3 Litre Engine Specifications & Misc Info
Type 60^ SOHC (Per Bank)
Number of Cylinders 6
Bore 91.1mm (3.59 Inch's)
Stroke 76mm (2.99 Inch's)
Compression Ratio 8.85:1
Displacement 3.0 Liters (181 Cu. In.)  (2,972 cc)
Firing Order 1-2-3-4-5-6
Basic Ignition Timing 12°BTDC +/- 2°700 RPM
Valve Timing
      Intake - Open 19^BTDC
      Intake - Closed 57^ABDC
     Exhaust - Open 57^ BBDC
     Exhaust - Closed 19^ ATDC
Idle 850-1050 RPM


Description Standard Dimension Service Limit
Compression Pressure 178 psi @ 250 RPM
Maximum Variation Between Cylinders 1.0kg/cm2 (14 PSI) 25%
Manifold vacuum  520 mmHg (20 in.Hg.)
Valve Clearance - Hot Engine Hydraulic Lash Adjusters

Cylinder Head

   Flatness of Gasket Surface 0.05 mm (0.002 in.)
   Grinding Limit of Gasket Surface  0.2 mm (0.008 in.)


   Intake  0.10 mm (0.004 in.) 0.2 mm (0.0008 in.)
   Exhaust  0.15 mm (0.006 in.) 0.3 mm (0.001 in.)


Thickness of valve head (Margin)

   Intake  1.2 mm (.047 in.) 0.7 mm (.028 in.)
   Exhaust  2.0 mm (.079 in.) 1.5 mm (.059 in.)

Valve stem to valve guide clearance

   Intake 0.03-0.06 mm (.0012-.0024 in.) 0.10 mm (.0039 in.)
   Exhaust  0.05-0.09 mm (.0020-.0035 in.) 0.15 mm (.0059 in.)

Face angle 45°- 45.5°

Valve length

   Intake  103.0 mm (4.055 in.)
   Exhaust  102.7 mm (4.043 in.)

Stem O.D.

   Intake  7.960-7.975 mm (.3134-.3140 in.)
   Exhaust  7.930-7.950 mm (.3122-.3130 in.)

Valve guide Length

   Intake 44 mm (1.73 in.)
   Exhaust  48 mm (1.89 in.)
  OD 13.055 to 13.065mm (0.514 to 0.5143 in.)
   ID 8.000 to 8.018mm (0.314 to 0.315 in.)
      Service sizes: 0.05 mm (.002 in.) Oversize

0.25 mm (.010 in.) Oversize

0.50 mm (.020 in.) Oversize

Valve seat

   Width of seat contact  0.9 - 1.3 mm (.035 - .051 in.)
   Seat angle  44°- 44.5°
0.2mm (0.078 in.)

Valve spring

   Free length  50.5 mm (1.988 in.) 49.5 mm (1.949 in.)
   Load 329 N (74 lbs.) at installed height
    installed height  40.4 mm (1.591 in.) 41.4 mm (1.630 in.)
   Out of squareness  Less than 2°

Rocker Arm

    Rocker arm I.D.  19 mm (.75 in.)
   Clearance (Rocker arm to shaft)  0.01-0.04 mm (.0004-.0016 in.) 0.10 mm (0039 in.)
   Rocker arm shaft O.D. 18.9 mm (.744 in.)
Rocker arm shaft spring free length

   Intake 55.2 mm (2.173 in.)
   Exhaust  55.2 mm (2.173 in.)


Description  Standard Dimension Service Limit

   O.D.  91.08 to 91.10mm (3.585 to 3.586 in.)
   Clearance  0.02 - 0.04 mm (.0008 - .0016 in.)

Ring groove width

   No. 1  1.51 - 1.53 mm (.0594 to .0602 in.)
   No. 2  1.51-1.53 mm (.0594 to .0602 in.)
   Oil  4.010-4.035 mm (.1579 to .1589 in.)
       Service sizes  0.25 mm (.010 in.) Oversize

0.50 mm (.020 in.) Oversize

0.75 mm (.30 in.) Oversize

1.00 mm (.039 in.) Oversize

Side clearance

   No. 1  0.03-0.09 mm (.0012-.0035 in.) 0.1 mm (.004 in.)
   No. 2  0.02-0.06 mm (.0008-.0024 in.) 0.1 mm (.004 in.)
End gap

    No. 1  0.30-0.45 mm (.0118-.0177 in.) 0.8 mm (031 in.)
    No. 2  0.25-0.40 mm (.0098-.0157 in.) 0.8 mm (031 in.)
   Oil ring side rail  0.20 - 0.70 mm (.0079 - .0276 in.) 1.0 mm (.039 in.)
      Service sizes 0.25 mm (.010 in.) Oversize

0.50 mm (.020 in.) Oversize

0.75 mm (.030 in.) Oversize

1.00 mm (.039 in.) Oversize


   Length Center to Center 140.9 - 141.0 mm (5.547 - 5.551 in.)
   Bend  0.05 mm (.0020 in.) or less
   Twist  0.05 mm (.0020 in.) or less
   Connecting rod side clearance  0.10-0.25( .0039-.0098 in.) 0.4 mm (.016 in.)
   Piston pin press-in load  7,500-17,500 N (1,686-3,934 lbs.)


   End play  0.05-0.25 mm (.0020-.0098 in.) 0.3 mm (012 in.)
   Journal O.D.  59.980 - 60.0 mm (2.361 - 2.362 in.)
   Pin O.D.  49.980 - 50.0 mm (1.968 - 1.969 in.)
   Out-of-roundness of journal and pin Less than 0.03 mm (.0012 in.)
   Taper of journal and pin  Less than 0.005 mm (.0002 in.)
   Bearing Oil Clearance 0.016 to 0.046mm (.0008-.0019 in) 0.1 mm (.004 in.)


   Cylinder bore 91.1 mm (3.587 in.)
   Out of-roundness and taper of bore  Less than 0.02 mm (.0008 in.)
   Flatness of gasket surface  Less than 0.05 mm (.0020 in.) 0.10 mm (.0039 in.)
   Combined Limit Block/Head  0.20 mm (.008 in.)


   Relief Valve Opening Pressure 5.0 to 6.0 kg/cm2 (71.45 to 85.75 psi)
   Body Clearance 0.10 to 0.18mm (.004 to .007 in.) .3 (.001 in.)
   Side Clearance 0.04 to 0.09mm (0.03 to 0.07 in.) 0.15mm (.006 in.)
   Inner Rotor to Case 0.03 to .07mm (.001 to .002 in.) 0.15mm (.006 in.)

The cylinder block is a light weight design created by reducing the thickness in many parts and a short 10 mm (3/8") block skirt.  High rigidity is provided with ribs cast in the outer wall, a full length water jacket, and a monoblock or beam type, main bearing cap.  The single unit (4 bearing)  cap is designed to control vibration of the cylinder block partition walls.

A six throw, five weight crankshaft is supported by 4 main bearings with number 3 being the thrust bearing.  The six separate connecting rod throws (pins) reduce torque fluctuations while a torsional (vibration) damper is used to control torsion caused vibration of the crankshaft.  Rubber lipped seals are used at front and rear.  The front seal is retained in the oil pump case and the rear is retained in a block-mounted housing.

Are aluminum alloy with a steel strut, short height, and thin wall so as to be autothermic and light weight.  The piston head with valve recesses, in combination with the cylinder head, forms a compact spherical head with clearance for total valve lift with pistons at top dead center.  The piston skirt, top, and second ring lands are finished with curvilinear tapered roughness for oil retention and high resistance to scuffing.  Piston pins, press fitted into place, join the pistons to the connecting rods.

Cylinder Head
The alloy cylinder heads feature cross-flow type intake and exhaust ports.  Valve guides and inserts are hardened cast iron.  Valves of heat resistance steel are arranged in a "V" with each camshaft to center.  To improve combustion speed the chambers are compact spherical design with a squish area of approximately 30% of the piston top area.  The cylinder heads are common to either cylinder bank by reversing the direction of installation.

Two overhead camshafts provide valve actuation, one front (radiator side of cylinder bank) and one rear.  The front camshaft is provided with a distributor drive and is longer, and while both camshafts are supported by four bearing journals, thrust for the front camshaft is taken at journal two and the rear at journal three.  Front and rear camshaft driving sprockets are interchangeable.  The sprockets (and the engine water pump) are driven by a single notch timing belt.

Rocker Arm Shafts
The shafts are retained by the camshaft bearing journal caps.  Four shafts are used, one for each intake and exhaust rocker arm assembly on each cylinder head.  The hollow shafts provide a duct for lubricating oil flow from the cylinder head to the valve mechanisms.

Rocker Arms
Are of light weight die-cast with hardened alloy inserts operating against the camshaft.  The valve actuating end of the rocker arms are machined to retain hydraulic lash adjusters, eliminating valve lash adjustment.

Are made of heat resistant steel and further treated to resist heat.

Valve Springs
Are especially designed to be short.  The valve spring wire cross-section os "oval" shaped and provides the same spring tension as longer springs.  Valve spring retainers, locks, and seals are conventional.

Intake Manifold
The aluminum alloy manifold is a cross type with long runners to improve inertia.  The runners, attaching below at the cylinder head, also attach above (and support) an air plenum.  The air plenum chamber absorbs air pusations created during the suction phase of each cylinder.

Exhaust Manifolds
Both front "log" type (radiator side) and rear "fan" type are of ductile cast iron.  Exhaust gasses, collected from the front cylinder bank, leave the front manifold through an "end" outlet and are fed through an upper crossover tube to a fourth runner of the rear manifold.  The collected exhaust from both manifolds are combined, and exit to the exhaust pipe through an articulated joint.

Engine Lubrication
System is a full flow filtration, pressure feed type.  To provide a compact engine structure, the oil  pump is mounted within a case (or front cover) also containing the (timing belt side) crankshaft seal.  The pump inner rotor is installed on and rotates with the crankshaft.  The engine oil pan contains a baffle plate to control oil level fluctuation during engine operation. *  Source:  Chrysler Factory Service Manuals.

Home | My '78 Horizon | My '88 Caravan | My '93 Caravan | Repair/Upgrade | Links | 3.0L Mopar Registry | Disclaimer

Visitors Since 06/19/2002  Last Updated 11/28/2002