AMSOIL SAE 30 Break-In Oil

Friction-modifier-free formula helps rings seat properly for maximum compression and reduced blow-by. Excellent film strength and proprietary anti-wear additive package help ensure cams and bearings are protected during break-in. Delivers competition-quality engine preparation.

Break-in duration will vary between engines, but should not exceed 1,000 miles (1,600 km). If available, the engine builder’s or manufacturer’s break-in recommendations should be followed. After completing break in, drain and fill the engine with a high-performance AMSOIL synthetic oil that meets builder or manufacturer specifications.

The primary goal during engine break-in is to seat the rings against the cylinder wall. Properly seated rings increase compression, resulting in maximum horsepower; they reduce oil consumption and prevent hot combustion gases from entering the crankcase. To achieve this, the oil must allow the correct level of “controlled wear” to occur between the cylinder wall/ring interface while maintaining wear protection on other critical engine parts. Insufficient break-in leaves behind peaks on the cylinder wall that prevent the rings from seating. The deeper valleys, meanwhile, allow excess oil to collect and burn during combustion, increasing oil consumption. Too much wear results in cylinder glazing due to peaks “rolling over” into the valleys and preventing oil from collecting and adequately lubricating the cylinder wall. AMSOIL Break-In Oil’s friction-modifier-free formula allows the sharp peaks on newly honed cylinder walls (fig. 1) to partially flatten. The result produces more surface area for rings to seat against, allowing formation of a dynamic seal that increases compression, horsepower and torque (fig. 2).

AMSOIL Break-In Oil is designed to deliver maximum compression, horsepower and torque by providing quick and efficient piston ring seating in new and rebuilt high-performance and racing engines. It is formulated with zinc and phosphorus anti-wear additives to protect cam lobes, lifters and rockers during the critical break-in period when wear rates are highest. Its increased film strength also protects rods and main bearings from damage.

New flat-tappet camshafts and lifters are not seasoned or broken in and must be heat-cycled to achieve proper hardness. During the break-in period, these components are susceptible to accelerated wear because they are splash-lubricated, unlike other areas of the engine that are pressure lubricated. AMSOIL Break-In Oil contains high levels of zinc and phosphorus (ZDDP) additives designed to provide the anti-wear protection required during this critical period.

High-performance and racing engines often use aftermarket parts designed to increase torque and horsepower. The added stress can rupture the oil film responsible for preventing harmful metal-to-metal contact on rod and main bearings. The base oils in AMSOIL Break-In Oil provide increased film strength to protect bearings from wear.

When the engine is new, the exhaust ports will have a large area of oil residue (Fig. 3). As the rings begin to seat, less oil is passed and the oil residue area begins to shrink (Fig. 4). When the rings are fully seated and have formed a tight seal against the cylinder walls, no oil residue will be evident. Other common methods to determine if rings have seated include performing a leak-down test or horsepower measurements over time.