EP 10-2009 34-50_Layout 1 10/8/09 1:25 PM Page 36 Engine Oils BY LAKE SPEED JR. More has changed in oil than ZDDP up of deposits also helps protect catalytic What exactly is synthetic oil? content in the last 10 years. The levels of converters from “Zinc”, so modern To answer that question you have to ask detergents have also increased, and both passenger car oil formulas now feature another question. What is in a motor are contributing factors in the flat-tappet increased levels of detergents. You’ve oil? Motor oil is a blend of performance camshaft problems seen in the engine probably seen the TV ads that promote additives in a base oil. The additives building industry over the last 4 to 5 oils that clean your engine. Those are enhance the performance of the lubricant years. high detergent oils, and they are great beyond the performance of the base oil. The oil additive Zinc Dialkyl for modern passenger car engines. They Typical additives are detergents, anti- Dithiophosphate (commonly referred to are not great for restoration and street wear agents, friction modifiers, viscosity as “Zinc” or ZDDP) provides anti-wear rod engines. modifiers and many other chemicals that protection for engines — especially flat The balance of “Zinc” vs. Detergents help the lubricant meet the performance tappet camshafts. has changed in the last several years in requirements of an application. The base “Zinc” works because it is a polar an effort to protect catalytic converters. oil is the other part of a motor oil, and molecule (it has a positive charge), so the This shift in the balance away from the base oil makes up the majority of the “Zinc” molecule is attracted to steel. “Zinc” and towards detergents has had finished motor oil. Base oils typically Under heat and load, the “Zinc” a negative impact on flat tappet come from 3 sources: refined crude oil, molecule reacts with the steel and creates camshaft life. synthetic base stocks, or vegetable oils. a film. The film created by the “Zinc” Why is this important? In the old The vast majority of motor oils use prevents metal to metal contact. That is days, engine builders used SAE 30 grade, refined crude oil as the base oil. These how “Zinc” works to protect your non-detergent oil to break-in an engine. oils are commonly referred to as mineral engine. The break-in period is the most critical oils or petroleum oils. Refined crude oils Detergents are also polar molecules, time in the life of an engine. The non- provide good lubricity at a lower cost, and the detergent is designed to prevent detergent oil was effective at establishing but refined crude oils have a strong build up of deposits in the engine. a “Zinc” anti-wear film in the engine tendency to oxidize at high temperatures As a result, both the “Zinc” and during break-in because the “Zinc” did (AKA breaking down). Because detergents compete against each other not have to compete against the petroleum oils come out of the ground, for the metal surface. detergent. As a result, the engine had they contain many imperfections. These The reduction in “Zinc” in modern better access to the “Zinc” it needed imperfections lead to breakdown at high passenger car grade oils relates to when we needed it the most. Modern temperatures. When an oil catalytic converter life. The same coating engines feature roller follower overhead “breaksdown” it can create deposits in effect that “Zinc” provides to protect cam designs that reduce weight and the engine. A synthetic oil is a man made your camshaft also damages your sliding friction. As a result, these copy of petroleum oil without any of the catalytic converter. To extend the life of valvetrains don’t need higher levels of “imperfections” that lead to catalytic converters, “Zinc” content has “Zinc”, but a Big Block Chevy has push “breakdown”. As a result, synthetic oils been reduced. rods, a flat tappet camshaft and big steel can safely handle much higher operating At the same time, detergent levels valves. These older engines feature temperatures compared to petroleum have increased to provide better engine increased sliding friction and weight. oils. Because synthetic base oils are made cleanliness, longer catalytic converter life These engines need increased levels of in a controlled environment, they are and extended oil drain intervals. “Zinc”. The oils originally developed for 100% pure, and that also allows The use of Exhaust Gas Recirculation Big Block Chevys used less detergent and synthetic oils to flow better at low valves cleans up the emissions of an more “Zinc” than modern engine oils. temperatures. Synthetic oils can reduce engine, but the use of EGR valves To protect a flat-tappet camshaft, Cold Start Wear by up to 70% increases the need for detergents due to you need to properly break-in the compared to Petroleum oils. Since Hot increased temperatures and recirculated camshaft with a high “Zinc” oil and Rods and Restoration cars spend a lot of combustion by-products. avoid high detergent oils for both break- time in the garage, synthetic oils provide Detergents’ ability to prevent build in and service fill. continued on page 39 36 OCT-DEC 2009 engine professional EP 10-2009 34-50_Layout 1 10/8/09 1:26 PM Page 39 ENGINE OILS BY LAKE SPEED JR. excellent flow when the engine is oil. The API ratings tell you about the started after being in the garage for additive package in the oil. Since a time. 1992 when the American Petroleum Institute (API) introduced the SM – Is it safe to use synthetic oil in a GF1 standard, the “Zinc” content in flat-tappet engine? passenger car grades of motor oil has After a proper break-in period on been limited. The level of “Zinc” in petroleum oil, a synthetic oil with the passenger car oils was reduced again proper balance of “Zinc” and in 1996 to 1,000 ppm under API SJ – detergents will provide greater GF2 standards. In 2001, API SL – protection than a petroleum oil. GF3 standards restricted “Zinc” Over the years, synthetic oils have content to 850 ppm, and that is when been criticized for their performance cams started to fail. When the API in older style engines. The problem went to the current standard (SM – has been the use of oils designed for GF4), camshaft failures skyrocketed. modern passenger cars in older style In addition to the reduction in engines. The synthetic base oil is “Zinc”, detergent levels increased as superior to conventional petroleum each new API standard took effect. base oils, but the additive packages in An API SJ rated oil contained half the modern passenger car formulations amount of detergent that an API SM will not provide the levels of oil contains. The increase in protection a flat-tappet camshaft detergents and reduction in “Zinc” needs. The problem is not synthetic have been a double whammy for flat oil. The problem is using modern oils tappet camshafts. in older style engines. You shouldn’t Because NASCAR forces the use a racing oil in a daily driver, so Sprint Cup Series teams to run flat- why would you use a modern daily tappet camshafts, Joe Gibbs Racing driver oil in a restoration car? developed high “Zinc” oils to Is it safe to use synthetic oils in properly break-in our flat tappet transmissions and rear ends? camshafts. The Joe Gibbs BR Break- If the oil has the proper additives for In oil is the number 1 selling break-in the materials, it is safe to use oil in the world. The Joe Gibbs BR synthetic gear, transmission and Break-In oil features a low detergent power steering fluid in a street rod or and high “Zinc” formula that allows restoration car. the “Zinc” additive to create a protective film in your engine. Joe What is an API rating? How is it different Gibbs also offers a Hot Rod oil that from an oil’s viscosity rating? also features a high “Zinc” content The viscosity ratings of the oil with a normal detergent level just for describe the cold start and high non-emission controlled vehicles temperature flow rates of the oil. A (street rods, restorations, etc…). The 0W-30 flows better at start up than a Joe Gibbs Hot Rod oil also features a 10W-30. The number before the “W” US military grade rust and corrosion is the cold start viscosity, so the lower inhibitor that protects your engine the number, the easier it is to start the while the car is in storage for the engine. The higher the number, the winter. Conventional oils will run more power it takes to turn the down into the oil pan after extended motor over when you hit the ignition. periods of storage – leaving the The number after the “W” is the engine vulnerable to rust and high temperature flow rate of the oil. corrosion. The Joe Gibbs Hot Rod oil For example, while a 0W-30 flows creates a tenacious oil film that will better at start up than a 10W-30, cling to the part no matter how long both oils flow like a SAE 30 grade at it sits in storage. This oil films high temperature (212F). The higher prevents air and moisture from the number after the “W”, the attacking your engine.I heavier the oil is at higher temperature. A 5W-40 is a heavier oil Lake Speed Jr. from Joe Gibbs Racing is the son at high temperature than a 5W-30, so of Lake Speed Sr., who raced in NASCAR from SAE viscosity ratings only tell you 1980 to 1998.