we were well versed in.

“To install the obviously longer [and heavier, by 18kgs] engine, ‘stretching’ the ‘8’ occurred after the rear bulkhead.

“The monocoque was pretty well the same, but we had to change the engine mounts, the radiator installation, and get the front of the gearbox to match up with the stud pattern, [and] we tried to keep the side pods as much as we could from the Ford car.

“We had to increase the wheelbase by about 4.875″ to accommodate the engine, which meant a new floor and top of the radiator, but tried to keep the back end in a good position relative to the power unit – quite a lot of work was involved.

“Everything was so tightly packaged that if you change a major component like an engine, all of a sudden you’re hitting things which never used to be a problem – you have redesigned lots of interfaces as well as routes for water pipes and other things.”

“As it was intended just to be a test car, we didn’t increase the fuel tank size, so it wasn’t really a raceable option [as it was],” adds Oatley. “We did it in as simple a way as possible to try and evaluate potential advantages.”

The car took roughly two months to build, and had its first shakedown at Silverstone in September 1993, by Mika Häkkinen – who was immediately impressed.

“I’ll never forget the feeling of it around there,” he told F1 Racing in 2008. “It was amazing. The power kept on coming; we were really flying.”

After that quick Silverstone shakedown, the cars were packed up and taken overnight to Pembrey, where he and Senna got a day each running the car.

“Those first couple of tests went without major dramas really,” remembers Oatley. “Ayrton thought the engine was quite drivable, a little bit peaky on the power curve, but obviously felt quite a lot more powerful than the Ford engine.

“Pembrey is not a particularly fast circuit, so it’s not enough to get a feel for the characteristics of the engine.”

Senna is thought to have liaised with Forghieri in how to improve the engine, make more horses available at the lower end of the power curve therefore making it even more user friendly.

“[The following test at] Estoril was a bit more of an insight into how good it may have been [and there] it was very competitive,” says Oatley. “The power of the engine was just a huge step.”

At a final Silverstone test with Häkkinen, the Lambo did fall back into its old habits, exploding with such ferocity on the Hangar straight that it blew a hole in the floor of the car, but Senna was undeterred.

Having been able to truly stretch the legs in Portugal, the Brazilian was famously enamoured with the engine, and is believed to have made an impassioned phone call to Dennis urging him to utilise its extra horsepower.

“Ayrton thought we should just do it, run one car for the rest of the season,” says Oatley. “But Ron wasn’t really having that, obviously as it turned out we had a fairly successful last few races in 1993 anyway.

“In the first half of the season, we were running a standard valve spring Ford engine and only had the pneumatic valve unit from Hungary onwards – that made a fairly big step forward for us.”

Senna would win the final two races of the season powered by Ford, but ultimately signed for Williams Renault for 1994.

McLaren plumped for a works deal with Peugeot, not believing that Lamborghini had the development clout to go the distance, and hoping the French marque could transfer its recent Le Mans success to F1.

The ‘94 ‘Pug’ partnership turned out to be a disaster, both in terms of performance and reliability – Martin Brundle’s engine famously exploded on the grid at the team’s home Silverstone race, with McLaren and Peugeot splitting after one year.

“The Peugeot option wasn’t a great choice in the end,” says Oatley. “Not that we were inundated with proposals, but Mercedes came along the year after, and that was the kind of deal Ron wanted – a really focused manufacturer with a big budget to make it all work properly.”

And what was the likelihood of McLaren-Lamborghini ever having been successful?

“The Lamborghini project was very, very low-key and very underfunded in F1 terms,” he says. “Mercedes was going to be a better option long term.”

Like the Ferrari IndyCar and the Lotus Can-Am concept, the ‘McLambo’ remains one of racing’s greatest unfinished stories.