PHA events are operated under the PHA Supplementary Regulations:

2025 PHA Supplementary Regulations

Driver and Car Safety Rules for all classes are defined in the PHA Supplementary Regulations Document linked above.

Car Preparation Rules are defined in the following documents:

• SCCA GCR Classes are defined in the current SCCA General Competiton Ruleboook.  All classes listed in the current GCR (National and Regional) will be accommodated.
• PHA Supplemental Classes are defined in the PHA Supplementary Regulations Document linked above.
• Solo and Time Trial Derived Classes are also defined in the PHA Supplemental Regulations Document linked above.

NOTE on the  Solo and Time Trial Derived Classes category:

• • For Solo derived cars, refer to the SCCA National Solo Rules for Car Preparation, and the PHA Supplemental Regulations for Safety.
  • For Time Trial derived cars, refer to the SCCA National Time Trial Rules (see Classing and Rules Menu) for Car Preparation, and the PHA Supplemental Regulations for Safety.
  • Some GCR derived cars can also run in these classes — see PHA Supps for list.  For these cars, refer to the current SCCA GCR for Car Preparation, and the PHA Supplemental Regulations for Safety.

NOTE on SCCA Time Trial Classes at some PHA track events:

For some of the PHA track events, the National SCCA Time Trials classes are  included as “Event Supplemental Classes”.  Refer to the event description for each event to determine if National TT classes are permitted.

In the case where National TT classes are listed as Event Supplemental Classes for a PHA event:  for TT classed cars, refer to the SCCA National Time Trial Rules for Car Preparation and Driver and Car Safety.   Note that for these events, a TT classed car that meets all of the PHA Driver and Car Safety requirements may compete in either the TT class, or in the appropriate Solo and Time Trial Derived class as defined in the PHA Supps.

New for 2025:

 A group of Solo and Time Trial Derived classes were introduced in 2025.  These classes are:  Sport Lite (SL), Sport (S), Super Sport (SS), Sport Max (SX), Sport Unlimited (SU), Modified (M), Super Modified (SM), and Outlaw (0).

With the introduction of these new classes, the SCCA Solo Street Modified (SM, SSM, SMF), the SCCA Solo Street Prepared Classes (SSP, ASP, BSP, CSP,  DSP,  ESP, FSP), and the PHA Supplemental Class Street Modified Extreme (SMX) have been retired.  Cars that previously ran in one of these classes will now run in one of the Solo and Time Trial Derived Classes.

Some production based and production silhouette based GCR classed cars are eligible to run in the new classes.   For example, cars in the GT3, GTL, STL, EP, FP and HP GCR classes can run in the new Modified (M) class  provided that they meet the other Modified class restrictions.  Or they can stay in their current GCR class.  See the PHA Supplemental Regulations Document for details on which GCR classes qualify and prep restrictions.

NOTE:  The PHA Supplemental Class Street Modified RWD (SMR) was retained by vote of the PHA membership.  This class is based on the Solo Street Modified Class, but is restricted to RWD cars.  See the PHA Supplemental Regulations Document for details on the SMR class.