LOTUS SEVEN REGISTER
the web site for the
Seven made by Lotus between 1957 and 1973
September 1968 to January 1970.
CHASSIS NUMBER SEQUENCE:
SB2311 to SB2649. The 13 Twin-Cam SS cars had the chassis number prefix 'SC'. Left hand drive cars had the prefix 'LSB'.
Approximately 340 at Hethel, Near Norwich, Norfolk.
Multi tubular space frame chassis by Universal Radiator Company and Arch Motors with aluminium transmission tunnel and floor acting as stressed members. Engine and gearbox rubber mounted. Transmission tunnel supports gearbox mounting.
Aluminium clad body with self-colour g.r.p. nose and wings in Red, Green and Yellow by various contractors. Other colours at extra cost. Front wings 'clamshell' type.
Independant by transverse wishbones incorporation anti-rollbar. Springing by combined coilspring damper units reacting through a single attachment point at each end. (Dampers by Armstrong.)
Proprietary 'live' rear axle located by a pair of trailing arms [upper] and a triangulated 'A' bracket with apex picking up beneath the axle casing [lower]. Springing by combined coilspring damper units. (Dampers by Armstrong.)
STANDARD ENGINES AND GEARBOXES:
Available to January 1970 - 1600cc. FORD 2255E CROSSFLOW overhead valve engine with Weber 32DFM twin choke progressive down-draught carburettor in standard Ford Motor Company tune developing 84bhp at 5,500rpm. Coopers air cleaner. Compression ratio 9.0:1. Gearbox, remote and gearknob as for 116E engine. Also available at the same time although very rare in a Seven - similar 1300cc. unit developing 72bhp at 5,500rpm.
Available from January 1969 - LOTUS HOLBAY CFR 1600 engine, a tuned version of the Ford 2255E (above) with twin Weber 40DCOE2 side-draught Webers developing 120bhp. Compression ratio not stated. Gearbox and remote as for 116E engine, gearknob Lotus 'ball' with black badge.
Available from October 1969 - 1558cc. LOTUS TWIN-CAM engine with twin 40DCOE Weber carburettors either in standard 'Special Equipment' tune (115bhp) or as the Lotus-Holbay version (125bhp). Gearbox as before but with uprated second gear.
'Live' rear axle from the Ford Escort Mexico with modified Lotus casing. Standard ratios 3.77:1 for 1600cc. engine and 4.12:1 for 1300cc. engine. Options 3.9:1 ratio and limited slip differential.
Front are Girling (Triumph Spitfire) hydraulically operated 9" disc type to all models. Rear are Girling hydraulically operated leading and trailing shoe cast-iron drum type of 7" dia. x 1 1/4". Mechanical handbrake by horizontal lever.
Triumph Herald lightweight rack and pinion steering gear, universal jointed column and 14" diameter black PVC covered 3-spoke aluminium steering wheel.
WHEELS & TYRES:
5 1/2" x 13" diameter well-based bolt on steel rims with chromium plated hub-caps. 13" light alloy bolt-on rims (Brand Lotus) at extra cost. All with radial ply tyres as standard.
ELECTRICS: (Now NEGATIVE EARTH system)
12 volt 39 amp/hr battery located on left hand side of bulkhead. Either Lucas L516 side lamps and seperate front indicators or Lucas L1130 side/flasher lamps, Lucas S700 7" double dipping headlamps with Lucas 7002 or GEC 6012 sealed beam units, Thorpe PT 675 combined rear and stop lights, Lucas L539 rear flashers. Lucas twin windscreen wipers. High frequency horn. Instrument lighting. [Extract from a Lucas Catalogue]
AC shrouded Ammeter and Fuel Guage and Smiths combined Oil Pressure and Water Temperature Guage, 120mph Speedometer and 8,000rpm Tachometer. Sometimes all instruments were Smiths.
Black pile carpets with matching weatherproof trim and black PVC ventilated seat squabs and back rest.
Heater. 8 gallon Fuel Tank with filler point in rear body panel.
EX-WORKS PRICES (from factory ephemera):
Circa 1968/9 - Seven (Ford 225E 1300cc & 1600cc powered) - £775.00
On All Models: Four Branch Exhaust Downpipe, Close Ratio Gearbox, Engine Tuning Equipment, Light Alloy Wheels (Dunlop?), Optional Paint Specification, Roll Over Bar, Seat Belts, Oil Cooler, Tonneau Cover, Heater, 3.9:1 Axle Ratio, Limited Slip Differential.
Wheelbase 7' - 5", Front Track 4' - 1", Rear Track 4' - 4", Overall Length 10' - 11 1/2", Overall Width 4' - 7", Height to top of screen 3' - 3 1/2", Ground Clearance 6".
None given in Owner's Manual. However road tests give the following:-
Autosport 1969 - Lotus Seven "S" - 1204lbs.
Autocar 29/1/70 - Lotus 7 Twin-Cam SS - 1254lbs.
Road & Track Oct 1970 - Lotus 7 Twin-Cam SS - 1210lbs,