General Regulations for Series run on Circuits / Automobile Sport Part 2 – Technical Regulations by Porsche Motorsport North America (v6 / 03.26.2021) Porsche Sprint Challenge North America Foreword: United States Auto Club, hereinafter called USAC, is hosting the Porsche Sprint Challenge North America for 2021. Organization: USAC Porsche Sprint Challenge North America 4910 W. 16th Street Speedway IN 46224 USA Table of Contents General Regulations for ........................................................................................................................................................... 1 Series run on Circuits / Automobile Sport ......................................................................................................................... 1 3. Eligible Cars ...................................................................................................................................................................... 5 4. Driver Safety Equipment ............................................................................................................................................... 5 5. Technical Inspection ...................................................................................................................................................... 7 6. Mandatory Safety Requirements .............................................................................................................................. 10 7. Eligible Engines & ECUs .............................................................................................................................................. 13 8. Drivetrain ......................................................................................................................................................................... 14 9. Suspension ...................................................................................................................................................................... 15 10. Dash and Data Collection ............................................................................................................................................ 17 11. Fuel .................................................................................................................................................................................... 17 12. Windows .......................................................................................................................................................................... 18 13. Brakes and Brake Pads ................................................................................................................................................ 18 14. Weight .............................................................................................................................................................................. 19 15. Wheels ............................................................................................................................................................................. 19 16. Tires .................................................................................................................................................................................. 19 17. Miscellaneous ................................................................................................................................................................. 20 18. APPENDIX 1A - Platinum Class GT3 Cup 991.2 .................................................................................................. 22 19. APPENDIX 1B - Gold Class GT3 Cup 991.1 .......................................................................................................... 23 20. APPENDIX 2A - Silver Class 718 GT4 Cayman (Type 982) ............................................................................. 24 21. APPENDIX 2B- Silver Class 718 GT4 Cayman (Type 981) .............................................................................. 28 22. APPENDIX 3 - Minimum Ground Clearance GT3 Cup ........................................................................................ 32 23. APPENDIX 4 - Minimum Ground Clearance GT4 ................................................................................................. 33 24. APPENDIX 5 - Differential Graphics Platinum/Gold ........................................................................................... 36 25. APPENDIX 6 - OE Recaro Seat Padding Graphic ALL Classes ......................................................................... 37 26. APPENDIX 7 - Window Net Detail All Classes ...................................................................................................... 37 27. APPENDIX 8 - Approved Ballast Location All Classes ........................................................................................ 38 28. APPENDIX 9 - Mandatory Radio Frequencies ....................................................................................................... 39 29. APPENDIX 10 - Equivalence Formula ..................................................................................................................... 40 30. APPENDIX 11 - Identification of original Porsche windscreens ...................................................................... 41 31. APPENDIX 12 – Tires ................................................................................................................................................... 42 32. APPENDIX 13 – Timing Transponder Position ..................................................................................................... 45 33. APPENDIX 14 – Underbody cover (991) ............................................................................................................... 46 Page 2 of 46 03.26.21 v 06.0 2.1 Series Technical Regulations Summary of the eligible groups/classes The Porsche Sprint Challenge North America is an official Porsche AG one-make Series with multiple group/class classifications. Only cars of the type/model: • Porsche 911 GT3 Cup, type 991 II (a special series produced by Porsche AG), of the model year 2017- 2019 • Porsche 911 GT3 Cup, type 991 I (a special series produced by Porsche AG), of the model year 2014- 2016 • Porsche 718 Cayman GT4 Clubsport (Trackday, Competition or MR) of the model year 2019 – 2020 • Porsche 981 Cayman GT4 Clubsport of the model year 2016 which fully comply with these Regulations as well as the appropriate Porsche Technical Manual are eligible to participate. A change of cars must be applied for in writing by the competitor and must be approved in written form by the Stewards prior to the change. The decision to approve a change of car is at the absolute discretion of the Stewards. Where the Stewards accept such an application, that acceptance may be given subject to specific conditions. Where the replacement of a car is accepted after Qualifying it will normally be on condition that the car starts the race from the back of the grid. Cars submitted by Porsche AG or USAC may deviate from the Technical Regulations for development purposes. The deviations shall be referred for approval by USAC before the car is used and shall not involve any safety-critical modifications. 2.2 Principles of the Technical Regulations In accordance with: ☒ Art. 251 and 277 (Group EII-SH) of Appendix J (FIA ISC) ☒ These Technical Regulations ☒ Technical manuals of the eligible cars ☒ Technical information of Porsche Motorsport North America ☒ Software information of Porsche Motorsport North America ☒ Spare parts catalogues of the eligible cars Should there be any discrepancy between the provisions of these Technical Regulations and any relevant Technical Manual, Technical Information, Software Information or Parts Catalogue, then these Technical Regulations will take precedence. Any requirements specified in a Technical Manual, Technical Information, Software Information and/or Parts Catalogue may be updated by Porsche Motorsport North America. For Software Information, only the latest version is valid but Setups (based on the latest version) may be varied within the parameters allowed by Porsche Motorsport North America. Any requirements may be varied for any specific event by USAC at that event. Page 3 of 46 03.26.21 v 06.0 2.3 Porsche Technical Manuals and Updates Teams must subscribe to and always refer to PMRSI - Porsche Motorsport Racecar Service Information for up-to- date information about your racecar. https://motorsport.porsche.com/ 2.4 General/preamble Everything that is not expressly permitted in these Regulations is prohibited. Permitted modifications must not result in any illegal modifications or infringements of the Regulations. All cars must be original Porsche Cup or Clubsport cars as delivered by Porsche and the VIN number must reflect this. No aftermarket conversions to cars are permitted. Except where specifically permitted herein, there are no changes permitted to the cars from their original specifications. There must be no welding, cutting, machining, drilling, acid dipping or other chemical treatment of the car to change its mechanical properties. Any change to the car that is not specifically permitted in the Technical Regulations is expressly prohibited. Except where specified, all parts must be stock, original equipment (OE) and in the original location as delivered. This means that they must be the Porsche designated parts that were as the car was delivered and be listed