A. Depends on the size and weight of the vehicle. The following is a general guideline for starting pressures:

• 33x16, 33x17, 32x14.5: 6psi
• 28x9, 29x9 and 30x9: 12psi
• 25x9, 26x9: RWD 10psi, FWD 6psi
• Free Rolling recommended tire air pressure: 40psi

Adjust the tire air pressure up or down in 1/8 to 1/4 PSI increments to achieve the desired results. Use as much tire air pressure as possible for the track condition without causing the tire to slip. As a general rule, lower the pressure to increase traction, and increase the pressure to improve reaction time, stability, and rolling resistance. We do not recommend using tire air pressure of less than 5psi, as stability will be severely compromised.

A radial passenger tire design for the street has an "inner liner" to hold air for daily use. A bias drag slick is designed without such inner liner to reduce weight; which means that for bias drag slicks, tire air pressure must be checked before each pass.