What Are the Tune-Up Specs for a Dodge 318?by John Stevens J.D.
Dodge first equipped the 318 small-block V-8 in the middle of the 1967 production year. However, the engine was essentially the same as the earlier 273 engine, but with a slightly larger bore. Although the 318 was never considered a high-performance engine, its durability made it a popular engine selection over the base model six-cylinder engines. As with all engines, the 318 does require a periodic tune-up. Fortunately, doing so is fairly straightforward -- provided that the engine's specifications are adhered to carefully.
The 318 was equipped with type N14Y spark plugs. The spark plug gap was .035 inches.
The distance between the tip of the distributor's ignition points at their extreme open position was .017 inches. Dwell angle was between 28 and 33 degrees.
Proper ignition timing was 5 degrees after top dead center if equipped with a manual transmission and 2.5 degrees after top dead center if equipped with an automatic transmission. Note that the distributor's vacuum hose must the disconnected from the distributor and plugged so that idle speed is not affected.
Hot Idle Speed
The engine's idle speed must be adjusted after the engine has reached its normal temperature and with the air conditioning compressor operating. The idle speed was 650 rpm with a manual transmission and 600 rpm with an automatic transmission.
Cylinder compression must be relatively uniform among all eight cylinders and within a range of 120 and 160 lbs.
Fuel Pump Pressure
In working condition, the fuel pump will provide between 5 and 7 lbs. of pressure to the carburetor.
- "Motor's Auto Repair Manual"; Ralph Ritchen; 1968