LOTUS SEVEN REGISTER
the web site for the
Seven made by Lotus between 1957 and 1973
June 1960 to August 1968.
CHASSIS NUMBER SEQUENCE:
SB1000 to SB2310 which include the export "America" model. Early left hand drive cars had the usual 'SB' prefix; later left hand drive cars had either 'SBL' or 'LSB' prefixes.
Approximately 1310. Mostly at Delamare Road, Cheshunt, Hertfordshire than latterly at Hethel, Norwich, Norfolk.
Multi tubular space frame chassis, firstly by Progress Chassis Company(?), then at Universal Radiator Company and latterly by Arch Motors(?) with aluiminium transmission tunnel and floor acting as stressed members. Engine and gearbox rubber mounted. Transmission tunnel supports gearbox mounting. Front licence plate support bracket on some cars (Mostly USA spec, cars but UK cars also.)
Aluminium clad body with g.r.p. nose and wings in red, green and yellow by various contractors. Other colours also available at various times (at extra cost?). Front wings were either static cycle type or clamshell type on "America", "Super" and "1500" models or as an extra. Rear wings were 7 1/2" wide as standard but to accommodate wider wheels and tyres 9 1/2" were supplied as an optional extra later in production. Weather equipment in "Double Wigan" material.
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 upto late 1962(?) - 1172cc. FORD 100E side-valve engine developing variously between 28bhp and 36bhp at 4,500rpm with either Solex down-draught or twin side-draught SU H2 carburettors on Lotus manifold. Compression 7.1:1. Matching 3-speed gearbox and 100E gearknob. Standard ratios 3.894:1, 2.007:1, 1:1. Reverse 4.79:1. Close ratios ('C' type Buckler gears.) 2.294:1, 1.255:1, 1:1. Reverse 3.42:1.
Available upto late 1963(?) - 948cc. (a few 1098cc.) BMC "A" SERIES overhead valve engine in two forms - For the home market, Austin A35 with one side-draught H2 SU carburettor developing 37bhp at 5,000rpm. Compression ratio 8.9:1 and for the U.S. market ("America" model), Austin Healey Sprite (Mk. 1 'frog-eye') engine with twin side-draught H1 SU carburettors on Lotus or standard Sprite manifold (From 1961 HS2 1 1/4" SU carburettors on standard Sprite manifold) developing 43bhp at 5,200rpm. Compression ratio 8.3:1. Matching 4-speed gearbox and gearknob. Standard ratios 3.64:1, 2.38:1, 1.41:1, 1:1. Reverse 4.67:1. Close ratios 2.57:1, 1.68:1, 1.232:1, 1:1. Reverse 3.31:1.
Available between January 1961 and early 1968 - 997cc. FORD 105E overhead valve engine with twin side-draughtH2 SU carburettors on Lotus manifold developing 39bhp at 5,000rpm. Compression ratio 8.9:1. Matching 4-speed gearbox using Triumph Herald remote and gearknob with special adaptor plate on most cars but a few 116E gearboxes with Ford GT remote and gearknob at the end of production. Standard ratios 4.118:1, 2.396:1, 1.412:1, 1:1. Reverse 5.404:1. Close ratios (Hobbs?) 2.917:1, 1.696:1, 1.280:1, 1:1. Reverse 3.83:1.
Available between mid 1961 and September 1962 - "Super Seven" - 1340cc. FORD 109E COSWORTH Mk. V overhead valve engine with paired Weber 40DCOE2 twin-choke, side-draught carburettors on special manifold in two forms - For the home market developing 85bhp at 6,000rpm with a compression ratio of 9.5:1 and for the U.S. market with more torque for S.C.C.A. competition work developing 85bhp at 6,000rpm with a compression ratio of 10.5:1. The S.C.C.A. version was still available in 1964. Matching 4-speed gearboxes using Triumph Herald remote and gearknob with special adaptor plate; ratios as for Ford 105E above. Close ratios standard with S.C.C.A. specification.
Available between September 1962 and early 1968 - "Super Seven" - 1498cc. FORD 116E overhead valve engine with 5-bearing crankshaft in various states of tune. "1500 Standard with single Weber 40DCOE2 twin-choke, side-draught carburettor on special manifold developing 66bhp at 4,600rpm with compression of 8.3:1. "1500 Cosworth" (Mk. VIII) with paired Weber 40DCOE2 twin-choke, side-draught carburettors on special manifold developing 95bhp at 6,000rpm with a compression ratio of 9.5:1.. "1500 Cosworth" (Mk. IX - for racing) as above but developing 125bhp. "1500 Cosworth" (Mk. XIV - for fast road) as above but developing 100bhp. Matching 4-speed gearboxes with Triumph Herald remote and gearknob and special adaptor plate pre 1964 and Ford remote and gearknob later. Standard ratios 3.54:1, 2.397:1, 1.412:1, 1:1. Close ratios (Hobbs?) 2.51:1, 1.636:1, 1.23:1, 1:1.
Available from early 1968 - Known as the Series 2 1/2 - 1600cc. FORD 2255E overhead valve engine with crossflow head and Weber 32DFM twin-choke progressive down-draught carburettor in standard tune developing 84bhp at 5,500rpm. Compression ratio 9.0:1. 116E gearbox and GT remote and gearknob.
'Live' rear axle from Standard 10. 4.5:1 final drive to most early cars. 4.11:1 later.
Front are Girling hydraulically operated two leading shoes cast-iron drum type of 8" x 1 1/4". 9" disc types to all 1500cc. models. Rear are Girling hydraulically operated leading and trailing shoe cast-iron drum type of 7" x 1 1/4". Mechanical handbrake via horizontal lever.
Triumph Herald lightweight rack and pinion steering gear, universal jointed column and 16" diameter two-spoke steering wheel (grey plastic by Wilmot Breedon). Springhall 14" diameter woodrim to 'Super' models and later cars.
WHEELS & TYRES:
3 1/2" x 13" diameter well-based bolt-on rims by Dunlop. 4 1/2" x 13" Lotus Elan type bolt-on rims by Rubery Owen supplied later at extra cost.. All with chromium plated hubcaps. 520 x 13 (crossply) tyres as standard, radial and Dunlop R5 racing tyres at extra cost.
Heavy duty 12 volt 31 amp/hr battery weighing 24lbs. and from March 1964 12 volt 57 amp/hr weighing 29lbs. located on left hand side of bulkhead. Coil and distributor, centrifugal advance and retard, belt driven dynamo, automatic voltage control. Fuse box mounted behind the dash panel. Either Lucas L516 side lamps and seperate front indicators or Lucas L1130 side/flasher lamps. Either Lucas driving lamp SLR 576 and fog lamp SFT 576 or Lucas S700 7" double dipping headlamps with Lucas 7002 or GEC 6012 sealed beam units. Wingard 1055 combined rear and stop lights pre August 1965 and Thorpe PT 675 later. Lucas L539 flasher lamps to later models, Lucas HF1849 high frequency horn. Instrument lighting. [Extract from a Lucas Catalogue]
2" AC Ammeter, 2" AC Oil Pressure Guage (mechanical type), 2" AC Water Temperature Guage (capillery type), 3" AC 100mph Speedometer (Ford 100E, 105E and BMC "A" Series engines) or 3" Smiths 120mph Speedometer (Ford 109E, 116E engines) and 3" Smiths Chronometric 8,000rpm Tachometer ("America" models) or 3" HEL (Alexander) 8,000rpm Tachometer early Super Seven models or 3" Smiths [RVI 1400/00] 8,000rpm Tachometer circa 1962 on. (Note: no fuel guage.).
All but maybe the last few Series Two cars had bright red plastic covered steel cockpit side panels and dashboard and matching PVC fabric to seat squabs and backrest. After 1964/5 the rear part of the transmission tunnel was covered in matching red carpet. The last Series Two cars may have had black trim as the Series Three.
5 1/2 gallon rear sited fuel tank (8 gallon from April 1962). Cockpit heater on later cars.
EX-WORKS PRICES (from factory ephemera)
September 1961 - Seven (Ford 105E powered) - £499.00
September 1961 - Seven 'A' (BMC "A" Series powered) - £511.00
September 1961 - Super Seven (Ford 109E Cosworth powered) - £599.00
Circa 1962/3 - Seven (Ford 105E powered) - £499.00
Circa 1962/3 - Super Seven 1500 (Ford 116E powered) - £585.00
Circa 1962/3 - Super Seven 1500 Cosworth (Ford 116E Cosworth powered) - £645.00
Circa 1965/6 - Super Seven (Ford 105E powered) - £585.00
Circa 1965/6 - Super Seven 1500 (Ford 116E powered) - £645.00
Circa 1965/6 - Super Seven 1500 Cosworth (Ford 116E Cosworth powered) - £695.00
Circa 1965/6 - Super Seven (less engine & gearbox) - £485-00
(Offered October 1961): On All Models: Close Ratio Gears (fitted & unfitted); Cockpit Tonneau Cover; Sidescreens; Flared Wings (standard on Super Seven); 13" diameter Steering Wheel (standard on Super Seven).
(Offered September 1962): On All Models: Tonneau Cover; Heater. On Non-1500cc. Models: Sidescreens; Flared Wings; Woodrimmed Steering Wheel & Badge; Electric Tachometer; Sealed Beam Headlamps; Electric Radiator Cooling Fan.
(Offered circa 1966): On 1500cc. Models only (Were all 1500cc. then?): Tonneau Cover; Heater; Exhaust Extension; Workshop Manual; Oil Cooler Kit; Close Ratio Gears; Radial Ply SP41 Tyres.
Wheelbase 7' - 4", Front Track 3' - 11 1/2", Rear Track 4' - 0 1/2", Overall Length 10' - 11 1/2", Overall Width 4' - 7", Height to top of screen 3' - 3 1/2", Ground Clearance 6".
Weight given in Owner's Manual 924lbs. However road test reports give: "A" Series car 960lbs. - 105E car 957lbs. - 109E car from 952/1015lbs. - 116E car from 1008/1064lbs.