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Downsized gasoline engines, coupled with gasoline direct injection (GDI) and turbocharging, have provided an effective means to meet both emissions standards and customers’ drivability expectations. As a result, these engines have become more and more common in the passenger vehicle marketplace over the past 10 years. To maximize fuel economy, these engines are commonly calibrated to operate at low speeds and high engine loads – well into the traditional ‘knock-limited’ region. Advanced engine controls and GDI have effectively suppressed knock and allowed the engines to operate in this high efficiency region more often than was historically possible. Unfortunately, many of these downsized, boosted engines have experienced a different type of uncontrolled combustion. This combustion occurs when the engine is operating under high load and low speed conditions and has been named Low Speed Pre-Ignition (LSPI). LSPI has shown to be very damaging to engine hardware.

In a two-stroke engine, carbon is a natural by-product of incomplete combustion. Fuel and oil quality vary leading to various degrees of carbon deposit build up on critical engine parts over time. If the carbon deposits are left on engine components and allowed to accumulate, it can lead to reduced horsepower, reduced fuel economy, increased emissions, and in the worst case the deposits can cause engine damage. A novel two-stroke engine oil was developed specifically to remove these deposits, restore the operating efficiency, and potentially lengthen the useful life of the two-stroke engine. In order to prove the restorative ability of this novel technology, dynamometer tests and field trials were conducted. In the dynamometer portion, the oil was tested in two of the standard TC-W3® certification tests for marine engine oils. The first was the OMC 40HP and the second was the OMC 70HP test.

The new American Petroleum Institute (API) categories for passenger car motor oils have focused on improving fuel economy and reducing emissions. This has resulted in more fuel efficient oils being developed by lowering the viscometrics and by adding friction modifiers. The emissions reductions have resulted from lowering the percent phosphorus (%P) in the engine oils because phosphorus has been found to poison the catalyst in the catalytic converter. When friction modifiers were introduced, researchers from four Japanese motorcycle manufacturers published the results of their studies (SAE 961217) which indicated that low friction oil can cause too much slippage in starter motor clutches, one-way limited slip clutches, and wet multi-plate clutches. In that same study they reported that engine manufacturers use 10W-30 grade oil to develop new engine technology, and gear pitting was observed with oils of viscosity grades lower than 10W-30 in all four manufacturers' motorcycle engines.