After a frustrating weekend fixing power steering issues at a recent American Muscle Car Masters event, I decided it was time to identify some of the key issues that can be faced when repairing or specifying a power steering system for a race car. The goal for me was to put together the best system for my car without too much gold plating or unnecessary bells and whistles; a GUD Power Steering System....

Here are 5 key things to think about when putting together the race car steering parts for your grassroots race cars, the same info applies to fixing existing issues.

1.Spindle Arm Length

• On a road race car, the distance between the center of lower ball joint and the center of the steering arm mounting point should be equal left to right. On a road race stock car that may have previously been raced on an oval this should be checked carefully. Road racing parts such as these Howe Road Racing Spindles and Spindle Slugs are designed specifically for road racing.
• When evaluating circle track parts on a dirt track car or an asphalt oval car often the left spindle arm is run slightly shorter than the right arm to increase toe on the inside wheel when turning left which increases the Ackermann Steering Effect.

2.Rack & Servo Selection

• Integral or remote servo, This Rack by Sweet Manufacturing comes with a directly coupled servo whereas This Rack is set up for a separate servo.
• Servo assist stiffness or feel typically describes the diameter of the servo torq rod. The smaller the rod diameter, the lighter the feel or more power assist.
• Rack Speed is the distance the rack will travel when the steering wheel is rotated one complete turn. The higher the speed of the rack, the more force it takes to turn it.
• Rack center distance is the distance between the center points of the rack ends, this ultimately can affect Bump Steer so comparing to control arm pick up points and geometry is important to minimize the effect.

3.Steering Wheel Diameter is often overlooked but obviously the key item that joins the nut behind the wheel to the rest of the system. The basic way to think about wheel diameter is bigger diameter, less force required by the driver to turn the wheels. If you’re thinking about stock car road racing parts like we do, or for circle track parts, you may consider up to 15” diameter like This Wheel from MPI when running tires with large, sticky contact patches such as those on most oval track stock cars and road race stock cars.

4.Pump Drive Speed is a vital factor to ensure the power steering pump manufacturer’s rated RPM range is maintained. The math here is: Pump RPM= Crank Pully Diameter/Pump Pulley Diameter*Engine RPM.

5.Pump flow valve selection can be adjusted to further refine the feel of the power steering system by increasing or decreasing the flow from the pump. This Flow Assist Valve Kit is a worthwhile addition to your race box and contains a set of five flow valves used to fine tune the output from the power steering pump. They are easily changeable race weekend parts to give more or less power assist driver feel.