By Titus Bloom

Cutaway showing Spool Valve

If the spool valve encounters friction when it moves, it slows the response of the steering. To prevent the spool valve from sticking or cocking in its bore, KRC hones this oil passageway twice

It’s common knowledge that the entry of one foreign particle in the power steering system can damage the pump. Even if the pump survives the ordeal the refuse will momentarily zap engine power each time it passes through the rotor housing easily consuming 10hp, according to KRC’s new and unique steering pump tester.

Ken Roper, KRC Power

Ken Roper, KRC Power

“This custom-made machine records horsepower, flow and pressure and checks the data every 1,000rpm from 1,000 to 10,000rpm,” says KRC chief Ken Roper. “It even produces graphs and retrieves information we didn’t request! But perhaps its most valuable attribute is that it reveals information we never knew before, like power consumption under load, and it validates everything.”

Though the average Sportsman race team may not be too concerned if a steering pump consumes 3hp or 6hp, others like NASCAR teams cannot afford any power-robbing deficiencies and would eagerly welcome even a ½ hp advantage.

What caused recent power steering system failures?

Recently new short track oval race chassis have suffered a spate of power steering failures. The troubles were traced to the pressure relief valve (spool valve) in the power steering pump. Apparently, galling had caused it to jam in the bore.

“For years,” says Roper, “production road car pumps have been modified and offered for use on new race car chassis. As you’d expect, they are inexpensive and most of the time they perform adequately. But they have always been a marginal proposition for race cars as most of their internals are uncoated. Without exception, any friction in the pressure relief valve area slows steering response.”

To maintain the valve’s proper function KRC recommends hard-anodizing and honing the bore to 0.0002in and coating the valve with electroless nickel. This nickel-phosphorous process applies deposits 0.030in thick to the relief valve, which are then ground to provide a perfectly round shape. To their new Pro series power steering pumps these are the standards KRC applies.

KRC Power Steering
Kennesaw, Georgia
(770) 422-5135