"Regular oils" are mineral-based products refined from crude oil taken from the ground. Over the past 20 years these lubricants have been refined even further, particularly in the area of viscosity enhancers. This means modern oils flow better over a range of temperatures. This, in combination with engines that sport tighter clearances and better machining, allow for the use of thin oils that both reduce friction and improve fuel efficiency. For instance, in the world of racing, very few teams are going to be using motor oil with single rated viscosity. Racers not only want efficient operation and greater power, they want the best lubrication of engine parts as quickly as possible. (Start-ups deliver high engine wear, so you want an oil that gets to work quickly.)
"Synthetic oils", which have been around since the 1970s, have the same natural ingredients as "regular oils" but they are distilled in a chemical plant where the concept of refining goes techno-geek. Try wrapping your head around the concept of “synthesized-hydrocarbon molecular chains” and base fluids including “polyalphaolefin, synthetic esters, and alkylated aromatics.” What the heck do all these terms mean? In plain english, they are the engineered basis for the synthetic oil qualities listed below.
Synthetic oils:
are all season and have multi-viscosity properties, some flowing as much as seven times faster than regular oil.can stand extremes of engine temperature (some above 400°F) more efficiently.can boost horsepower more effectively than thinner regular oils.can be used for as much as 10,000 miles before requiring an oil change.contain fewer contaminants like sulfur, wax, and other elements that contribute to sludge build-up.
Of course, synthetic oils are more expensive and there are some things they don’t do, including:
eliminate the need for oil changes.or eliminate engine wear.
The major advantage of synthetic oils is superior lubrication that significantly reduces engine wear over the long term.
For regular drivers and performance car enthusiasts, there’s a place for both types of oil. Conventional wisdom suggests that you should use “regular” oil while breaking in an engine. At this phase of an engine’s life, you want some wear to make sure all the components get properly smoothed down. (On the other hand, there are plenty of performance cars that come from the factory using synthetic oil.) Depending on who you ask, this breaking-in period can be as short as 500 or as long as 5,000 miles. At whatever point you choose, the switch from regular oil to synthetic oil is intended to then slow engine wear down as much as possible. (And you don’t want to mix regular and synthetic as that’s a great recipe for sludge.) At the racing level, of course, a team is going to test various oils, determine what horsepower gain is returned, gauge the viscosity and temperature tolerances, and in short, make a science out of oil choice versus engine benefit.
As you can see, there are virtues to both types of engine oil. Anything you put in your engine or any modification you make to your vehicle, whether it's a racer or the family car, has to be looked at in terms of the goal you're seeking to achieve. Without question, the chemical composition of synthetic oils have a quality and uniformity at the molecular level that just isn't found in conventional, "regular" oils. Synthetic oils will continue to be fine-tuned in the laboratory to give even higher levels of performance and benefit. As we ask more of our engines, not only in terms of output but in the areas of clean and efficient operation, no one can afford to rule out synthetic oils as a viable option, on or off the track. Like everything about automobiles, lubrication techniques are evolving rapidly and the days of indiscriminately telling the guy at the gas station to "just add a quart" are definitely over.
