SPECIFICATIONS
Back to Tech Tips Page
  CRANKSHAFT
Weight 28 lbs
Main Bearings: 1.624" Dia
Crank Pins: 1.499" Dia
Crank Pin Taper and Roundness: .0005" to .001"
Rear Flange Thickness: 3/8"
End Clearance: .004" to 007"
Main Bearing Clearance: .001"
Crankshaft Straightness: .0005"
Main Bearing Car Torque:80-100lbs

CYLINDER BLOCK
Cylinder Bore: 3.875" to 3.876"
Valve Guide Bore: .594" to .595"
Flatness On Top block: .003"
Cylinder Bore Perpendicular to Top: .001" to .002"

DRIVESHAFT
Spline Inner Dia: .901" to .911"
Spline Outer Dia: 1.090" to 1.091"
Pinion Bearing Torque: 15 to 20 inch lbs

ENGINE
Rated Horse Power: 24.03 SAE
Brake Horse Power: 40 HP
Firing order 1-2-4-3
Compression Ratio:4.22:1
Piston Displacement:200.5 Cu. In.
Bore:3.876"
Stroke:4.250"

CONNECTING RODS
Weight:1lb, 6Oz
Balance Weight:552 gms +/-1 gmm, crank end
198 gmms +/- 1 gmm, pin end
Crankshaft Bearing:1-1/2" Dia.
Piston Pin Bearing:1" Dia.
Bearing Side Clearance:.008" to .012"
Piston Pin Clearance:.005"
Crankshaft Clearance:.001"
Bearing Cap Bolt torque:40 - 50 lbs
Assembled with Oil Dippers Facing Camshaft.

FLYWHEEL
Weight:63lbs, 4oz.
Balance Within .15 In/oz
Flywheel Bolt Torque:65 Ft/lbs
Clutch Mounting surface and disc surface
must run true to crankshaft within .005" TIR.
Clutch mounting shoulder diameter must be
concentric with crankshaft flange diameter within .005" TIR
Pilot bearing GMN6203DV

LUBRICATION
Oil Pump Type:Gear
Pump capacity:9 Pints/min @ 1300 RPM
Pump Gear Teeth To Housing Clearance:.001" to .002"
Cover To Gear Face Clearance:.001" to .002"
Drive Gear to Camshaft Gear Clearance:.003" to .005"

CYLINDER HEAD
Compression ratio :1928:4.3:1 1929/31:#4.22:1

IGNITION
Rotor Rotation:counter clockwise
Point Gap:.016" to .020"
Condenser Capacity:.20 to .25 MFD
Spark Plug:Champion 3X, 7/8-18 Thread
Spark Plug Gap:.035"
Spark Manual Advance:20 Deg
Rotor Air Gap:.025"

COOLING SYSTEM
Water Pump Shaft:5/8" Dia
Water Pump Shaft end Play:.006 to .010"
Radiator Hoses:1928/29 - upper 2" Dia., 6-1/4" Long
1930-31 - upper 2" Dia., 8" Long
Lower ( two pieces ) 1-3/4" Dia, 2-3/4" Long
System Capacity:3 Galls
Radiator Capacity:1-1/2 Galls.
Radiator Flow 38 GPM

GAS TANK
Capacity:1928/29, 10 Galls: 1930/31, 11 Gallons

PISTONS
Displacement:200.5 cu. Inches
Weight:1 lb. 1-7/8 oz (476.8 gms)
Variance in weight:+/- gms
Diameter:3.8745" (Bore 3.875)
Variation in Piston Compression Height:.003" to .005"
Piston Pin Bushing:ID .992", to OD. 1.0675"
Pin Fit In Rod Bushing:.003" MAX
Pin fit In Piston:.002", to .005"
Piston Fit In Cylinder:, .002"
Ring Clearance in Grove:.001" to .002"
Ring End Gap:TOP- .012":to .015":Middle- .010 to .012":Bottom- .008 to .010"

VALVES
Lift:.287" with .015" Clearance
Seat Angle:45 Deg
Seat Width:3/32"
Stem Dia:.311"
Valve Length:5.677"
Head Diameter:1.537"
Valve Opening Dia:1-3/8"
Port Dia:1-3/8"
Valve Clearance:Exhaust .002":Intake .001" to .0015"
Lifter Clearance:Exhaust .015"
Intake .013"
Valve Guides:ID .3135":OD. .5938"
Valve Spring:OD 1.022":Valve Timing Intake opens 7-1/2 deg BTDC
Intake Closes 48-1/2 deg A BDC
Exhaust Opens 51-1/2 deg Before BDC
Exhaust Closes 401/2 ATDC

CAMSHAFT
Shaft Dia:7/8"
Bearing Dia:1.560"
Block Bore Dia:1.561"
Bearing Clearance (MAX):.003"
Cam Lift:.303"
Duration:236 Deg
Timing gear Cover Spring: Tension 35 lbs.
Timing Gear Backlash:.003 to .005" (max .009)
Camshaft Straightness:.0005" to .001"

SPRINGS
Front, Free Length:(10 Leaf) 30-5/8" to 30-13/16"
Rear, Free length:Tudor/Fordor 38-7/8" to 39"
Phaeton, Roadster, Coupe 39-1/8" to 39-1/2"

STEERING
Turning Radius:17 Ft.
Gear Ratio:1928/29 11-1/4:1:1930/31 13;1
Steering Wheel Dia:1928/29 17-1/2":1930/31 17"
Sector Shaft Bearing Clearance:.001" to .0015"
Bearings:7 Tooth T83:2- Tooth Timken 3571

TRANSMISSION
Gear Ratio:High 1;1 Second 6.9:1 Low 8.75:1
Bearings:Main Shaft Front Ball--1208
Main Shaft Rear Ball--1306
Counter Shaft Short --Bower J241256
Counter Shaft Long--Bower J241246
Pilot Bearing--SKF 2RSJ

RADIATOR
Tubes:1928 Round, 1/4 Dia
Number of Tubes:94 in 4 rows
1929 Round, 1/4 Dia
Number of Tubes:100 in 4 rows, or 87 in 5 rows
Tubes 1930/31 Flat, 5/32 x 1/2"
Number of Tubes:102 in 3 rows
Flow Rate:38 GPM

CLUTCH
Pressure Plate Weight:15 lbs
Clutch Disc Weight:2-1/2" lbs
Clutch Pressure:1100 lbs
Foot Pedal Pressure:30 lbs.
Clutch Dia:9", Thickness:9/64"
Clutch pedal Clearance ( Free Play ):1".
Clutch Release Bearing:Bower 2065

CARBURETTOR
Throat Size:1"
Float Level:1" from Float Ring to Machine Surface
Main Jet:No 63 Drill Bit
Cap Jet:No 63 Drill Bit
Comp Jet:No 65 Drill Bit
Idle Jet:No 75 Drill Bit