1951 Chevrolet 235 Engine Specifications

General Specifications
Bore 3 9/16″
Stroke 3 15/16″
Displacement 235.5 ci
Compression 6.70 : 1
Max Brake Horsepower 105 @ 3600 RPM
Max Torque 193 Lbs.ft. @ 2000 RPM
Normal Oil Pressure 14 psi
Spark Plug Make AC 46-5
Spark Plug Gap .035″
Firing Order 153624
Engine Idle Speed 475 RPM
Oil Capacity 5 qts.
Ignition Timing Timing mark: steel ball on flywheel
Cylinder Head Torque 75 – 80 Lbs.ft.
Compression at Crank Speed 110 psi
Piston and Ring Specifications
Min. Ring Gap (Compression) .005″
Clearance in Groove (Compression) .0015″ – .0030″
Min. Ring Gap (Oil) .005″
Clearance in Groove (Oil) .0020″ – .0035″
Wristpin Diameter .8645″ – .8650″
Valve Specifications
Operating Clearance – Intake (w/ Standard Trans) .006″ Hot
Operating Clearance – Exhaust (w/ Standard Trans) .015″ Hot
Operating Clearance – Intake (w/ Powerglide) 0
Operating Clearance – Exhaust (w/ Powerglide) 0
Clearance for Timing Intake 0
Intake Valve Seat Angle 31°
Exhaust Valve Seat Angle 46°
Intake Valve Timing (w/ Standard Trans) Opens 1° after Top Dead Center
Exhaust Valve Timing (w/ Standard Trans) Closes 9° after Top Dead Center
Intake Valve Timing (w/ Powerglide) Opens 16° after Top Dead Center
Exhaust Valve Timing (w/ Powerglide) Closes 17.5° after Top Dead Center
Valve Spring Pressure (w/ Standard Trans) 125 lbs. @ 1.5″
Valve Spring Pressure (w/ Powerglide) 160 lbs. @ 1.5″
Valve Stem Clearance (Intake) .001″ – .003″
Valve Stem Clearance (Exhaust) .002″ – .004″
Main Engine Bearing Specifications
Journal Diameter (Front) 2.6835″ – 2.6845″
Journal Diameter (No. 2) 2.7145′ – 2.7155″
Journal Diameter (No. 3) 2.7455″ – 2.7465″
Journal Diameter (No. 4) 2.7765″ – 2.7775″
Bearing Clearance .0007″ – .0028″
Crankshaft End Play .003″ – .009″ (taken on No. 3 bearing)
Main Bolt Tension 100-110 Lbs.ft.
Connecting Rod Bearing Specifications
Journal Diameter 2.311″ – 2.312″
Bearing Clearance .0003″ – .0013″
Rod End Play .004″ – .012″
Rod Bolt Tension 35 – 45 Lbs.ft.
Delco-Remy Distributor Specifications
Distributor Part No. 1112362, 1112363
Rotation Direction Clockwise
Cam Angle 31° – 37°
Breaker Point Opening .022″
Condenser Capacity 18 – .23 Mfds.
Breaker Arm Spring Tension 17 – 21 Oz.
Centifugal Advance Start (1112362) 1.5° @ 350RPM
Centifugal Advance Full (1112362) 19° @ 1700RPM
Centifugal Advance Start (1112363) 1° @ 300RPM
Centifugal Advance Full (1112363) 16.5° @ 1850RPM
Vacuum Advance Start 7 – 8.5″ of vacuum
Vacuum Advance Full 16.5 – 18.5″ of vacuum
Max Vacuum Advance 10°
Delco-Remy Generator Specifications
Generator Part Number 1102749, 1102761
Output (1102749) 45 Amps @ 2400 RPM
Output (1102761) 36 Amps @ 2400 RPM
Brush Spring Tension 28 oz.
Field Current (6 or 12 volts) 1.75 – 1.9
Delco-Remy Starter Specifications
Starter Part Number 1107075
Bush Spring Tension 24 – 28 oz.
No Load Test 70 amps, 5.65 Volts @ 5500 RPM
Torque Test 550 Amps, 3.25 Volts, Torque: 11 Lbs.ft.

Comments (1)

  1. dave wooster

    3 years ago

    i have a 51 chevy 3sp on col at this time my trans is in need of maj overhall..i’m about ready for t5 trans and differant rear end,haven’t madeup mind ..on gear rato for rear end… any advice? love the info on this web site

Leave a Comment

Your email address will not be published. Required fields are marked *