Tech

Technical Information (2001)

Important information about Goodyear Racing Tires

Suggestic fitting advice and screwing procedure for Goodyear Drag Racing Tyres

Use of 18" V-8Star Tires on "Tri-Oval" Lausitzring

Für die rechte Fahrzeugseite dürfen bis auf weiteres ausschliesslich Goodyear Oval-Hinterreifen der Code-Nr. D-6562 ( Vorderachse ) und D-6564 ( Hinterachse ) verwendet werden.

All Goodyear Eagle radial tire production intended for competition are checked frequently to assure necessary and expected durability performance. This dynamic high speed testing is done at conditions designed to exceed the duty cycle the tire is likely to be exposed to on track and has provided considerable input into the minimum inflation pressures published by Goodyear. As speeds and aerodynamic downforce continue to increase, inflation pressures must also increase to ensure adequate load carrying capability exists. These minimum inflations are intended to provide a safe operating pressure for a normal range of chassis setups and are track specific. In addition to the lab testing used to help determine minimum pressures, extensive simulations encompassing load, speed, camber and slip angle also provide important data that is considered. Please note that all published minimum inflations are "cold". "Hot" pressure buildups are expected and should NEVER be bled from the tire between practice runs.

Deviation below minimum inflations can result in tire durability problems. Under-inflation can lead to a fatigue-related failure of the tire due to vertical and lateral over-deflection over the course of a fuel run and will typically result in a rapid inflation loss due to tire cord breakage in the sidewall. In addition to the potential for over-deflection, under-inflation will create high stress zones at the inside (cambered) shoulder of the tire due to elevated footprint unit pressures in this localized area of the tread surface. This is particularly critical on the right side position since they are the most highly loaded tires. The resulting failure mode will be a belt edge separation and tread area damage at the inside shoulder. Often, a noticeable vibration will be felt immediately before a rapid air loss occurs.

Excessive right front camber can also create an overly severe operating condition that may result in reduced levels of tire performance at the very least and, in a worst case scenario, create a strong potential for belt edge damage and air loss. Uneven distribution of unit pressure within the tire footprint caused by excessive camber will create high shoulder temperatures and uneven wear rates across the tread surface. Both of these conditions can be expected to contribute to an abnormally high rate of performance degradation or "giveup" over a fuel run. It is critical that individual teams understand and quantify the dynamic cambers that their setup choices create. Significant and often underestimated camber gains are a likely consequence of the "soft spring revolution" and must be added to initial static settings when determining a total dynamic camber angle. Body roll, chassis stiffness, shocks and sway bar choices will also affect dynamic camber and must be considered as setup decisions are made. Soft spring strategies and the associated high levels of suspension travel have also had a significant effect on dynamic straightaway camber, resulting in a constant unrelieved camber angle that can present a very challenging operation condition for the tire.

Based on high speed lab testing, force and moment evaluations and computer modeling simulations, Goodyear Racing recommends a maximum static right side cambers listed above be used with the radial tire line. It is unlikely that camber beyond this will yield additional grip but will significantly increase the risk of creating some or all of the previously described concerns. Keep in mind that the TOTAL DYNAMIC CAMBER MAXIMUM should not exceed -3.0 Degrees on the right side. 

PUBLISHED MINIMUM COLD INFLATIONS ARE STRICT REQUIREMENTS ESTABLISHED TO PREVENT TIRE OVER-DEFLECTION AND THE DAMAGE THAT CAN RESULT. DO NOT USE LOWER THAN MINIMUM INFLATIONS.