Chrysler 318 (5.2 L) Magnum V8

Chrysler 318 (5.2 L) Magnum V8The Chrysler/Dodge 318 Magnum is a 5.2 l (5,211 cc, 318.0 natural aspirated V8 90° four-stroke gasoline engine from Chrysler LA/Magnum-family. This engine was manufactured from 1992 up to 2003.

The Chrysler 318 Magnum features a cast-iron block and two cast-iron heads with a single camshaft (OHV) and two valves per cylinder (16 valves in total). The Chrysler 3.9L Magnum engine is equipped with a multi-point fuel injection system and a mechanically timed electrical ignition system with an ignition coil and mechanical distributor.

The compression ratio rating is 9.1:1. Cylinder bore and the piston stroke are 99.3 mm (3.91 in) and 84.0 mm (3.31 in), respectively. It produces 234 PS (172 kW; 230 HP) at 4,100 rpm of horsepower and 400 N·m (40.8 kg·m, 295 ft·lb) at 3,000 rpm of maximum torque.

General information

Engine Specifications
Engine modelChrysler 5.2 L (318 cu in) Magnum
LayoutFour stroke, V8
Fuel typeGasoline (petrol)
Displacement5.2 L, 5,211 cc (318.0 cu in)
Fuel systemMulti-point Fuel Injection
Power adderNone
Power output234 PS (172 kW; 230 HP) at 4,100 rpm
Torque output400 N·m (40.8 kg·m, 295 ft·lb) at 3,000 rpm
Firing order1-8-4-3-6-5-7-2
Dimensions (L x W x H):

Cylinder block

The 318 Magnum engine has a cast-iron block with a five-bearings crankshaft supported system. The cylinder bore is 99.3 mm (3.91 in), piston stroke is 84.0 mm (3.31 in) and the compression ratio rating is 9.1:1. This motor has aluminum alloy pistons with two compression and one oil control rings, forged steel connecting rods, and nodular iron crankshaft. The crankshaft main journal diameter is 63.5 mm (2.5 in) and the crankpin diameter is 53.0 mm (2.08 in).

Cylinder block
Cylinder block alloyCast-iron
Compression ratio:9.1:1
Cylinder bore:99.3 mm (3.91 in)
Piston stroke:84.0 mm (3.31 in)
Number of piston rings (compression / oil):2/1
Number of main bearings:5
Cylinder inner diameter (standard):99.314-99.365 mm (3.91-3.912 in)
Piston skirt diameter (standard):
Piston pin outer diameter:24.996-25.001 mm (0.9841-0.9843 in)
Piston ring side clearance:Top0.038-0.076 mm (0.0015-0.003 in)
Second0.038-0.076 mm (0.0015-0.003 in)
Oil0.060-0.210 mm (0.0024-0.0083 in)
Piston ring end gap:Top0.254-0.508 mm (0.010-0.020 in)
Second0.254-0.508 mm (0.010-0.020 in)
Oil0.254-1.270 mm (0.010-0.050 in)
Connecting rod small end diameter:24.940-24.978 mm (0.9819-0.9834 in)
Crankshaft main journal diameter:63.487-63.513 mm (2.4995-2.5005 in)
Crankpin diameter:53.950-53.975 mm (2.124-2.125 in)

Main bearing beam bolts tightening procedure and torque specs:

  • 115 Nm; 11.5 kg·m; 85 ft·lb in two-three stages

After securing bearing cap bolts, make sure crankshaft turns smoothly by hand.

Connecting rod bearing bolts

  • 61 Nm; 6.0 kg·m; 45 ft·lb

Cylinder head

The cylinder heads are made of cats-iron. The engine has a single camshaft over-head valves. The camshaft is driven by a single timing chain. The intake valve diameter is 48.665 mm (1.916 in), the duration is 250° the exhaust valve diameter is 41.250 mm (1.624 in), the duration is 264°. The Chrysler 318 Magnum engine is equipped with hydraulic valve tappets.

Cylinder head
Block head alloyCast-iron
Valve Arrangement:OHV, chain drive
Head surface flatness
Valves:16 (2 valves per cylinder)
Intake valve timing250°
Exhaust valve timing:264°
Valve head diameter:INTAKE48.665 mm (1.9159 in)
EXHAUST41.250 mm (1.624 in)
Valve length:INTAKE124.280-125.92 mm (4.8929-4.9575 in)
EXHAUST124.64-125.27 mm (4.9071-4.9319 in)
Valve stem diameter:INTAKE7.899-7.925 mm (0.311-0.312 in)
EXHAUST7.899-7.925 mm (0.311-0.312 in)
Valve spring free length:49.962 mm (1.967 in)

Head tightening procedure and torque specs:

  • Step 1: 68 Nm; 6.8 kg·m; 50 ft·lb
  • Step 2: 143 Nm; 14.0 kg·m; 105 ft·lb

Cylinder head cover bolts

  • 11 Nm; 1.1 kg·m; 8.1 ft·lb

Maintenance data

Compression pressure
Standard689 kPa (100 psi)
Oil system
Recommended engine oilSAE: 10W-30
Oil type APIAPI: SH or SH/CD
Engine oil capacity (Refill capacity) With filter change 4.7 L (5.0 US. qt, 4.2 Imp. qt.)
Without filter change 4.3 L (4.6 US. qt, 3.8 Imp. qt.)
Oil pressure Idle speed: 41.4 kPA (6 psi)
3,000 rpm 207-551 kPA (30-80 psi)
Ignition system
Spark plugChampion RC12YC
Spark plug gap0.9 mm (0.0354 in)
Spark plug tightening torque41.0 N·m (4.2 kg·m, 30.2 ft·lb)

Vehicle applications

ModelYears Produced
Dodge Dakota1992–2000
Dodge Ram1992–2001
Dodge Durango1998–2000
Dodge Ramcharger1992–1993
Dodge Ram Van1992–2003
Jeep Grand Cherokee1993–1998
ATTENTION! Dear visitors, this site is not a trading platform, an official dealer or a spare parts supplier, so we do not have any price lists or spare parts catalogs. We are an information portal and provide the technical specifications of gasoline and diesel engines.

We try to use verified sources and official documentation, however, differences between sources or errors in entering information may occur. We do not provide advice on technical issues related to the engines operation or repair. We do not recommend using provided information for engines repairing engines or spare parts ordering, use only official service manuals and spare-parts catalogs.

Be the first to comment

Leave a Reply

Your email address will not be published.