Porsche 550 Prototype Spyder Specifications
In late 1953, Porsche showcased a more definitive version of the 550 with a quad-cam engine and simple roadster body. Designed for a range of races from short course and hill climbs through to long distance endurance races, the engine and longer trailing arm suspension set up was different on the purpose built frame also made by Weinsberg.
Engine
- Type 547: Four cylinder 4 cycle, box motor, air cooler, horizontal opposed, 4 overhead camshafts
- Power: Approx 110 HP @ 6200 RPM
- Bore: 3.35 in (85 mm)
- Stroke: 2.59 in (66 mm)
- Piston Displacement: 1498 cm actual, from formula cubic 1487 cm
- Compression ratio: 9.5:1
- Crankcase: Aluminium
- Cylinders: Aluminium hard chromed walls
- Cylinder head: Aluminium
- Valves per cylinder: 1 intake, 1 exhaust
- Valve operation: 4 camshafts driven by 2 vertical shafts
- Crankshaft: Full roller bearing, built up
- Pistons: Aluminium
- Air blower drive: V-belt, crankshaft to generator shaft
- Crankshaft-blower ratio: 1:1
- Air volume: 1100 ltr/sec at 6200 RPM
- Engine lubrication: Dry sump, with oil cooler and oil filter in main current
- Firing order: 1-4-3-2
- Distributor drive: Camshaft
- Spark plugs: Temperature valve 260 – 280 C
- Carburetors: Solex 40 PJJ or Weber 40 DCM
- Muffler: 2 mufflers leading into 1 exhaust pipe
- Clutch: Fichtel & Sachs, K 12 Porsche Special
- Transmission: 4 forward speeds, helical gears, synchronized, 1 reverse
Gear ratio
- 1st gear: 11:35
- 2nd gear: 17:30 – 16:31 – 18:29
- 3rd gear: 23:26 – 22:27 – 24:25
- 4th gear: 27:22 – 25:24 – 26:23
- Reverse gear: 1:3.56
- Shifting: Ball and socket and push rods
- Rear axle: Spiral bevel pinion, ZF lock type differential
- Gear ratio: 8:35 – 7:31 – 7:34
- Top speed: 124 mph
Chassis
- Frame: Tubular, seamless steel tubing
- Front springing: 2 transverse, 4-leaf adjustable torsion bars
- Rear springing: 1 round torsion bar on each side
- Shock absorbers: Fichtel & Sachs, telescopic hydraulic
- Front: 26 x 90
- Rear: 36 x 140 HA
- Front wheel suspension: Longitudinal suspension arms, outside needle bearings
- Rear wheel suspension: On oscillating half axles
- Steering: Special worm gear with divided tie rods
- Steering ratio: 1:14.15
- Operating brakes: Oil hydraulic foot brakes to all four wheels
- Parking brake: Hand lever operating cable to rear wheels
- Brake drums: 11.0236 in (280 mm)
- Brake lining width: 1.5748 in (40 mm)
- Total effective surface: 115 sq in (744 sq cm)
- Wheels: Disc
- Rims: Aluminum
- Tyres front: 5.00 – 16 in
- Tyres rear: 5.25 – 16 in
Dimensions & Weight
- Wheel base: 2101 mm / 82.7 in
- Front tread: 1290 mm / 50.8 in
- Rear tread: 1250 mm / 49.2 in
- Dry weight: 550 kg / 1213 lbs
Electrical Accessories (6 volt)
- Battery: Varta Special 6 V/70 amp
- Starter: Bosch EED 0.4/6 L 18 / Bosch LI/GE 160/2 2500 L 10
- Generator: (LI 20/1 P 45)
- Voltage regulator: Bosch RS/UA 160/6/15
- Distributor: Bosch 2 V 2/6 K 10
- Coil: Bosch TK 6 A/5
- Spark plugs: Bosch W 260 T 2 – W 270 T 17 or equivalent type
- Ignition switch: Bosch SH/ZS 1/1
- Starter switch: Kirsten 5232
- Light switch: Kostal 7473/3 with voltage regulator
- Beam deflector switch: Bosch SHNF 2/1
- Blinker unit: SWF 2 x 20 watt, Type BGA
- Blinker switch: Bosch SH 12/27 HI (2 circuit) without bulb
- Brake light switch: Teves (On master brake cylinder)
- Head lights: Bosch LE/YE 180/X 2/7
- Blinker and park light: Bosch LE 14/16 N 2
- Tail, brake, blinker & back up lights: Bosch LE 14/16 N 1
- License plate lights: SWF EL 153-1
- Horn: Bosch HO/EZ 32/32 D 1 or D 2
Price
- List price (1955): US$6,800.00
