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The relationship between 76 Racing and NASCAR allowed 76 Lubricants Company to work closely with Richard Childress Racing (RCR) and The Lubrizol Corporation in the development of oil screening and analytical test procedures which permit rapid evaluation of potential top-tier NASCAR race oils. The oils were designed to meet the challenge of increasingly severe engine operating parameters. This paper will discuss dynamometer testing and how properties of the oil such as viscosity grade, base fluid, and additives affect engine durability in the dynamometer test program and performance at the track in NASCAR Winston Cup Racing. Areas of growing concern include the cam/lifter contact, ring/liner contact, wrist pin/pin bore and wrist pin bushing contacts. Racing lubricants must withstand these harsh conditions for periods of 3-4 hours of continuous running.

The need for special gasolines for racing has grown over the past 40+ years as engine technology has evolved and engine efficiency have improved. What started out as supplying service station gasoline to early stock car racing competitors in the National Association for Stock Car Automobile Racing, Inc. (NASCAR) has grown into supplying a specialized racing gasoline for the very sophisticated racing engines used in stock car racing as we know it today. In 1951 the Pure Oil Company, which merged with the Union Oil Company of California (now Unocal) in 1965, began supplying gasoline for stock car racing sanctioned by NASCAR in the southeastern United States. Today, Unocal continues to provide gasoline to NASCAR, but it is a significantly different product than in the 1950's. In the early years, compression ratios and horsepower output were relatively low (average of 7:1 and 101 for the 1951 model year) and octane demand was satisfied by service station gasoline.

Results from two separate emission test programs using a fifteen fuel test matrix in which ten key fuel properties were independently varied have shown that changes in gasoline distillation characteristics, olefin content and Reid vapor pressure (RVP) can produce major changes in total tailpipe exhaust emissions. All other variables examined, including oxygen content and aromatic content of the fuels, did not directly affect the tailpipe output of carbon monoxide, nitrogen oxides, or hydrocarbon emissions. From these results a generalized mathematical model was produced which predicts tailpipe emission changes from key fuel properties. The model was verified in a separate, 13 vehicle study.

The Coordinating Research Council, Inc. has studied the octane requirement increase (ORI) of cars and light duty trucks since 1971. This paper investigates ORI trends and influencing effects for over 600 1980 through 1988 model-year vehicles. An analysis of these vehicles shows them to have an average ORI of 3.8 (R+M)/2 measured with refinery-like fuels, and suggests the average ORI decreased from 1980 through 1986, followed by a possible, but statistically uncertain, increase starting in 1987 or 1988. A number of factors have contributed to lower ORI, including higher compression ratios, use of aluminum cylinder heads, multiport fuel injection, and three-way catalyst systems. SPARK KNOCK IS THE NOISE produced by the auto-ignition of the air-fuel mixture in the end gases of the spark-ignition engine.

In 1985 the U.S. Environmental Protection Agency instituted regulations which have ultimately limited the lead content of leaded gasolines to 0.1 grams of lead per gallon. There is currently very little test work on the potential for exhaust valve seat recession while running an engine with a cast iron head without hardened exhaust valve seats on gasoline at this lead level. Therefore, we have examined valve seat recession from low lead fuels. The test program described here evaluates test conditions and additives which can affect exhaust valve seat recession in mid-1960s vintage heads. Cylinder heads produced after the early 1970s had induction hardened exhaust valve seats and were not susceptible to exhaust valve seat recession. Specifically, tests were run in which lead, air/fuel ratio and engine hardware (valve rotators) were varied and evaluated for contribution to the valve recession process.

The Coordinating Research Council (CRC) conducted a program during the summer of 1972 to determine the decrease in octane number requirement with altitude for current model cars. The study was made because the engines in these cars run hotter and leaner than earlier models, no information was available on altitude corrections for unleaded fuels, and no adjustment was planned for the so-called 91 octane gasolines in the symbol system being developed by ASTM/SAE. Maximum octane number requirements were determined on thirty-nine 1971-1972 model cars, six 1967-1970 model cars, and four light-duty military trucks at sea level, 2000, and 4000 ft on three series of full-boiling range fuels and primary reference fuels. Results indicate that the decrease in octane number requirement per inch of mercury decrease (approximately per 1000 ft) is about two units for 1971-1972 cars and 1.5 units for the 1967-1970 cars and the four military trucks.