Elan development

Nearly 10 years ago Lotus introduced a small sports car that looks as though it could go down in history as the last true sports car to be constructed along conventional front-engine-rear-drive lines, yet possesses superior performance and handling to any tuned saloon car alternative. Mr. Chapman and his team called it the Elan, and it was welcomed by many enthusiasts for features such as the light and rust-proof glass-fibre body and the famous independent suspension giving incredibly accurate handling, without the traditional spine-jarring ride of small British sports cars. It had other factors in its favour as well: terrific acceleration without the normal penalties of bulky sheet metal and fuel gobbling 6-, 8- or 12-cylinder engines, plus an easily tuned twin overhead camshaft engine that could be developed for even better road performance, with no fear of handling or braking deficiencies spoiling the job.

The car shown in our photographs represents a currently successful Elan Sprint derivative that uses a massively enlarged 2.0-litre twin-cam engine and Chevron B15 Formula Three front suspension. Driven by David Brodie (the most successful Escort driver at club level during 1970), owned by Richard Lloyd, the public relations consultant, and backed primarily by the Gold Seal Sports Car Centre, it has won six club races for modified sports cars and holds the Brands Hatch Club circuit lap record. The writer was able to try the Gold Seal Elan recently and its track manners were so astonishingly refined that it seemed a good idea to explore, in print, the ways in which some of the lessons from this racing car can be applied to Lotus Elans acquired by our readers.

The current Elan Sprint has the latest Tony Rudd development of the 82.6-mm. by 72.8-mm. (1,558-c.c.) twin-cam engine and is no mean performer in standard form. The press road-test car we enjoyed did employ an r.p.m.-limiter, unlike some earlier Lotus demonstrators, but its 126 b.h.p. (nett) at 6,500 r.p.m. was enough to pull just under 141 cwt. of red and white Sprint from rest to 60 m.p.h. in little over seven seconds: a time that even the V12 E-type has to breathe hard to beat. The Big-Valve Lotus engine has a torque curve which peaks at 5,500 r.p.m. and 113 lb. ft. of torque. It incorporates some of the ingredients that the specialist engine builders have used in the past to extract more power from the twin-cam unit.

One man who has been involved with the Elan since its introduction, both for road and track use, is Ian Walker. He now runs Ian Walker Racing at 236, Woodhouse Road, London, N12, a company concentrating on road and competition preparation of twin cam and Ford power units in general. We asked him for a general outline of his recommendations for the Elan. Walker commenced by pointing out that his company do six stages of engine tune for the car at prices ranging from £40 to over £400, whilst braking, handling and transmission changes can be ignored, at least until the fourth stage of tune is applied. He doesn't like to release power output figures for his engines because the factory have recently stopped quoting gross figures in favour of the more realistic nett results. Instead Walker told us that the customer can expect anything from a 20 to 50% increase in brake horse-power. Usually IWR tackle the job of changing camshafts and substituting new carburetter jets before moving on to the cylinder head, which is carefully refined around the inlet and exhaust porting, machined on the face to increase compression, and fitted with bigger valves. At Stage 4 level, approximately 150 b.h.p., Walker recommends changing the front shock-absorbers for the adjustable type. Otherwise he reckons that the Elan is an ideal base to cope with extra power, though the axle ratio can be changed with advantage to suit a particular purpose. For example, 5 1/2 years ago IWR put a numerically higher differential into the rear of one of their Elan SE coupé, to find that the little car was accelerating to 100 m.p.h. in well under 20 sec. (nowadays the standard Sprint takes 21 sec. to repeat that exercise), which would probably suit the dedicated traffic-light fiend down to the tarmac.

So for practical road use one can concentrate mainly on modifying the power unit to give the kind of performance that you wish to have, but what happens when you want to race the car? It seems that there are two answers. Either shop around for a well-used ex-factory competition (and lightweight) Elan and rebuild it completely to incorporate suitable suspension for today's low-profile tyres, or build up a completely new car using a production backbone and glass-fibre body.

The latter method was used by the builder of the Gold Seal car in 1969. The gentleman who did the original work was Jeff Goodliffe, a director of British Vita Racing Team in Littleborough, Lancs. Just how successful he was can be seen from the fact that he won the 1970 Castrol-BARC Hill-climb Championship in the car. Goodliffe used a smaller capacity twin-cam engine than the present unit, which he planned to supercharge but never did, and also carried out the redesign of the front end to carry the wide-based wishbones of the Chevron formula car. That operation involved the manufacture of a small space frame "cradle" attached to the front of the standard backbone and enabled him to fit the uprights and disc brakes of the Chevron.

At the rear the suspension was based on Elan components, as were the brakes, the entire stopping system utilising aluminium Girling calipers. Koni shock-absorbers were fitted at the front and Armstrong adjustables at the rear, using suitably higher poundage racing coil springs. Under the present regulations the car has to use wheels no wider than 8 1/2 in. across the rim, and this ruling is complied with by fitting Minilites on all four corners. Dunlop 350 (Intermediate) compound tyres were hiding under those pronounced wheel arches for our test, though their 200/550 by 13 in. dimensions were said to be a little undersized by the regular driver. Brodie also said that the Elan would benefit from a rear anti-roll or sway bar to cut down body lean on fast circuits. Unfortunately most club drivers rarely see which way Silverstone or Brands GP circuits go, much less sort their cars out for 110 m.p.h. plus cornering ability.

When the car passed into Lloyd's hands for Brodie to conduct, the handling was not suited toward racing demands, so Charles Beattie in Feltham, West London, worked on it to produce the instant response at circuit racing speeds. Luckily the car was built up to incorporate easily adjustable suspension, so camber, ride and wheel alignment (toe-in and out) can be altered without a major fuss.

The biggest change under Lloyd's ownership was to install one of the big-capacity twin cams like those used by Brodie in his Escort, though instead of the saloon's 2,150 c.c. the sports-car class limit imposed the need for less than 2-litres, in fact its capacity is 1,974 c.c. This meant that a bore and stroke of 90 mm. by 77.62 mm. was needed, achieved by use of a new cylinder block, pistons, long-throw Gordon Allen steel crankshaft, and BRM steel connecting rods. All the machining was completed by Hillthorne Engineering of Hanwell, also in west London, whilst the assembly work was managed by Racing Services of Twickenham. Incidentally, the pistons are forged from blanks provided by Brodie to run in the linered bores. The credit for the big twin-cam concept (i.e., of nearly 2-litres) goes to Norman Abbot, who runs a specialist engineering business in Ilford, and has constructed some very clever and properly finished racing cars in his time, including a dainty Formula Three and an Escort with spaceframe independent rear suspension, hauled along by a Cosworth FVA engine!

When Racing Services had completed the Gold Seal Elan unit it was found to boast 178 b.h.p. at 6,800 r.p.m. and a very flat torque curve, culminating in 165 lb. ft. at 5,800 r p.m. One of the few original BVRT engine parts was the 12.5 c.r. cylinder head with all the right cams and valves already installed and ready to go.

The transmission of this torquey output was entrusted to the Ford-developed Bullet gearbox (based on the Cortina GT unit a long time ago) with close ratios, giving of their best when mated to a Borg and Beck clutch and 3.9:1 rear axle, which incorporates a Salisbury limited slip differential. The unlikely combination of Brabham and Zodiac driveshaft couplings relay the power via Brabham F2 shafts outboard of the differential.

The interior was left magnificently standard, even down to the electric windows, wooden dash and operable ventilation fan, but the exterior was distinguished by the paintwork you see on these pages, a copy of which is now featured on the Lotus John Player Specials. In fact, the original "pinstripe" paint effect came to Britain from the United States and it would not be surprising if we did not start to see a lot more sporting cars finished in this style.

Secured at all four points by safety harness, the writer hardly felt as if he was in a racing car when he looked around the interior. One could amuse oneself by flicking the electric window idly up and down whilst the owners were trying to relay important instructions, or popping the headlamps up and down and observing that it was a shame the radio had to go in favour of a proper chronometric rev-counter, even though all the standard instruments were connected up as well. Below the dashboard a combined oil and water temperature gauge was suspended, its function being to indicate 60 lb. of oil pressure from the dry sump system, and preferably less than 90° Centigrade on the section covering H2O otherwise there would be trouble brewing.

The car had already been fully warmed up by Brodie, so it was no trouble to start the engine and move quite smoothly away on to the club track at Silverstone. No more than three or four laps were needed to find that the car was exceptionally easy to handle, whilst circulating in roughly the same times as we had managed after considerably more exertion in the Blydenstein Viva, track tested earlier this year. The brakes seemed to lack feel, but a second session with the Elan toward the cooler evening revealed that, though they could be improved for a proper racing driver, they were quite adequate for this tester. Our fastest lap occupied 1 min. 6.4 sec. (87.18 m.p.h. average), compared to the class record of 1 min. 4.6 sec. (89.61 m.p.h.) set up by Norman Cuthbert in a lightweight Elan with a smaller twin-cam engine. The best lap came up after 15 laps or so, which serves better than any long-winded account to prove how easy it was to drive. Only snag that I know of is that the asking price would be £2,000 plus.—J. W.