Tech Talk Article 5
"Reher's Rules:
How To Keep Your Engine Alive"
by David Reher
Page 1

        You don't have to be a cardiologist like my fellow back-page columnist Dr. Torstveit to appreciate the importance of blood in the human body.  I've watched enough episodes of "ER" and "Chicago Hope" to know that even a momentary interruption in the flow of blood to the brain can cause permanent damage.

        At the risk of repeating a cliché, I'll state categorically that oil is the lifeblood of an engine.  The consequences of erratic oil delivery in a racing engine can be just as traumatic as the medical emergencies on television shows - but instead of comas and strokes, the likely results are broken connecting rods and catastrophic engine failures.

        I estimate that nine out of ten connecting rod failures are not the fault of the connecting rod.  Almost invariably, a broken rod is the result of a spun bearing -and the bearing failure is usually the result of an oil system problem.  If an autopsy of a blown engine reveals even the hint of a blackened crankshaft rod journal, that's strong evidence that a spun bearing was responsible, not the connecting rod.

        When drag racers think about oiling systems, they usually look for ways to increase power by reducing windage and parasitic 

losses.  That approach may be valid if you're contending for the Pro Stock championship, but it's risky business for weekend warriors, bracket racers, and Super eliminator competitors.  Reher's first rule of racing is that reliability is more important than horsepower when you have to pay your own engine repair bills.

        I should point out the important distinction between wet-sump and dry-sump oil systems.  With a wet-sump system, an engine's entire oil supply is contained within the oil pan; with a dry-sump system, the oil is stored in an external tank.  This simple difference in how the two systems manage their respective oil reservoirs has huge implications for racers.

        A wet-sump system has the advantages of simplicity, low cost, and light weight.  That's why virtually every production engine in the world uses wet-sump lubrication.  A dry-sump system is more complicated, more expensive, and heavier than a wet-sump - but it offers the important benefit of continuous lubrication under all conditions and the promise of increased power through reduced windage.

        When you consider cost and complexity, a wet-sump oil system is the logical choice for 

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