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Break-In Oil (SAE 30)

Designed for High-Performance and Racing Engines

Amsoil SAE-30 break-in motor oilAMSOIL Break-In Oil is an SAE 30 viscosity grade oil formulated without friction modifiers to allow for quick and efficient piston ring seating in new and rebuilt high-performance and racing engines. It contains zinc and phosphorus anti-wear additives to protect cam lobes, lifters and rockers during the critical break-in period when wear rates are highest, while its increased film strength protects rod and main bearings from damage. AMSOIL Break-In Oil is designed to increase compression, horsepower and torque for maximum engine performance.

Quickly Seats Rings
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, however, the oil must allow the correct level of "controlled wear" to occur between the cylinder wall/ring interface while maintaining wear protec­ tion 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).

Cylinder walls after break-in period

Kinematic Viscosity @ 100°C, cSt (ASTM D-445) 11.4
Kinematic Viscosity @ 40°C e, cSt (ASTM D-445) 91.6
Viscosity Index (ASTM D-2270) 112
Flash Point °C (°F) (ASTM D-92) 236(457)
Fire Point °C (°F) (ASTM D-92) 254(489)
Pour Point °C (°F) (ASTM D-97) -36(-32)
Four-Ball Wear (ASTM D-4172)
Para 1 (40 kg, 75°e, 1200 rpm, 1 hr), Scar, mm
Total Base Number 6.6
High-Temperature/High-Shear Viscosity
(ASTM D-5481 @ 150 o e, 1.0 x 106 S1), cP
Falex Procedure B (ASTM 0-3233) (failure load, Ibf.) >3500

Protects Critical Parts from Wear
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 phospho­ rus (ZOOP) additives designed to provide the anti-wear protection required during this critical period.

Increased Film Strength
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.

AMSOIL Break-In Oil is designed to effectively break in high­ performance and racing engines requiring SAE 30 oil, helping maximize compression, horsepower and torque.

The engine builder's or manufacturer's break-in recommenda­ tions should be followed if available. Break-in period should not exceed 1,000 miles. 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 measure­ ments over time. Break-in duration will vary between engines. Afterwards, drain and fill the engine with an AMSOIL high­ performance synthetic oil that meets builder or manufacturer specifications.

Oil residue before and after seals starting to seat