Scrub Radius...... Introduction

[Tony]

This topic definitely cannot be explained in one post so small informative increments will over time cover the whole picture.

 

Scrub Radius ( SR ) is the point that all the Geometrical angles at the front are placed. When a Geometry is measured the figures suggest an area within the radii and careful positions conclude all the forces to ensure the car performs as desired.... but what are these forces? and what do they look like?

 

 

This image displays three angles the other six would have made things even more complicated, we will work on them at a later date.

 

 

Nevertheless you can see these angles in 3D, we have 'Longitudinal, lateral and vertical' And the 'SR' is the recipient, ( triangulate)

 

The 'SR' is the contact area between the tyre and the road, these 'forces' need to be directed to specific areas of that patch...... To far to the outside with the Camber will make the car pull...... To far in will make the tyre wear, to much toe out will make the car bump steer and nervous, to little will make it lazy, both if incorrect will force the tyres to wear. The Castor will add/retract directional control, add/retract the Turing radii, all of this is the direct consequence of the positions within the 'SR' there are also indirect consequences....again this we will discuss later.

 

Add to this any modifications then calculating the placement of these three angles becomes a nightmare. But not impossible