Lancia Delta S4 group B (1985)

Engine
Group/Class	B/12	Homologation number: B276
Years active	1985 - 1986	Homologation start: 1/11/1985 Homologation end: 11/12/1991
Type	Abarth 233 ATR 18S, straight 4 cyl (see picture), 4 stroke, petrol engine	located centrally in front of rear axle longitudinally with 20^o 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. 51.16^o 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

Season

Entry		Rally event
Driver Codriver	Team	MC	SVE Entry list	POR	KEN	TdC	GRE	NZ	ARG	FIN	(CdI)	SR	RAC	(Oly)

Henri Toivonen Sergio Cresto SE038-215	works	1st
Henri Toivonen Sergio Cresto SE038-204	works		eng ine	with drawn
Henri Toivonen Sergio Cresto SE038-211	works					acci dent*
Markku Alén Ilkka Kivimäki	works	cam shaft
Markku Alén Ilkka Kivimäki SE038-220	works		2nd	with drawn
Markku Alén Ilkka Kivimäki SE038-222	works							2nd
Markku Alén Ilkka Kivimäki SE038-223	works								2nd
Markku Alén Ilkka Kivimäki SE038-224	works									3rd
Markku Alén Ilkka Kivimäki SE038-225	works											1st		1st
Markku Alén Ilkka Kivimäki SE038-226	works												2nd
Markku Alén Ilkka Kivimäki SE038-206	works					with drawn	eng ine
Mikael Ericsson Claes Billstam SE038-206	works							4th		5th
Mikael Ericsson Claes Billstam SE038-204	works						susp ens ion
Mikael Ericsson Claes Billstam SE038-214	works												eng ine
Miki Biasion Tiziano Siviero SE038-214	works			with drawn		with drawn	2nd
Miki Biasion Tiziano Siviero SE038-209	works								1st
Miki Biasion Tiziano Siviero SE038-219	works	68th
Miki Biasion Tiziano Siviero SE038-224	works							3rd
Miki Biasion Tiziano Siviero SE038-226	works											3rd
Jorge Recalde Jorge del Buono SE038-204	works								4th
Kalle Grundel Benny Melander SE038-223	works									6th
Paolo Alessandrini Alessandro Alessandrini SE038-223	Roncaglia OPR													6th
Dario Cerrato Giuseppe Cerri SE038-222	Joly Club/Totip											2nd
Ignacio Sunsundegui (Stradale) Isaez de Buruaga		70th
Fabrizio Tabaton Luciano Tedeschini SE038-203	Grifone / Esso											with drawn

Total points ()	148	10	9				9	24	26	19		27	9	15
Statistics
Works starts/finishes	28/17	3/2	2/1	3/0		3/0	3/1	3/3	3/3	3/3		2/2	2/1	1/1
Others starts/finishes	4/3	1/1										2/1		1/1