Lotus Elan 1600 (Car and Driver 2/64)
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Magazine Title: | Car and Driver |
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Published: | February 1964 |
One of the daily office bull sessions, a few months ago, got off on the nature of enthusiasm and other similarly esoteric subjects, and we were wondering what the 1963 enthusiast drives. Fifteen years ago, he was in an MG-TC with no windscreen, or some kind of bellowing Allard. Nowadays, we decided, a true enthusiast, a real purist, ought to have a Lotus 23 to drive on the streets, since that fantastic car is about as extreme-and pure-an example of sporting automobile as there is around.
That was before we'd driven the Elan. Now, blanching at the prospect of trying to protect a 23 in modern traffic on one hand, and having sampled the joys of the Elan on the other, we'd like to make a substitution. The Elan very simply represents the sports car developed in tune with the state of the art. It comes closer than anything else on the market to providing a Formula car for ordinary street use. And it fits like a Sprite, goes like a Corvette, and handles like a Formula Junior.
Driving it is very simply another sort of automotive experience altogether. Most people tend to come back from their first ride a little bit glassy-eyed; the knowledgeable usually remark that the car reminds them of nothing so much as a Formula Junior. What you will get from a Lotus Elan that you aren't apt to be able to experience in a Junior, is the absolute joy of charging -under all sorts of conditions and in all kinds of circumstances. A combination of the very tiny exterior dimensions of the car, the great acceleration and stopping power, and the complete, reliable safety of it, makes hurrying into a pretty good sport in itself.
That safety aspect is perhaps the strongest impression the car makes. Underway, it seems less a car than a system, with its elements complementing each other well enough to pretty well wipe out previous notions of how a car should go. Safety comes in other forms than massive padding--a well-balanced, positive, and predictable chassis, as in this case, will do.
Almost everything about the Elan seems to represent a complete reversal of Colin Chapman's design philosophy, as exemplified by the unit-construction fiberglass bodied Elite and the monocoque Lotus 25 Grand Prix car. The Elan is built up on a deep box-section steel backbone frame with something like six times greater torsional stiffness than the structure of the Formula One vehicle. Chapman also breaks with past Lotus practice in the Elan suspension, and relies on Ford for the complete engine and drive train.
Backbone frames have almost disappeared since unit construction came into vogue, but they were quite popular in pre-war days. The original backbone frame was designed by Edmund W. Lewis and used on the 1904 Rover, but the design which the Elan chassis brings to mind is the R-Type MG of 1935, designed by H.N. Charles. The similarity of concept and execution between these two cars is so striking that one is tempted to conclude that Chapman took his inspiration for the Elan from the single-seater MG. The R-Type had a backbone steel frame of immense structural strength, and wishbone-type independent suspension front and rear, but used torsion bars rather than coil springs as on the Elan.
The Elan frame forks out at both ends to resemble a cruciform structure, with the front triangle providing room for the engine and gearbox and attachment points for the front suspension, while the rear triangle provides a base for the rear suspension and final drive. The frame is made of 18-gauge steel (0.048-in. thickness) with 16-gauge (0.064-in. thickness) reinforcements. The center section, which makes up the console between the two seats, has a width of six inches and a depth of 11 1/2 inches. The frame is drilled for lightness and weighs only 75 lbs.
The body is a fiberglass shell with metal reinforcements for the doors and windshield. It is itself a unit structure and does not rely on the backbone frame for stiffness. The same theory has been applied with steel bodywork on the Triumph Spitfire, which also has a very rigid frame. The Elan body rests on the frame midriff and has 14 additional mountings-10 on the lower edge of the frame and 4 on the suspension pillars. The fiberglass structure is manufactured by S. Bourne of Nottingham and shipped to Lotus at Cheshunt in Hertfordshire for assembly and finishing.
Front suspension on the Elan follows the main principles laid down in the Elite, with unequal-length wishbones and narrow-diameter coil spring-and-shock absorber struts. The normal setting for the front wheels of the Elan gives one degree of positive camber.
While the rear end of the Elite has a lower transverse link and uses the half-shafts as upper locating members, the Elan has lower wishbones only and positive top location via the Chapman suspension struts, relieving the half-shaft of all location duties. The shafts still have fixed length, but some flexibility is provided by the Metalastik universal joints. Like Lotus racing designs, spring rates on the Elan are as low as possible, keeping the wheels in constant contact with the road and giving a ride comfort far superior to any other sports cars-if not better than many luxury sedans!
As befits a Chapman design, the Elan's cornering power is simply phenomenal. It's a considerable improvement on the 1955 Lotus 11, which first established modern standards for high-speed small-displacement sports cars. Going through a corner progressively faster with the Elan, it first drifts, then slides and makes a low cat-like growl when the limit of propriety is approached. It then crouches and goes still faster. But there is never anything untoward or unexpected everything merely happens faster than with other cars because this one can be cornered faster.
The car has absolutely neutral handling characteristics, and wonderfully quick steering response with all the accuracy of a racing machine. And just like the old Lotus 11, the car won't do anything funny if the driver uses the brakes well into a corner-it will stay right on the intended line. Changes in throttle opening affect its course so slightly as to be of no moment.
Our test car was fitted with Goodyear Tubeless tires, a mistake that the importer was happy to acknowledge. Later cars will be fitted with a more suitable Dunlop tire, and the car will undoubtedly be more controllable in the wet and quieter during cornering on the dry.
For a large driver, the Lotus Elan borders on being too small. Pedal placement is as good as possible, but the narrow tunnel just doesn't give enough space for really good location. As a result, heeling-and-toeing is possible for the big-footed, but you ought to wear nice tight shoes to try it. The brake foot tends to catch a bit of the gas pedal when you don't want it to, and you have to slide your clutch foot under the clutch pedal to rest it-or to dim the lights. We found ourselves lifting only our toe to get off the accelerator pedal, and thinking the throttle was stuck; it was just that we were still holding the gas pedal down with the arch of our foot. Detail changes are planned.
The result of all this is that a larger driver will feel unnaturally clumsy in the tiny car, as a first impression. The evidence of a quick and vital kind of response is so apparent that he'll blame himself, feeling guilty for manhandling a thoroughbred. Then, as miles accumulate, things start falling into place, and the driving procedure becomes a kind of whirling tap dance, with only a touch needed here and there, a soft, light, effortless controllability. But it is truer of the Elan than of most cars that you need to put some time in before the car begins to work properly for you.
The seats of the Elan are less extreme in the angle of reclining than on any other Lotus, including the Elite. The backrests are not adjustable, but the fixed angle will suit most drivers who prefer a straight-arm position. Short drivers are aided in their efforts to see out by the fact that the seat moves upward as it is moved forward.
Attractive is unquestionably the wood for the interior, which is nice but not terribly practical. There's a shortage of stowage space almost as striking as in the XK-E and ridiculously small ashtrays built into the door panels. The instrument panel is spartan compared with such cars as the Sunbeam Alpine, but we must admit we found it adequate.
Weather protection is a chronic problem with all sports cars, and the Elan is no exception. There are water leaks by the door posts, and the windows juggle down from a closed position as the car progresses, creating drafts and leaks galore. But what the hell it's still better than many sports cars that we have come to accept as they are (and try to drive only on nice days). The floor of the Elan is as tight as a space suit, so the car can be driven through sizeable pools and puddles without fear of getting wet feet. The Elan's soft top fits nicely and does not flap in the wind, but does create some noise at speed. Removal of the top is no worse or no better than average for an open British two-seater. One man can complete the operation by himself, but if he's in a hurry, it's nice if he has help.
Of the controls in the Elan we have only one strong objection-the handbrake. It's of the umbrella-handle type and is concealed under the dash. We found we used it very little, while on such cars as the Spitfire, MG-B and Fiat 1500 we employed it very frequently. Handbrakes can be very useful, and the least we can ask is that they be conveniently arranged.
Vacuum-operated retractable headlights have the great advantage over the electrical ones that the delay is only about one second from the time the button is pulled until the headlights are in position. On the Elan the light switch is right next to the retractor button, easily within reach of the right hand.
Luggage? Well, better bring a trailer if you are taking a long trip, but there's enough space in the trunk of the Elan for what any sports car owner would need for a long week-end. There's also some space behind the seats which can be used for bags and brief-cases without inconvenience.
The ancestry of the twin-cam Lotus-Ford engine starts with the 997cc power plant of the new Anglia, the design of which began in 1954 and was introduced in 1958. This unit was known as the 105-E and was intended as the basis for a series of lightweight engines of various larger displacements. The first step was the 109-E which was used in the Ford Consul Classic. The enlargement from 997cc to 1340cc was made without any alteration in bore (80.96mm) but achieved entirely by giving the engine a new crankshaft with a longer throw, increasing the stroke from 48.41mm to 65.09mm. Both the 105-E and the 109-E had three-bearing cast crankshafts with hollow crank webs. A major redesign was put in hand for the 116-E; it was given a five bearing crankshaft (with solid webs) and a new cylinder block with the identical 80.96mm bore but enough extra height to allow a stroke increase to 72.75mm, giving a displacement of 1498cc. The weight increase was only 15%, for a 50% displacement increase over the original engine.
The 116-E became the basis for the Lotus twin-cam conversion. The block was bored out to 81.6mm while the stroke was kept at 72.75mm, giving a displacement of 1558cc. The light alloy twin overhead camshaft cylinder head was designed and developed by Lotus, not by Ford. The resultant engine was first used, in 1498cc form, in the Lotus 23 which made such a sensational debut at Nurburgring in 1962, and it became the power plant of the Lotus-Cortina that autumn.
Then Colin Chapman introduced the Elan, with the same engine but a different transmission from that used in the Cortina. The Elan transmission is a close ratio version of the gearbox used in the new Ford Consul Corsair.
The task of designing the dohc head was complicated by the necessity of retaining as many Ford parts as possible, in the interest of keeping production costs down. Ford uses weight-graded pistons, which would be suitable for a high-performance engine, and it was decided not to replace them just to obtain a higher compression ratio. But with flat-topped pistons in a highly oversquare engine it is difficult to obtain a sufficiently high compression ratio for power outputs of competitive level to be reached. The solution was to use a quite narrow valve angle (54 degrees included) and letting the combustion chamber overlap the cylinder bore by 0.34 inches. This gave the engine a compression ratio of 9.5 to one, without any restrictions on valve size, gas flow or turbulence. The engine is redlined at 6500 rpm but is willing to rev to well over 7000. Peak power is developed at 5500 and maximum torque at 4000, but what is most surprising in this high-speed unit is that brake mean effective pressure never falls below 134 psi between 2000 and 6000 rpm. It is a unique combination of racing car and tractor engine and remarkably silent at all speeds.
Apart from the closer ratios, the only difference between the standard Corsair transmission and the one used in the Elan is the Lotus shift linkage. It's an all synchromesh four-speed but the synchromesh is not particularly effective on rapid changes and can be beaten on all gears.
The final drive is taken straight from the Ford Consul Classic and mounted in a Lotus-designed aluminum housing. This unit was of course intended for transmitting much less torque than the Elan engine puts into it, and we can only speculate as to its life expectancy. The final drive also tends to be noisy on the overrun.
Clutch action is as sudden as in a competition car. It immediately takes a tenacious grip and the car is under way. It's possible to spin the rear wheels, first when moving off from standstill and again when shifting into second, but even in the absence of a limited slip differential there's no fishtailing. This type of clutch is great for lightning getaway at the traffic lights, and once one is used to its action, parking and maneuvering is no problem.
Aerodynamics of the Elan are very good, and we agree that the design is extremely clean and functional. Its directional stability is certainly far superior to the rest of its weight class, and the car is quite acceptable for turnpike driving. Instead of the usual wind blast from the big trucks, there's a gentle, controllable pressure which hardly calls for steering corrections.
In fact the sleek, small slipperiness of the car is its most endearing quality. The wonderfully soft ride combined with infinite controllability and tenacious road grip, the very low noise level linked somehow to so much solid power in a small displacement sports car, point up the very dual nature of the car. You used to have to put up with a lot to use a racing car on the street. Here's one that can be expected to acquit itself well in club events with little change. The importers emphasize the opposite, that the car should not be raced without extensive preparation. But no matter what was done to prepare the car, you would give away little or nothing in creature comforts and tractability. We look forward to the next opportunity to drive one with the same feeling that makes skiers look forward to winter and kids look forward to vacations.
Road Research Report: Lotus Elan | ||||
Importer: | Cox & Pulver, Inc. | |||
233 East 70th Street, New York 21, N.Y. | ||||
PRICES: | Basic price $4295.00 POE East Coast | |||
ENGINE: | ||||
Water-cooled four-in-line, cast-iron block, 5 main bearings. | ||||
Bore x stroke | 3.25 x 2.86 in, 82.55 x 72.75 mm | |||
Displacement | 95 cu in 1558 cc | |||
Compression ratio | 9.5 to one | |||
Carburetion | 2 Weber side-draft DCOE/2 | |||
Valve Gear | Twin chain-driven overhead camshafts | |||
Valve diameter | Intake 1.62 in, exhaust 1.46 in | |||
Valve timing | ||||
Intake opens | 22 BTC | |||
Intake closes | 62 ABC | |||
Exhaust opens | 62 BBC | |||
Exhaust closes | 22 ATC | |||
Valve lift | 0.35 in. | |||
Power (SAE) | 105 bhp @ 5500 rpm | |||
Torque | 108 lb-ft @ 4000 rpm | |||
Specific power output | 1.1 bhp per cu. In. 67.5 bhp per liter | |||
Usable range of engine speeds | 1500-7000 rpm | |||
Electrical system | 12-Volt, 57-amp-hr battery, 300 W generator | |||
Fuel recommended | Premium | |||
Mileage | 22-28 mpg | |||
Range on 12-gallon tank | 265-335 miles | |||
DRIVE TRAIN: | ||||
Clutch: | 8 1/2-inch single dry plate | |||
Transmission: | 4-speed all-synchro gearbox | |||
Gear | Ratio | Overall | mph/1000 rpm | Max mph |
Rev | 2.92 | 11.38 | -5.9 | -41 |
1st | 2.51 | 9.78 | 6.8 | 47.5 |
2nd | 1.7 | 6.63 | 10.2 | 71 |
3rd | 1.23 | 4.8 | 13.9 | 97 |
4th | 1 | 3.9 | 17.1 | 112 |
Final drive ratio | 3.9 to one | |||
CHASSIS: | ||||
Backbone steel frame and monocoque fiberglass body. | ||||
Wheelbase | 84 in. | |||
Track | 47 in. | |||
Length | 145 in. | |||
Width | 56 in. | |||
Height | 45 in. | |||
Ground clearance | 6.0 in. | |||
Dry weight | 1420 lbs | |||
Curb weight | 1486 lbs | |||
Test weight | 1715 lbs | |||
Weight distribution front/rear | 48/52 | |||
Pounds per bhp (test weight) | 16.5 | |||
Suspension: | ||||
F: | Ind., wishbones and coil springs, anti-roll bar. | |||
R: | Ind., lower wishbones and coil springs on Chapman struts. Brakes Girling 9 1/2-in discs front, 10-in discs rear, 358 sq in swept area | |||
Steering | Rack and pinion | |||
Turns lock to lock | 3 ?/? | |||
Turning circle | 30 ft. | |||
Tires | 5.20 x 13 | |||
Revs per mile | 896 | |||
MAINTENANCE: | ||||
Crankcase capacity | 3.75 quarts | |||
Oil change interval | 5000 miles | |||
Number of grease fittings | 3 | |||
ACCELERATION: | ||||
Zero to | Seconds | |||
30 mph | 3.2 | |||
40 mph | 3.3 | |||
50 mph | 5 | |||
60 mph | 7.1 | |||
70 mph | 9.8 | |||
80 mph | 12.9 | |||
90 mph | 17 | |||
100 mph | 22.1 | |||
Standing quarter-mile | 15.7 @ 87 mph |