1958 Dodge/Mopar 230 L6 Engine Specifications

Courtesy of Shannon Mafodda

Specifications for 1958 Coronet 6-Cylinder L-Head Engine
Type	L head Straight Six
Bore and stroke	3.25 x 4.63"
Piston Displacement (cu. Inch)	230.2
Taxable Horsepower (ama)	25.35
Compression Ratio	8.0 to 1
Compression Pressure (speed minimum 150 rpm, plugs removed, wide open throttle)	120 to 150 lbs
Maximum Brake horse power at 3600 rpm	123
Firing order	1-5-3-6-2-4

Camshaft
Drive	Chain
End Paly	.002-.006"
Radial Clearance	.001-.003""

Camshaft Journals
Diameter and Length	No.1 1.998-1.99 x 7/8"
	No.2 1.982-1.983 x 3/4"
	No.3 1.967-1.968 x 3/4"
	No.4 1.951-1.952 x 3/4"
	No.5 1.4355-1.4365 x 15/16"
Crankshaft
Type	Counter Balanced
Bearings	replaceable
End Play	.003-.007"
Radial Clearance	.0005-.0015"


Connecting Rods
Length (center to center)	7 13/16"
Diameter and Length	2 1/16 x 1"

Connecting Rod Bushing
Type	Bronze
Diameter and Length	55/64 x 1 1/8''

Pistons
Clearance (3/4 inch from bottom on thrust face)	.002 to .0012"
Weight (Standard through all oversize)	16 oz
Ring Groove Width (Compression)	.0169"
(oil)	.172"

Valves (intake)
Head Diameter	1 17/32"
Lift	23/64"
Stem Diameter	.340 to .341"
Stem to Guide Clearance	.001 to.003"

Valves (Exhaust)
Head Diameter	1 13/32"
Lift	23/64"
Stem Diameter	.340 to .341"
Stem to Guide Clearance	.003 to.005"


Distributor For 6 Cylinder

Model	IBR-4001
Rotation	Clockwise
Advance Control	Automatic
Point Gap	.018 to .022"
Breaker Arm Spring Tension	17 to 20
Contact Dwell (degrees)	39+/- 3 Deg

Automatic Advance curve (Distributor speed)

250 to 450	0 Deg
450	0 to 2 Deg
1150	5.5 to 7.5 Deg
1800	7.5 to 9.5 Deg

Vacuum Advance Curve
Manifold vacuum in inches of mercury
5.25 to 6.75	0 Deg
10	3.5 to 5.5 Deg
16	8.5 to 10.5 deg
Condenser Capacity (Microfarads)	.25 to .285
Timing Mark location (marks 1 deg apart)	Vibration Damper
Engine Idle Speed (RPM)	450 to 500
Firing Order	1-5-3-6-2-4

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