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Signature Series Motor Oil Protects Engines From Low-Speed Pre-Ignition

SIGNATURE SERIES Protects Engines from Future Industry Problem

LSPI can destroy pistons and connecting rods, bringing an engine to a standstill in seconds. Original equipment manufacturers (OEMs) like General Motors (GM)* have addressed the issue by designing tests to gauge a motor oil’s ability to prevent these destructive events. Signature Series achieved 100 percent protection against LSPI1 in the industry-standard test.

OEMs have been aggressively downsizing engines to meet strict fuel economy and emissions standards while improving power and torque. Most new engines today use some combination of turbochargers, direct-fuel injection and variable valve timing to make more power than their larger counterparts while delivering improved fuel economy.

This scenario seems like all upside for drivers. But today’s smaller, hotter-running engines pose significant challenges to lubricants. The latest is a phenomenon called low-speed pre-ignition (LSPI), also known as “super knock,” which can destroy pistons and connecting rods.

What Is LSPI?

LSPI is another version of engine knock, which has been around since engines were invented. In this case, it occurs under low-speed, high-torque conditions in turbocharged gasoline direct-injected engines – like when you’re taking off from a stoplight. LSPI is the spontaneous ignition of the fuel/air mixture prior to spark-triggered ignition. This form of pre-ignition is more destructive than typical engine knock.

No Magic Bullet

Just as your engine relies on a balanced network of components to function, the motor oil needed to protect it requires additives with the right qualities at the right quantities. While adding more of one ingredient or reducing another seems simple enough, small composition changes can have big impacts. We were determined to find a solution to the LSPI problem without sacrificing the performance of Signature Series in any way.

GM LSPI Test

OEMs like GM have addressed the issue by designing tests to determine a motor oil’s ability to prevent LSPI. The GM LSPI Test records the number of peak pressure events during high-load operation in a turbocharged engine over a five-hour period. Passing the test is required to meet the GM dexos1® Gen 2 specification.

Perfect Score

We armed Signature Series with an advanced detergent system that protects against harmful deposits and LSPI. Signature Series Motor Oil achieved 100 percent protection against LSPI in the engine test required by the GM dexos1 Gen 2 specifications – zero occurrences were recorded throughout five consecutive tests.

API SN PLUS Specifications

API SN PLUS is a recently released specification that was requested by the automobile industry to protect passenger vehicles from LSPI. AMSOIL anticipated this change, and the current formulations of Signature Series, XL and OE synthetic motor oil all meet or exceed the specification. Look for updated product labels featuring the new API “donut” in the near future.

Your customers can be confident that AMSOIL synthetic motor oils protect their modern engines against LSPI, helping their vehicles deliver years of reliable service. For more information on the dangers of LSPI, visit www.amsoil.com/lspi.

 

Example of piston damage due to an LSPI event observed during the testing of a competitor’s motor oil. The red arrows indicate sections of the ring land that have broken away from the piston.

Achieved 100% Protection Against LSPI1

Is There Really an Advantage with Premium Gas?

OCTANE EXPLAINED: DOES PREMIUM, HIGH-OCTANE GAS BOOST PERFORMANCE?

Save yourself a lot of money and use the lowest rating suggested in your owners manual. Typically the only cars which need premium fuel are older high compression engines (pre 1980’s) and the ever popular turbocharged engines. I run premium in my Ford Transit with the Ecoboost Turbo as it is required. The added compression demands it to resiste pre-ignition (reducing knock) and I’ve even verified maximum mileage on Cenex 91 even over the OK’d 89, but on typical fuel injection cars over the past 25 years lower octane ratings are no issue at all  – Enjoy the article below…

Sioux Falls drivers – email me your favorite gas stop you get the best performance from and I’ll make a post listing any feedback we get. Thanks!! Email me at ches@syntheticwarehouse.com

A recent AAA report found that American motorists wasted $2.1 billion in the last year buying premium gasoline for engines designed to run on regular gas.

The reasons why are likely due to the following misconceptions about premium gas:

  • Contains higher energy content (increasing power and fuel economy)
  • Formulated with higher-quality additives (increasing engine cleanliness)

What is Premium Gas?

When motorists see premium 91-octane gas at the pump, they may assume it contains higher energy content compared to regular 87-octane gas. After all, “high-octane” is often synonymous with increased power and performance. The 91-octane gas should, they think, provide improved fuel economy and power.

In fact, octane has nothing to do with energy content or quality – it’s a measurement of the gasoline’s ability to resist engine knock. Higher octane denotes greater knock control.

What is Engine Knock?

Octane neededOn an engine’s intake stroke, the piston travels down the cylinder, allowing air/ fuel to fill the available space. Assume the cylinder holds 900cc when the piston is at bottom dead center. The piston then travels up the cylinder, compressing the fuel/air in preparation for combustion. Assume cylinder volume is reduced to 100cc when the piston is at top dead center. The relationship between the two volumes is known as the compression ratio. In this case, 900:100 is reduced to 9:1. The compression ratio indicates cylinder pressure, and more pressure equals more power and greater efficiency. That’s why high-performance cars and heavy-duty diesels typically have higher compression ratios than standard cars or trucks.

While higher compression seems like all up-side, it can invite negative consequences. Compression heats the fuel/air mixture, allowing it to burn more efficiently. If compressed too much, gasoline can ignite too early, causing uncontrolled and early ignition. This leads to a knocking or pinging sound, robs the engine of power and can lead to engine damage. Typically, the engine’s computer will detect engine knock and adjust timing and the air/ fuel ratio accordingly. Although this protects the engine from damage, it can substantially reduce engine performance and efficiency.

Most high-compression gas engines require use of premium gas to better resist engine knock and prevent the computer from detuning the engine to protect against knock-related damage. Using premium gas in a clean, mechanically sound engine not designed to use it, though, provides no benefit.

In engines with carbon buildup on pistons or in the combustion chamber, however, premium gas can provide some benefit. Deposits can reduce cylinder volume at top dead center, effectively increasing the compression ratio. This alone can lead to engine knock. The deposits can also become hot spots that preignite the mixture, leading to engine knock.

In these cases, a higher octane fuel helps resist engine knock and allows the engine to operate closer to its normal conditions rather than detuning to prevent engine knock.

For best performance, use the fuel recommended in your vehicle owner’s manual.

Higher Octane Doesn’t Mean Higher Quality

The other popular misconception is that premium gas contains a higher concentration of cleaning agents and other performance-improving additives.

While many formulators market a highquality premium gasoline, such as Shell* V-Power* Nitro+ or ExxonMobil* Synergy*, the premium gasoline at your local filling station may not be formulated to improve performance in any aspect other than octane rating. Quality can vary from brand to brand and station to station.

This is why we sell AMSOIL P.i.® (API)  for cars and trucks and AMSOIL Quickshot® (AQS) for smaller engines. They provide excellent detergency to help clean dirty injectors and carburetors for maximum fuel economy and operability. Once you understand the truth about premium gas, these additives will better assist in overall performance thus giving better peace of mind and benefits you’re seeking.