Ford Model T — Detailed Engineering Specifications
From The Model “T” Chassis — Detailed Engineering Specifications, 1926–27, Archives Department, Ford Motor Company.
Engine — General
| Engine | Model T |
| Engine Type | “L” Head |
| Bore & Stroke | 3¾″ × 4″ |
| Number of Cylinders | 4 |
| Cylinders Cast | “En Bloc” |
| Piston Displacement | 176.7 cu. in. |
| Compression Ratio | 3.6 : 1 |
| N.A.C.C. or S.A.E. Rating | 22.5 |
| Maximum Brake Horsepower | 20 bhp |
| R.P.M. at Maximum H.P. | 1600 rpm |
| Engine Suspension | 3-point |
| Engine Firing Order | 1 — 2 — 4 — 3 |
| Cylinder Head Bolts, No. of | 15 |
Valves
| Material | Stem: cold rolled steel. Head: cast iron. |
| Valve Seat Angle | 45° |
| Valve Lift | .225″ |
Pistons
| Material | Grey iron casting |
| Weight (with pins & rings) | 2 lb 1 oz min., 2 lb 4 oz max. |
| Weight (piston only) | 1 lb 10 oz min., 1 lb 12 oz max. |
| Piston Rings, No. of | 3 |
Piston Rings
| Material | Cast iron |
| Kind of Ring | One-piece split ring, diagonal cut |
Wrist Pin
| Material | Machined seamless steel tubing |
| Diameter | .740″ to .741″ |
| Length | 3½″ |
Connecting Rods
| Material | Steel forging (I-beam section) |
| Length, centre of bearing to centre of clamp | 7″ |
Crankshaft
| Material | Drop forging, alloy steel, heat treated |
| Overall Length | 25 5/8″ |
| Total Weight | 14 lb 15 oz |
| Bearings, No. of | 3 |
| Crankshaft Gear | Steel teeth, 24 |
Crankshaft Bearings
| Diameter (Front / Centre / Rear) | 1.248″ / 1.248″ / 1.248″ |
| Length (Front / Centre / Rear) | 2″ / 2 11/16″ / 3½″ |
Camshaft
| Material | Steel forging, heat treated |
| Camshaft Speed | ½ engine speed |
| Camshaft Bearing Bushings | Cast iron |
| Camshaft Gear, Material | Malleable iron |
| Camshaft Gear, No. of Teeth | 48, noiseless spiral teeth |
Camshaft Bearings
| Diameter (Front / Centre / Rear) | .748″ / .748″ / .748″ |
| Length (Front / Centre / Rear) | 1.776″ / 2 1/16″ / 1¼″ |
Fly Wheel
| Location | Integral with magneto |
| Material | Cast iron |
| Number of Teeth | 120 |
| Ratio of Fly Wheel to Bendix Drive Gear | 12 : 1 |
Fuel System
| Carburetor Make | Ford — N.H. |
| Carburetor Size | 1″ |
| Tank Capacity — Square Tank | 9¾ gal. |
| Tank Capacity — Cowl Tank | 10 gal. |
| Tank Capacity — Oval Tank | 9½ gal. |
Cooling System (Thermo Syphon)
| Total Capacity | 25 pints (1 pint more than old style) |
| Capacity of Water Jacket & Hose | 5 quarts |
| Fan, O.D. Diameter | 14″ |
| Fan, Number of Blades | 4 |
| Fan Speed | 1.45 : 1 of engine |
| Fan Belt Type | Flat endless |
| Radiator Tubes, Number of | 98 |
| Radiator Fins, Number of | 109 |
| Hose Connections, Number of | 2 |
Electrical Equipment
| Ignition Type | High tension jump-spark |
| Magneto Type | Flywheel, 16 magnets, 16 coils, 25 turns on each |
| Coil Units | Transforms 8–30 volt input into 8,000–30,000 volt secondary |
| Spark Plugs | Champion, ½″ |
| Starter Engagement | Screw-type Bendix |
| Starter Source of Current | Storage battery |
| Starter Torque | 14 to 16 lb |
| Generator Drive | Gear |
| Generator Speed | 1½ : 1 of engine |
| Battery Make | Ford or Exide |
| Battery Capacity | 80 hours |
| Charging Rate | 10–12 amperes |
| Battery Plates, No. of | 13 |
| Battery Cells, No. of | 3 |
| Headlight Type | New Ford “H” |
| Headlight Bulb | 21 candle-power, gas-filled, double filament |
| Headlight Lens Diameter | 8½″ to 8 7/16″ |
| Tail Lamp Bulb | 3 c.p. |
| Horn Type | Vibrator |
Clutch
| Type | Multiple steel disc, operating in oil |
| Clutch Spring Tension | 90 lb |
| Clutch Pressure in High Gear | 324 lb |
| Large Discs, No. of | 13 |
| Small Discs, No. of | 12 |
Transmission
| Type | Special Ford Planetary |
| Speeds | 2 forward, 1 reverse |
| Driven Gear, Teeth | 27 |
| Driven Triple Gear, Teeth | 27 |
| Reverse Drum Gear, Teeth | 30 |
| Reverse Triple Gear, Teeth | 24 |
| Low Drum Gear, Teeth | 21 |
| Low Triple Gear, Teeth | 33 |
Gear Ratios — High Gear
| Model T Standard | 3.63 : 1 |
| Mountain (“Special High”) | 4 : 1 |
Rear Axle
| Type | Live |
| Gears, Type | Straight bevel |
| Lubricant | Heavy semi-fluid oil (A-1) |
| Lubricant Quantity | 1½ lb |
Front Axle
| Material | Ford alloy steel forging |
| Construction | I-beam |
| Tensile Strength | 125,000 to 145,000 lb / sq. in. |
| Tilt of Axle | 5½° |
Suspension — Front Springs
| Type | Transverse semi-elliptic |
| Leaves | 8 |
Suspension — Rear Springs
| Type | Transverse semi-elliptic |
| Spring Length | 43½″ |
| Spring Width | 2″ |
| No. of Leaves | 8 (Fordor and Tudor: 9) |
Steering
| Type | Planetary |
| Steering Wheel Diameter | 17″ |
Brakes — Hand (Emergency)
| Location | Rear wheels |
| Drum Diameter | 11″ |
| Drum Width | 1 5/8″ |
Brakes — Foot (Service)
| Location | Transmission |
| Lining Length | 23 7/16″ to 23½″ |
| Lining Width | 1 11/16″ |
| Lining Material | Cotton |
Lubrication
| Motor and Transmission | Constant level circulating splash |
| Capacity | 1 gal. light engine oil |
| Rear Axle Lubricant | A-1, heavy fluid or semi-fluid oil |
| Oiling Points and Grease Cups, No. of | 30 |
Road Wheels & Tyres
| Rim Make | Hayes, Kelsey or Ford |
| Tire Makes | U.S., Firestone, Goodyear, Goodrich, Miller, Mason |
| Balloon Tires | 29″ × 4.40″ front and rear |
Dimensions
| Wheelbase | 100″ |
| Tread (all Ford cars and trucks) | 56″ |
| Turning Circle | 38′ 6″ |
| Turning Radius | 19′ 3″ |
| Road Clearance | 10¼″ |
Instrument Board
| Material | Pressed steel |
| Finish | Baked enamel |
| Equipment | Light switch, ignition switch (battery and magneto), ammeter, carburetor choke rod |
Chassis Equipment
| Standard | Front fenders, head lamps, tail light, horn, jack, tire pump, keys, set of tools |
| Miscellaneous (all models) | Front mat, tonneau mat, jack, tire pump, keys, bag of tools (monkey wrench, end wrench, pliers, spark plug wrench, hub cap wrench, screwdriver on end of pliers, tire irons) |
Shipping & Road Weight
Add 65 lb to the shipping weight to obtain road weight — covers 5 gal. of gas, 1 gal. of oil, and 3½ gal. of water.
| Model T Chassis (Starter) | 1262 lb |
| Touring Car | 1728 lb |
| Roadster | 1645 lb |
| Coupe | 1851 lb |
| Sedan, 2-door (Tudor) | 1961 lb |
| Sedan, 4-door (Fordor) | 1994 lb |
| Ton Truck Chassis, Non-Starter | 1477 lb |
| Ton Truck Chassis, Starter | 1577 lb |
Finish & Upholstery
All models have baked enamel (450°F) finish on fenders, splash pans, radiator shells and small body parts.
| Touring (5-pass) & Roadster (2-pass) Finish | Gunmetal Blue or Phoenix Brown, 4 coats |
| Touring & Roadster Upholstery | Black artificial leather, pebble grain |
| Coupe (2-pass) & Sedan Tudor (5-pass) Finish | Fawn Gray, Highland Green or Royal Maroon, 6 coats |
| Coupe & Tudor Upholstery | Rich dark green wool fabric, carpets and silk curtains to match |
| Sedan Fordor (5-pass) Finish | Fawn Gray, Highland Green or Royal Maroon, 6 coats |
| Fordor Upholstery | Rich dark brown wool fabric, carpets and silk curtains to match |
Engine Speed & Gear Ratio Data
The standard Ford rear axle ratio is 3.63 to 1 (or 4 to 1 with optional mountain gears used in Coupes and Sedans in mountainous regions). With the standard 30-inch tires (94.25-inch rolling circumference), the rear wheels turn 672.3 times per mile.
| Gear Ratio, high speed (std / mountain) | 3.63 : 1 / 4 : 1 |
| Gear Ratio, low speed | 9.98 : 1 / 10.997 : 1 |
| Gear Ratio, reverse | 14.52 : 1 / 15.999 : 1 |
| Engine revolutions per mile, high speed | 2440 / 2689 |
| Engine revolutions per mile, low speed | 6709 / 7393 |
| Engine revolutions per mile, reverse | 9761 / 10755 |
| Ratio of crankshaft to driveshaft, low speed | 2.75 : 1 / 3.03 : 1 |
| Ratio of crankshaft to driveshaft, reverse | 4 : 1 / 4 : 1 |