Peachstate Region - Porsche Club of America
Peachstate Region
Porsche Club of America
Peachstate Region
Porsche Club of America
Peachstate Region Autocross Categories, Car Classes and Modification Rules

Last Updated: 05/17/2020, 18:11:15

Parade Competition Rules

Peachstate region activities are run under the Porsche Club of America Parade Competition Rules or PCR's.  Peachstate region autocross follows the Medium Region rules for our category and class structure. 

The classes are defined as follows:

Showroom Stock

Unmodified - as it left the dealer on the day it was originally delivered.  Some very minor modifications are allowed.

Production

This is for lightly modified Porsches.  Typically aftermarket wheels, an exhaust or air filters will put you in Production.  GT cars are often in Production even as they leave the dealer due to the Sport Cup 2 tires low treadwear rating.

Improved

This class is for more modified Porsches.  The allowed modifications in this class are more than Production, but less than Modified.

Modified

This class is for the most modified Porsches - virtually race cars.

Non-Porsche

Peachstate PCA welcomes our non-Porsche driving friends to participate in our Autocross series.  Non-Porsche cars run in the Non-Porsche (NP) classes.  NP is your car class, not your membership status for event fees.

- NPS: Non-Porsche Stock is for unmodified Non-Porsche cars

- NPM: Non-Porsche Modified is for modified Non-Porsche cars

Allowed Modifications

A-2.5.3. "Free" Modifications

Safety equipment is free in all classes except Showroom Stock, provided limits of any class category are met. Items considered free include harness bars, fire extinguishers, non-factory seat belts, race seats, window nets, head rests, cut-off switches, tow hooks, seat back braces and required mounts for any of the above. In Showroom Stock, attachments points or mounts for any of these items may be left in the automobile, but the actual device will not be allowed to remain or be used if it could be considered to provide the driver or the automobile any performance advantage.

A-2.5.4. Showroom Stock Modifications

This class is for cars that are unmodified and running tires with a treadwear rating greater than 180.  Unless otherwise specified in these rules, no alterations or modifications are allowed to these automobiles. 

Only original equipment manufacturer (OEM) wheels as originally specified and OEM tire sizes as originally provided and/or specified for each specific model year are permitted. All Showroom Stock class tires must have a tread wear rating of 180 or greater. Wear and tear items, excluding tires, must be comparable in construction and specifications to the originally supplied factory components. Adjustments are permitted provided no modifications and/or alterations are necessary to achieve the desired adjustment. Automobiles must run with their spare tire, jack, lug wrench, owner’s manual(s), tools, etc. Owner’s manual(s) will be used to help verify questionable equipment options and designated wheel/tire sizes.

No aftermarket equipment that might be reasonably perceived as performance affecting is permitted in these classes. Items included in this restriction include, but may not be limited to, aftermarket air filters, aftermarket exhaust systems, aerodynamic aids, computer chips, five/six point seatbelts, race seats, harness bars, roll bars, roll cages, etc

Cars delivered with less than 180 tread wear rating tires are automatically advanced to their respective production classes.

 

A-2.5.5. Production Modifications 

The Production category is for street automobiles altered beyond the Showroom Stock limit, GT cars and older Porsches. The following adjustments, alterations or modifications are allowed in the Production class automobiles plus what was allowed in Showroom Stock. Automobiles may be updated to another model provided all of the automobile is brought up to that models specifications.

A-2.5.5.1. Engine

(a) Air Cleaner: The air cleaner may be removed, modified or replaced with another type. Any modification may not conflict with other rules.

(b) Modified Ignition: Any modification is permitted, provided an original type distributor is used.

(c) Modified Carburetors: Any automobile originally carbureted may have any carburetor, provided the throttle bore and venturi dimensions are not changed from original specifications. Jet sizes may be changed. 911 models with mechanical fuel injection or Solex carburetors may change to replacement carburetors that have throttle bores no larger than 40mm. 914/912E models may be converted to carburetors with throttle bores no larger than 40mm.

(d) Fuel Injection: No substitution of performance affecting components for fuel injected automobiles is permitted. Any DME EPROM chip may be used except for those chips programmed to alter turbo boost. No modifications to the intake manifold are allowed.

(e) Wet Sump Modifications: If an automobile has a wet sump lubrication system, the sump may be modified to ensure a constant source of engine lubrication at the oil pickup tube. If an automobile has a dry sump lubrication system, no modifications are permitted.

(f) Modified Oil Cooler/Filter: The addition of any oil cooler and/or filter is permitted.

(g) Substituted Roller Bearing Cranks: For 356-based or Carrera 4-based engines, any roller bearing crank may be used. Plain bearing cranks may be substituted for roller bearing cranks. Counterbalanced cranks are permitted.

(h) Balanced Engine: Balancing of internal engine parts is permitted.

(i) Camshafts: The stock camshaft must be used.

(j) Exhaust Modifications: Alternate exhaust systems are permitted after the head(s) for automobiles with or without catalytic converters. Headers are permitted. A muffler is required. Air pumps may be removed.

(k) Air Conditioning: Removal is permitted provided original automobile may have been delivered without it.

(l) Overbore: Overbore is allowed up to 1.2mm (0.047”).

(m) Gasoline: Any grade of automotive gasoline available to the general public through normal retail service stations is permitted.

(n) Clutch: Any model clutch is allowed. Rubber center clutch discs may be replaced with spring discs. The flywheel and pre4ssure plate may be lightened.

(o) Velocity Stack: Velocity stacks may be added or modified.

(p) Compression Ratio: Engine compression ratio’s may be increased up to .5 points from U.S. production specifications.

(q) Fuel Pump: Fitting of an electric fuel pump is permitted.

(r) Chain Tensioners/Guards: Any chain tensioner or guards are permitted.

(s) Battery: Any battery may be used. Those automobiles delivered with two batteries may remove one.

A-2.5.5.2. Suspension

(a) Limited Suspension Adjustments: Any adjustment of the standard suspension components is permitted, provided no machining is required for the adjustment. Factory components must be used for mounting of struts and shock absorbers to the body.

(b) Alignment: Any adjustment may be made provided no other change is necessary to make the adjustment.

(c) Coil Springs/Torsion Bars: Any coil spring may be replaced by any other coil spring. Any torsion bar may be replaced by any other torsion bar as long as they are of the same type and mount in the same manner without modification to the chassis or suspension components.

(d) Shock Absorbers: Any shock absorber may be used provided it is not remotely adjustable.

(e) Adjustable spring perches are allowed.

(f) Sway Bars: Any anti-sway bar may be installed. Sway bar may not be adjustable from the cockpit.

(g) Rear Camber Compensation (356 Only): Any rear camber compensating device may be used.

(h) Bushings: Non-standard (non-elastic) suspension bushings may be used.

(i) Shock Tower Brace: A front and/or rear shock tower brace may be used in any automobile provided that: (1) it can be quickly and easily removed; it must be a bolt-in component. Any number of attachment points may be used; (2) all attachment points are within three inches of a vertical plane passing through the top center of the shock absorber.

(j) Spring Plates: Adjustable spring plates are permitted on any automobile not so equipped from the factory.

(k) Tie-Rod Ends: The use of 911 Turbo tie-rod assemblies is permitted.

(l) Hydro-pneumatic Suspension: Removal of this suspension is not only allowed but is encouraged.

(m) A-Arms: 924/944/968 series may use aftermarket A-Arms provided suspension geometry is not altered.

A-2.5.5.3. Brake/Wheel/Tire

(a) Tires: All tires must be Department of Transportation (DOT) approved. Any DOT tire may be used providing they have a visible tread, have DOT wear indicators and have visible tread across the entire tread surface. Tires must have a minimum tread wear of 180 unless it is a Showroom Stock automobile running in the correct Production Category class. Tire aspect ratio and width is free but must fit under the stock fender wells. Tires must be marketed nationally and generally available to all competitors. The cord may not be visible before, during, or after runs. Recapped tires or re-grooved tires are not allowed. Competitors are responsible for policing the "rubbing tire" rule and protests must be made before timed runs.

(b) Track Width: Modifications to track width by the use of wheel spacers and/or wheel offset are permitted provided no modifications to the automobile, other than increasing the stud/bolt length, are performed. Increase may not be more than 1.0” over stock. Only 356 models with drum and very early disc brakes may use individual spacers for each wheel stud.

(c) Brakes: Pads, linings and brake lines of any manufacture may be used. Any type of brake cooling may be used. Rotors may be drilled or slotted. Brake bias valve may be changed but cockpit adjustable valves are not permitted.

(d) Increased Rim Width: Rim width may be increased up to 1.0” over the widest rim available from the factory (front and rear respectively; see Appendix V) for that model range so long as the width does not extend beyond the stock fender width as measured from the top of the tire and fits the stock fender wells.

(e) Wheels: All wheels shall be the same diameter as available from the factory for the model range of the automobile or within an increase or decrease of 1.0” from the factory specifications.

(f) Spare Tire: The supplied spare tire may be removed

A-2.5.5.4. Chassis/Body/Interior

(a) Limited Fender Modifications: Fenders (including wheel openings) may be modified provided the tire

wheel-spacer combination and ride-height setting used could be used without the fender modification (i.e., could be used on an unmodified automobile of the same model and year.) In the event of a protest, the entrant must be able to prove compliance with this rule.

(b) Interior Modifications: Any accessory, gauge or indicator may be fitted if its purpose is to improve driver or passenger comfort or convenience and provided such items have no effect whatsoever on mechanical performance. Alternate seats may be used and floor mats may be removed. Any steering wheel is allowed.

(c) Roll Bars: Roll bars are permitted. Full interior roll cages are not permitted.

(d) Spoilers: Any rear spoiler, unless as delivered as a factory option, is permitted provided the leading edge of the spoiler is attached to the automobile, the spoiler is no wider than the stock body width and the spoiler doesn’t exceed 5”in height from the leading edge.

(e) Air Dams: Any front air dam ,unless as delivered as a factory option, is permitted provided it does not extend to less than 3”above the ground and not forward of the front bumper.

(f) Seam Reinforcement (914 Only): Seam reinforcement kits are permitted "free" on 9l4s, provided each reinforcement is limited to a single seam and that all reinforcements combined do not substantially increase the rigidity and stiffness of the chassis. It is recommended to 914 model owners to have the chassis inspected for rust on a periodic basis.

(g) Bumpers: Bumpers may be removed on any 356 series automobile.

(h) Weight: Automobile must meet minimum weight, as run, without driver. Ballast is not allowed.

(i) Bolt-on windshields: Bolt-on windshields may be removed.

(j) Jack/Tools/Manuals: Removal of jack, tools and owner’s manual(s) is allowed.

A-2.5.5.5. Transmission (a) Limited Slip: Limited slip is permitted in all automobiles

(b) Gear Shift Linkages: Gear shift linkages may be modified or exchanged. This permits the use of a short

shift kit in any automobile or the use of side-shifter transmission in any 914.


 

A-2.5.6. Improved Modifications

The improved category is for street vehicles with modifications beyond those allowed in the Production Category. The modifications are limited but much more liberal than those in the Showroom Stock or Production Categories. The following adjustments, alterations, or modifications are allowed in the Improved class automobiles plus what was allowed in the Showroom Stock and Production classes.

A-2.5.6.1. Engine

(a) Mufflers: Mufflers may be removed provided this is permitted by the event organizer and the local authorities/jurisdiction. (b) Ignition: Any ignition system is allowed.

(c) Gasoline: Any gasoline is permitted.

(d) Engine Substitution: Any Porsche engine is permitted in any Porsche automobile.

(e) Fuel Management: Automobiles may use any fuel management/induction system including chips or other means that alter turbo boost. Turbochargers or superchargers are permitted.

(f) Compression Ratio: Engine compression ratio’s may be increased up to 1.0 points.

(g) Battery Location: The battery may be located anywhere within the automobile.

(h) Intake System: Any intake system may be used.

(i) Wet/Dry Sumps: Any change or addition is permitted.

(j) Camshafts: Any camshaft may be used.

A-2.5.6.2. Suspension

(a) Shocks Absorbers: Multi-adjustable or remotely adjustable shock absorbers are permitted.

(b) Camber Plates: Camber plates are permitted. Machining of factory mounting points is permitted to allow greater suspension adjustment.

(c) Raised Spindle: Raised spindles are permitted on strut type suspensions.

(d) Suspension Mounts: Any suspension mount may be used provided the number of mounting points and

mounting locations remain as factory.

(e) Suspension Arms: Any suspension arm may be used provided use requires no other automobile modifications. For example, this includes the use of any lower control arm, tie-rod assembly and/or bump steer kit.

A-2.5.6.3. Wheel/Brake/Tire

(a) Brakes: Any brake modifications are permitted. Any brake biasing valve is permitted.

(b) Tires: Any DOT tire is permitted. The cord may not be visible before, during or after official timed runs.

(c) Track Width: Modifications to track width are permitted up to 2.0” over stock. Only 356 models with drum and very early disc brakes may use individual spacers for each wheel stud.

(d) Increased Rim Width: Rim width may be increased up to 2” over widest rim available from the factory (front and rear respectively; see Appendix V) for that model range so long as the width does not extend beyond the fender.

(e) Wheels: Wheels may be any diameter.

A-2.5.6.4. Chassis/Body/Interior

(a) Roll Bars/Roll Cages: Roll bars or full interior cages are permitted. See Appendix XII of PCR’s for additional information, specifications and requirements.

(b) Spoilers: Any spoiler is permitted.

(c) Air Dams: Any front air dam is permitted.

(d) Interior: Automobile, at minimum, must have dashboard, windows (glass or plexiglass), visors (if originally equipped), headliner, and door panels. The original number of seats and passenger restraints must be present. Removal of mats and loose carpeting is allowed (i.e., what isn't originally screwed and/or glued down). Headlights, taillights, brake lights and turn signal lights must be operational.

(e) Bodywork: The use of fiberglass or other material body components is permitted for the following components: hoods (front and rear), rear deck lids, bumpers and rocker panels.

(f) Fenders: Fenders may be altered to allow fitting of alternative wheels and tires. All four tires shall not extend beyond the fender opening at the highest point of the tire, unless the Porsche model was originally an open-wheeled design.

(g) Fuel Tanks: Fuel tanks may be changed and/or relocated.

A-2.5.6.5. Transmission

(a) Transmission: Any Porsche based transmission is permitted.

(b) Transaxle gear ratios. Any ratio set may be used outside of the specified gear set. Ring and pinion may be altered.

(c) Limited Slip: Any limited slip may be used.

 

 

A-2.5.7. Modified Modifications

The modified category includes all automobiles modified beyond the allowable limits specified in the Showroom Stock, Production and Improved categories as well as some Limited Production and “tuner” automobiles. These rules provide the minimum that is required for the automobile to compete in this category. Some items are specified that are not allowed in this category. Unless defined as a production vehicle with complete documentation proving so, all racing, rally and special non-production Porsche models shall be included in this category.

A-2.5.7.1. Engine

(a) Engine: A Porsche based engine is required.

(b) Displacement: The displacement may be increased to that of the maximum in the class.

(c) Fuel Management: Modifications to the fuel injection or carburetion system are free. The use of turbochargers or superchargers other than those used in production is permitted by class allowance. Modified boost pressure is permitted.

(d) Ignition: Any ignition system is permitted.

(e) Nitrous Oxide Systems: These systems are not permitted.

A-2.5.7.2. Suspension

(a) Machined Suspension: Any adjustment may be made and machining is allowed (such as machining to attain negative front camber on 356-series cars). Suspension points may be relocated.

(b) Multi-linked Suspension: This suspension type is permitted and is free.

A-2.5.7.3. Wheels/Brake/Tire

(a) Wheel and Tire: Any wheel and tire combination is permitted. Non-DOT tires are permitted. The cord may not be visible before, during or after official timed runs.

A-2.5.7.4. Chassis/Body/Interior

(a) Chassis: Original Porsche based chassis, unibody or tube frame chassis is permitted. (b) Roll Bars/Roll Cages: Roll bars or full interior cages are permitted. In some instances, they may be required. See Appendix XII of PCR’s for additional information, specifications and requirements.

(c) Bodywork: Automobile bodywork must maintain recognizable external features of the Porsche model. Tires may extend beyond the fender opening. Automobile bodywork must include a front and rear trunk or deck lid and doors.

A-2.5.7.5. Transmission

(a) Transmission: Any transmission is required.

 

 

A-2.5.8. Other Modifications

Any equipment, component, part, or modification which is deemed performance-affecting and which is not specified will make the automobile entered subject to reclassification to a higher class or category by the Safety Inspection team or the Protest Committee at their discretion or by protest of a competitor in the same class the automobile is competing.

 

You can find the appropriate class for your vehicle in the table below:

Type Model From To Stock Production Improved Modified
  356 1948 1965 S01 P01    
  4 Cylinder 1948 2019     I01 M01
  4 Cylinder Turbo 1948 2019     M02 I01
  6 Cylinder to 2399cc 1948 2019     M01 I01
  6 Cylinder, 2400cc to 3199cc 1948 2019     I02 M02
  6 Cylinder, 3200 and above 1948 2019     I02 M02
  6 Cylinder Turbo 1948 2019     I02 M02
  912 1965 1969 S01 P01    
  911 1965 1969 S02 P02    
  914/4 1970 1975 S01 P01    
  911 1970 1971 S02 P02    
  914/6 1970 1972 S02 P02    
  911 1972 1973 S02 P02    
  911 1974 1977 S02 P02    
930 911 Turbo 1976 1989 S05 P05    
  912E 1976 1976 S01 P01    
  924 1976 1982 S01 P01    
  928/928S 1978 1986 S03 P03    
  911SC 1978 1983 S03 P03    
931 924 Turbo 1979 1982 S02 P02    
  944 1983 1989 S02 P02    
  911 Carrera 1984 1989 S03 P03    
951 944 Turbo 1986 1989 S03 P03    
  924S 1986 1988 S02 P02    
  944S 1987 1989 S02 P02    
  928S4/CS/GT/GTS 1987 1995 S03 P03    
964 911 Carrera 1989 1994 S04 P04    
  911 Speedster 1989 1989 S03 P03    
  944S2 1989 1991 S04 P04    
965 911 Turbo 1990 1994 S06 P06    
964 911 America Rdstr 1992 1993 S04 P04    
  968 1992 1995 S04 P04    
964 911 RS America 1993 1994 S04 P04    
964 911 Speedster 1994 1994 S04 P04    
993 911 Carrera 1995 1998 S05 P05    
993 911 Turbo 1995 1998 S07 P07    
986 Boxster 1997 2004 S04 P04    
996 911 Carrera 1999 2005 S06 P06    
986 Boxster S 2000 2004 S05 P05    
996 911 Turbo 2001 2005 S08 P08    
996 911 GT2 2002 2005 S08 P08    
  Cayenne 2003 2019 S01 P01    
  Cayenne S 2003 2010 S01 P01    
980 Carrera GT 2004 2005 N/A P08    
996 911 GT3 2004 2005 S08 P08    
987 Boxster 2005 2012 S05 P05    
987 Boxster S 2005 2012 S06 P06    
997 911 Carrera 2005 2012 S06 P06    
997 911 Carrera S 2005 2008 S07 P07    
987 Cayman 2006 2012 S05 P05    
987 Cayman  S 2006 2012 S06 P06    
997 911 GT3 2006 2011 S08 P08    
997 911 GT3RS 2006 2011 S08 P08    
997 911 Turbo 2007 2012 S08 P08    
997 911 GT2/GT2RS 2008 2012 S08 P08    
997 911 Carrera S 2009 2012 S07 P07    
987 Boxster Spyder 2010 2012 S07 P07    
997 911 GTS and Spdstr 2010 2012 S07 P07    
987 Cayman R 2011 2012 S07 P07    
  Cayenne Hybrid 2011 2019 S01 P01    
  Panamera 2011 2019 S01 P01    
991 911 Carrera 2012 2019 S06 P06    
991 911 Carrera S 2012 2019 S07 P07    
981 Boxster 2013 2016 S05 P05    
981 Cayman 2013 2016 S05 P05    
981 Boxster S 2013 2016 S06 P06    
981 Cayman  S 2013 2016 S06 P06    
  Cayenne Diesel 2013 2019 S01 P01    
918 918 2014 2015 N/A P08    
981 Cayman GTS 2014 2016 S07 P07    
981 Boxster GTS 2014 2016 S07 P07    
991 911 Turbo 2014 2019 S08 P08    
991 911 GT3 2014 2019 S08 P08    
992 912 GT3 RS 2014 2019 S08 P08    
  Macan 2014 2019 S01 P01    
991 911 Carrera GTS 2015 2019 S07 P07    
981 Boxster Spyder 2016 2016 S07 P07    
981 Cayman GT4 2016 2016 S08 P08    
991 911 R 2016 2016 S08 P08    
718 Boxster 2017 2019 S06 P06    
718 Cayman 2017 2019 S06 P06    
718 Boxster S 2017 2019 S07 P07    
718 Cayman S 2017 2019 S07 P07    
718 Boxster GTS 2017 2019 S08 P08    
718 Cayman GTS 2017 2019 S08 P08    
991 911 GT2RS 2018 2019 N/A P08    
991 911 Carrera T 2018 2019 S06 P06    
718 Boxster T 2020   S07 P07    
718 Cayman T 2020   S07 P07    
718 Spyder 2020   S08 P08    
718 Cayman GT4 2020   S08 P08    
718 Boxster GTS 4.0 2020   S08 P08    
718 Cayman GTS 4.0 2020   S08 P08    
992 Carrera 2020   S08 P08    
992 Carrera S/4S 2020   S08 P08    
992 911 Turbo 2020   S08 P08