Concepts and prototypes : Lotus Etna (1984)

Lotus Etna front view

The Ital Design-styled, V8-powered Etna concept made its debut at the 1984 British Motor Show at Birmingham. It was based on the Lotus Esprit, added race-bred cutting-edge technology, and promised to be the UK’s first genuine mid-engined supercar. The Etna’s drag coefficient of 0.29 and Perspex upper body would have been enough in themselves to carry most other concepts to the front page back in 1984, but its sleek bodywork, penned by Giorgetto Giugiaro, was merely a glorious wrapper.

The press loved it. CAR Magazine screamed from its cover page: ‘The magnificent Giugiaro-designed Lotus V8 sets out to show the world that Hethel can build a world-beater. Buy it in 1988!’ The main feature did temper this enthusiasm slightly: ‘Such promise as this must be allowed to be fulfilled. Lotus, who so long ago graduated to the top of the tree as builders of the best Grand Prix cars, must be allowed to become makers of the world’s finest road car. With Giugiaro involved there is no question that they can do it.’

It was a similar situation to the beginning of the Esprit – the parallels were there to see, especially considering Giugiaro’s involvement. Lotus claimed it wasn’t going to make bold claims about a car so far from production, yet dropped hints about what the Etna was packing within. Lotus claimed that the Etna was to have computer-controlled active ride, with anti-dive, anti-roll and anti-squat. An adjustable height setting and self-levelling promised to make the drive consistent in all conditions. As for the rest of the electronics package, how about traction control, anti-lock brakes (still a supercar rarity in 1984), engine management, even active noise cancelling? The latter was a pet project within Lotus, even if it sounds like a flight of fancy now.

Lotus Etna styling sketch
Lotus Etna styling sketches: so similar to those produced by Ital Design for the DeLorean DMC-12

New V8 engine designed for the Etna

The Etna’s engine was very special, and far closer to production reality than the rest of the car. In 1978, Colin Chapman tasked Lotus Engineer Tony Rudd with turning the V8 engine that the company had been talking about into reality – he was given a budget, modest development resources, and told to make it produce 320bhp and 300lb ft. It was to be built on existing production lines, have as many parts in common as possible with the 16-valve slant-four already used in the Esprit, Elite and Eclat, and – most importantly – be a lean-burn design capable of exceeding US emissions regulations.

And that’s where fortune favoured Rudd. The slant-four Type 907 was an exceptional engine, once the bugs had been ironed out. It was light, powerful and economical, and taking a pair of them to form the basis of a new V8 seemed like the best way forward. Of course, a new block was designed, with careful consideration put into its cooling efficiency and stiffness and, although the double-overhead-camshaft heads were conceptually similar to the original four’s, they weren’t the same. Maximum power was quoted as 335bhp developed at a modest 6500rpm, although a maximum torque figure of 295lb ft at 5500rpm hinted at a peaky power delivery.

A great deal of work went into what became known as the Lotus DV8 engine – or Type 909 – but, like the Etna project itself, it was doomed. After the buzz at Birmingham, the Hethel offices went quiet, concentrating on the production of the Esprit and Excel, and trying to find a new partner to give it the financial security it so desperately needed to bring the Etna to life.

That was the backdrop to the Etna’s development: crisis. In the wake of Chapman’s death in 1982, Lotus was in turmoil. Sales remained low in the wake of the 1979 Iran-Iraq War and the subsequent hiking of fuel prices, which hit demand for all luxury cars. But the Etna had been pieced together on an extended Esprit backbone, built as a showpiece for the Type 909 engine and as a beacon of hope for the future.

What happened to the Etna?

General Motors bought Lotus in 1986 and the Etna and Type 909 were put on ice and eventually killed, as the company changed tack completely, working towards an inexpensive sports car that would eventually emerge in 1989 as the front-wheel-drive Elan. The spirit of the Etna lived on in Peter Stevens’ Esprit remix of 1987, but the emergence of a new Lotus V8 engine would have to wait until 1996 – and that was completely unrelated to the Type 909.

The motor show concept was placed in storage, to be sold at a Coys auction of a number of Lotus’s historic cars. Lotus specialist Paul Matty bought it and looked after it for a short while before selling it to (the now deceased) Olav Glasius, the-then chairman of Club Lotus Holland and owner of what was the world’s most important collection of the marque’s historic cars. The Etna prototype was in poor shape when it came into Olav’s possession, and he asked Ken and Neil Myers, the father-and-son Lotus restoration specialists based in Northampton, UK, to restore the car.

It was during this process, the Lotus 909 engine was discovered inside this static show car. And that meant the restoration became a project to make the Etna a runner.

Getting the V8 running reliably… for the first time

Neil Myers had a tall order. While the engine was in development originally, Lotus struggled to get it working reliably, finding that it was bending valves at high revs. In order to get the Etna running, Neil needed to cure a problem that Lotus never could. He said: ‘We found weaknesses on the nearside inlet cam, where the belt wrapped around just five teeth. We needed more wrap-around on that shaft, and we also needed more tensioning to fix the belt-jumping problem. That required a new crankshaft pulley, which we had machined locally. The project was turning into a real labour of love.’

Other problems in getting the engine running were fixed one by one, including the fitment of Land Rover Discovery engine management, and within ten weeks of arriving as a box of bits, it was ready to run. ‘I remember it so well, firing up the V8 for the first time,’ Neil says. ‘We ran it on a stand, with Olav listening on the phone. We were all so excited, but also knew that that there was still so much to do to turn this into a drivable car.’

Fitting the exhaust, driveshafts and fuel filler and tank was extremely time-consuming. With the majority of the car built from wood, clay and glassfibre, ensuring that things did not get hot was a major consideration. The other point of concern was where, and how, to mount things: the reservoirs for the brake and clutch cylinders are in the glovebox, while the radiator is mounted flat in the nose section. Rebuilding the Etna took Neil about 12 months, a remarkable achievement given its scope – and the fact that a running car has been made from a wood-and-clay styling model. It’s probably unique in Lotus’s history.

Lotus Etna (1984) rear view

Keith Adams
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5 Comments

  1. Lovely looking. Another great looking prototype that never made it into production, like the MG EXE and much later Jaguar C-X75

    • Beauty in the eye of the beholder ! Not for me, I’m afraid – it looks like a derivative of the Esprit without any of the flair

  2. The Etna does look rather bland, more interested in why the 4-litre Type 909 V8 features an unusual 70.3mm stroke and displacement of 4011cc instead of carrying over the stroke of the 2.0-2.2-litre Slant-Four engines.

    Can also understand Lotus’s desire to build their own Family of Slant-Four and V8 engines, yet wonder whether they would have been better off collaborating further with Vauxhall beyond using the Vauxhall iron blocks as test-beds for their new cylinder head while design of their own engine block was under way (since Vauxhall themselves also planned to develop its own Slant-Four based V8 engine).

    Fwiw the following below features an interesting image of the Lotus M80 project, which is basically an unbuilt 1970s proposed replacement for the Lotus Elan that was derived from the 1974 Lotus Elite.

    Considering the 14 year gap between the original Elan and the FWD Elan M100, Lotus would have probably benefited had they been in a position to bring the M80 into production to replace the original Elan and retain a presence in the small sportscar sector, which as was the case with the larger X180 / S4 Lotus Esprit rebodies would also allow for the possibility for the M80 to receive M90 and M100 style rebodies before finally being replaced by the Elise.

    https://www.wymondhamandattleboroughmercury.co.uk/news/not-a-nine-to-five-job-oliver-winterbottom-looks-back-on-a-life-of-car-design-at-lotus-and-jaguar-1-5036544

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