1969 Lotus Elan S4 SE Coupe
Ron Hickman designed the Elan around a pressed-steel backbone chassis (a direct response to the rigidity problems of the Elite’s fiberglass monocoque), and the configuration proved so effective that Lotus carried it forward for decades.
The fiberglass Drophead Coupé body sat over this frame at a total weight of around 1,499 lbs (680 kg), giving the 1,558cc twin-cam engine considerably more to work with than its displacement suggested.
The Series 4, introduced in March 1968, brought flared wheelarches for wider tires, a slightly thinner and lighter body, larger Plus 2-style taillights, and side repeater indicators. Fresh-air dashboard vents and improved interior trim made the S4 the most comfortable of the Elan variants.
Suspension was fully independent at both ends: unequal-length wishbones up front and a wide-based lower wishbone with a Chapman strut at the rear. Girling disc brakes were fitted all around.
The twin-cam was built on a Ford Cortina block with a Lotus-designed cylinder head (the work of Harry Mundy), and in SE specification ran twin Weber carburetors for a modest power increase to around 115 hp.
Total Elan production across all variants reached just under 9,000 cars before the line closed in 1973.
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