Lancia Delta S4 group B (1985)
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Home » Rally Cars » Lancia Delta S4
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1984: Lancia Delta S4
1987: Lancia ECV
1988: Lancia ECV2
Development level
Group B
Group A
Group N
Production

On board: see video

Specifications

200 units built
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Group/Class B/12 Homologation number: B276
Years active 1985 - 1986 Homologation start: 1/11/1985
Homologation end: 11/12/1991
Engine
Type Abarth 233 ATR 18S, straight 4 cyl (see picture), 4 stroke, petrol engine located centrally in front of rear axle longitudinally with 20o inclination to the drivers side (LHD)
Capacity 1759.3 cc WRC: x 1.4 = 2463 cc
1988: x 1.7 = 2991 cc
Bore x Stroke (mm) 88.5 x 71.5
Compression ratio 7.1:1
Output power - torgue 410 - 450 HP / 8000 rpm
(480-550 HP / 8400 rpm)
46.0 kgm (451 Nm) / 5000 rpm
Main bearings forged steel crankshaft with 5 main bearings 52.9mm diameter connecting rod length between centers 140mm, big end bearing tunnel diameter 51.35mm
Materials block: aluminium alloy cylinderhead: cross flow aluminium alloy with hemispherical combustion chambers
Cams/valves 2 overhead camshafts (DOHC), belt driven 4 valves/cyl. - 16 valves total. 35.6mm inlet valve diameter, 30.6mm exhaust valve diameter. 51.16o angle between inlet valves axis and exhaust valves axis
Aspiration KKK K26 53269707040 (12 blades steel turbine 54.5/64.4mm in/out diameter, 12 blades aluminium compressor 46.2/66mm diameter) turbocharger, EVO: KKK K27 (12 blades steel turbine 64/76.2mm in/out diameter, 12 blades aluminium compressor 57.4/82mm diameter) turbocharger combined with Abarth Roots Supercharger with 2 intercoolers (see picture), IAW Weber-Magneti Marelli multipoint electronic fuel injection pressure: 2.2 bar (560 HP)
Ignition Weber-Magneti Marelli electronic
Cooling system jacketed watercooled with pump, front and rear radiators, fan and thermostat
Lubrication system dry sump with 3 stage pump
Transmission
Type four wheel drive Hewland, 5 speed manual gearbox
Gearbox ratios 1st: 2.50/1 (35/14)
2nd: 1.579/1 (30/19)
3rd: 1.115/1 (29/26)
4th: 0.862/1 (25/29)
5th: 0.709/1 (22/31)
R: 2.461/1 (32/15 x 15/13)
1st: 2.385/1 (31/13)
2nd: 1.706/1 (29/17)
3rd: 1.350/1 (27/20)
4th: 1.136/1 (25/22)
5th: 1.000/1 (26/26)
R: 2.500/1 (35/16 x 16/14)
1986:
1st: 2.538/1 (33/13)
2nd: 1.706/1 (29/17)
3rd: 1.250/1 (25/20)
4th: 1.000/1 (23/23)
5th: 0.840/1 (21/25)
R: 2.500/1 (35/16 x 16/14)
Diffrential ratio Front/rear 2.643/1 (37/14),
Center differential 2.000/1 (42/21), 1.773/1 (39/22), 1.905/1 (40/21), 2.000/1 (40/20), 2.263/1 (43/19), 2.278/1 (41/18).
1986: center differential 2.100/1 (42/20), 2.150/1 (43/20)
helical gears ferguson viscous coupling epicyclic center differential with adjustable distribution 25%-75% to 40%-60% front to rear and 2 outputs, 1st to ZF spiral bevel gear limited slip front differential and 2nd to ZF spiral bevel gear limited slip rear differential
Clutch dry, double disk
Chassis-body
Type chrome-molybdenium tubular space frame with carbon fiber reinforcements chassis, front and rear tubular suspension subframes. 2 door hatchback/coupe carbon fiber composite bodyshell. Bonnet opening behind the front-mounted water radiator with Gurney flap, front splitter and winglets moulded into the front bumper panel, flexible front skirt, and rear deck lid wing that featured both a full aerofoil wind section twinned with a deflection spoiler. The door construction style was brought from the 037 with a hollow shell all-Kevlar construction that had no inner door skin, no door handle or window winder. The door was opened with a small loop and the windows were fixed perspex with small sliding panels to allow ventilation
Front suspension double unequal wishbones, coil spring, telescopic hydraulic shock absorbers, anti-roll bar
Rear suspension double unequal wishbones, separate spring, twin telescopic hydraulic shock absorbers, anti-roll bar
Steering system rack and pinion with or without pneumatic power assisted 2.5 turns lock to lock, 14.4/1 ratio
Brakes front and rear ventilated disks 300mm diameter, front 2 aluminium piston calipers 48mm diameter or 4 aluminium piston calipers 42+40mm diameter (1 pair of pistons is 42mm diameter, and the other is 40mm diameter), rear 2 aluminium piston calipers 32/42/48mm diameter.
1986: front and rear 4 aluminium piston calipers 44+36mm diameter (1 pair of pistons is 44mm diameter, and the other is 36mm diameter)
dual circuit with servo, adjustable ratio split front to rear
Dimensions
length: 3.990 m (157.1")
EVO: 4.092 m (161.1")
width: 1.785 m (70.3")
EVO: 1.860 m (73.2")
height: 1.360 m (53.5")
wheelbase: 2.440 m (96.1") front track: 1.510 m (59.4") rear track: 1.535 m (60.4")
Rims - tires 8" - 10" x 16" Pirelli 205/55 VR 16, front 235/660 - 16, rear 290/660 - 16
Weight 900-1000 kg front/rear distribution 45% - 55%
Fuel tank 80, 70 - 110 lt

Results in WRC

Statistics

1985 1986 Total
Works
Races/wins 1/1 11/4 12/5
Entries/finishes 2/2 28/17 30/19 (63.3%)
Others
Races 0
Entries/finishes 4/3 4/3 (75.0%)
Total WRC results
Races/wins 1/1 8 12/5
Entries/finishes 2/2 32/20 34/22 (64.7%)
Total points 19 148 167
(13.917 per race)
(4.911 per entry)

Races

Works team: Martini Lancia

Season
Entry Rally event
Driver
Codriver
Team M.C SVE
Entry list
POR KEN TdC GRE N.Z ARG FIN S.R (CdI) RAC
Henri Toivonen
Neil Wilson
SE038-202
works 1st
Markku Alén
Ilkka Kivimäki
SE038-207
works 2nd
Total points
()
19 19
Statistics
Works starts/finishes 2/2 2/2

Information and articles

Article from 4T 182, 11/1985

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Wikipedia

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Street version

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62667fa4e1a6c39617f7f54ece373edd.jpg Source
Henri Toivonen in Monte Carlo '86 (snow)
tour-de-corse-1986-lancia-delta-s4-toivonen.png Source
Henri Toivonen in Tour de Corse '86 (άσφαλτος)
Lancia_Delta_S4_006.JPG Source
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Drawings

1024_s4_cutaway.jpg Source
lancia-delta-s4.gif Source
Lancia_Delta_S4_by_kaka_22.jpg Source
lancia-delta-s4.jpg Source

Engine

lanciadeltas41986227bhp.jpg Source

Rear suspension

lanciadeltas4rearsuspen.jpg Source

CAD

lanciaS4_02.jpg Source
lanciaS4_03.jpg Source
s4-cad.png Source
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