F5 + FM + SRF + GT3 at Buttonwillow Raceway Park

In SRF, GCR section 9.1.8.E.2.B, change as follows:
"Mandatory identification: "SRF3" near the side car numbers,. Approved (2) “Ford Performance” on each sideof the engine cover
plus a Ford Blue Oval on the center of the Nose & (2) “Performance Electronics” on eachside of the tail. "Hoosier" logo (4) on
both sides front lower outer corners of the nose, and each side of the tail."

In GT3 Engines - MAZDA, MZR DOHC 87.38, change Fuel Induction as follows:
"31 32"

In GT3 Engines - MAZDA, Renesis Bridgeport, change Fuel Induction as follows:
"44 2mm"
In GT3 Engines - MAZDA, 13B Bridgeport, change Fuel Induction as follows:
"44 2mm"

In SRF, GCR section 9.1.8.E.2.H.17, add the following:
"Alternator Pulley: P/N G902130 or P/N G902130A. 12oz minimum weight"

In F500, GCR section 9.1.1.D.14, Snowmobile Derived Engines, add the following:
"Rotax 593 in a carbureted, non-HO or HO version;"
In F500, GCR section 9.1.1.D.14.A, add the following:
"38mm intake boots, BPP 420867860 (last 6 digits 867860 are embossed on the boot), BPP 420867862 (last 6 digits 867862 are
embossed on the boot), or Kimpex 07-100-33, shall be used for the 493 and 593 non-HO engines. 38mm intake boots, BPP
420867882 (last 6 digits 867882 are embossed on the boot) shall be used for the 2003 593 HO engine, and BPP 420867879 (last 6
digits 867879 are embossed on the boot) shall be used for the 2004-2007 593 HO engines."
In F500, GCR section 9.1.1.D.14.I.3, add the following:
"Rotax 593 non-HO (0.010" overbore): Rotax P/N 420889171"
In F500, GCR section 9.1.1.D.14.J.3, add the following:
"Rotax 593 non-HO engine only: Rotax OEM 0.010" overbore piston (P/N 420889171)."
In F500, GCR section 9.1.1.D.14.K, add the following:
"Rotax 593 non-HO engine only:"
In F500 Engine Table, add the following:
F500 Version/Model Weight
(lbs) Inlet Restrictor Outlet Restriction Notes
Rotax
593*
Carbureted HO
version (03-07) 875 MA0242SP1020A
or
MA0242SP1063A
Y-pipe exhaust
manifold and single
expansion chamber (ref
9.1.1.D.14.B)
Note 1 and 4. Restrictor size and
type is to be displayed by the
following designation: 593 RSTR

In GCR, Section 9.1.2.F.3. add the following:
"8. Current FP spec line cars may compete in GT3 as long as they maintain their full FP rule set."

In GCR, Section 9.1.2.G.16., change as follows:
"0-80541-1 0-80541-2"
In GCR, Section 9.1.2.G., Appendix Z 5.a. change as follows:
"0-80541-1 0-80541-2"
In GCR, TA2 Appendix B.3.4, change as follows:
"#6010 6014X"

In SRF, GCR section 9.1.8.E.1.X.f, make changes as follows:
"Dry:
Front – Hoosier P/N 46340 P185/60ZR13 SRF
Rear – Hoosier P/N 46350 P205/60ZR13 SRF
Wet:
Front – Hoosier P/N 46100 P185/60R13 H20
Rear – Hoosier P/N 46105 P205/60R13 H20
or
Front – Hoosier P/N 46100 P185/60R13 W2 (effective Oct. 4, 2021)
Rear – Hoosier P/N 46105 P205/60R13 W2 (effective Oct. 4, 2021)"

In F5, GCR section 9.1.1.D.6.B.4, make changes as follows:
"All gear changes must be initiated and made completed by the driver. Only mechanical gear shifting mechanisms are permitted.
This may include cables, rods, or other mechanical linkage systems. All other shifting mechanisms are not permitted. This
prohibition shall include electric solenoid shifters, air-shifters, etc. and other devices not mechanically actuated and controlled
completely by the driver. Devices that allow pre-selected gear changes and closed-loop systems that use feedback from sensors
to vary the timing of the gear selection process are also prohibited.
Devices that interact with the throttle, ignition, or fuel system during a shift operation (for example: ignitions cuts, flat shifters,
blippers) are permitted, but no such devices shall remove the driver's control of the gear change initiation, gear selection or
completion. The burden of proving that a device is in compliance with this rule shall be upon the competitor."

In SRF, GCR section 9.1.8.E.2.K, make changes to gear ratios as follows:
"Gear Ratios:
Ford/Mazda OEM 5-Speed:
1st 3.42 : 1
2nd 1.84 : 1
3rd 1.29 : 1
4th 0.97 : 1
5th 0.77 : 1
Final Drive Ratio: 3.85
OR
SADEV-SRF3 6-Speed Sequential (beginning Oct. 4, 2021):

A specification table follows in the original; it is not shown here.

In SRF, GCR section 9.1.8.E.1.C, make changes as follows:
"If any official Enterprises seal is broken, by an Enterprises Customer Service Rep. (CSR) emergency field repair, accident, or
intent, the procedures outlined under C.20., section S shall be followed. Parts with an Enterprises part number having the prefix
"10" are considered to be unrestricted, providing provided their dimensions are comparable."
In SRF, GCR section 9.1.8.E.1.S, make changes as follows:
"SCCA Enterprises' seals on engine are required for all races must be present on driveline components in designated locations for
all SCCA sanctioned events. Any competitor who runs participates in an event without all proper engine seals in the required
locations shall have his engine removed and shipped to Enterprises for testing and sealing after that event must remove his
unsealed component and it must be inspected by a Customer Service Rep. (CSR) or Enterprises. Notation shall be made in the
vehicle logbook and seals checked prior to the next event. The competitor will be responsible for all cost incurred by this
procedure. regardless of the findings, and If the component is found to be out of specification, the competitor is subject to
penalty by the SOM if engine is found to be not as specified."
"SCCA Enterprises' seals are required on all SPEC RACER FORD engines and transmissions."

In F5, GCR section 9.1.1.D.1, change as follows:
"A class for single seat, open wheel, rigid limited suspension race cars using either a snowmobile-derived engine and drive
components or a 600cc motorcycle engine."

In GT3 Engines - VOLKSWAGEN, classify Fun Cup Beetle EVO3 as follows:
GT3 Engines - VOLKSWAGON

A specification table follows in the original; it is not shown here.

In GT3 Cars - Ford, classify Ford Cortina GT as follows effective 11/1/2021:
GT3 Cars - Ford
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
Ford Cortina GT 64-68 2dr. RWD 98.0 “

In SRF, GCR section 9.1.8.E.1.X.f, change as follows:
"Wet:
Front – Hoosier P/N 46100 P185/60R13 H20
Rear – Hoosier P/N 46105 P205/60R13 H20
Ground clearance is 2.5" with driver as raced when H20 tires are used.
or
Front – Hoosier P/N 46100 P185/60 65R13 W2 (effective Oct. 4, 2021)
Rear – Hoosier P/N 46105 P205/60R13 W2 (effective Oct. 4, 2021)"
In SRF, GCR section 9.1.8.E.2.H.24, change as follows:
"Air Box: P/N G592230 Mandatory unmodified As delivered, except as noted under body work, Air Box floor vent must remain
open and un-obstructed."
In SRF, GCR section 9.1.8.E.2.H, add a new section as follows:
"25. SRF3 Restrictor plate: P/N G301048 As delivered, installed between throttle body and intake manifold. Mandatory Jan. 1,

A specification table follows in the original; it is not shown here.

In GT3 Spec Lines, Engines - Volkswagen, “Fun Cup” Beetle Sealed, change weight as follows:
"2060 1850"

In GT3 Spec Lines, classify TCR cars as follows:
GT3-TCR
Make Model Trans Power Level Weight (lbs) Notes
Audi RS3 LMS
(2016-2020)
SEQ 100% 3175 Must use 200 tread wear tires
Audi RS3 LMS
(2016-2020)
DSG 100% 3100 Must use 200 tread wear tires
Honda Civic Type R
(2016-2020)
SEQ 100% 3200 Must use 200 tread wear tires
Hyundai I30N
(2016-2020)
SEQ 100% 3200 Must use 200 tread wear tires
Volkswagen Golf GTI
(2016-2020)
SEQ 100% 3175 Must use 200 tread wear tires
Volkswagen Golf GTI
(2016-2020)
DSG 100% 3100 Must use 200 tread wear tires

In F5, GCR section 9.1.1.D, add a new section as follows:
"19. All F5 cars competing in Majors Races and the Runoffs must have the AIM part #X47KPFSOLO2R0 data box mount installed
on the vehicle to provide the necessary mounting of the AIM Solo or Solo 2 data box. The mounting surface is to be approximately
oriented either horizontally or vertically either parallel or perpendicular to the longitudinal axis of the car and must be accessible
from the exterior of the car with the driver on board -- it should have a view of the sky and not be located under carbon fiber or
metallic bodywork. Sufficient space should be left between the mounting plate and the surface to which it is attached to permit
the use of zip ties/tie straps to restrain the data box to the mounting plate. The purpose of this requirement is to allow the
random placement of data boxes on cars on pre-grid by SCCA assigned personal and the collection of the box when the car exits
the race track. Contact AIM and their distributors for direct purchase."

In GT3 Spec Lines, classify Fiat Spider 2000, Years 79-81, as follows:
GT3 Cars - FIAT
Model Years Body Style Drive-line Wheel-base (in) Notes
Fiat Spider 2000 79-81 RWD 89.76”

In GT3 Spec Lines, classify Fiat X-19, Years 72-89, as follows:
GT3 Cars -
Model Years Body Style Drive-line Wheel-base (in) Notes

In GT3 Cars - Ginetta, classify Ginetta G40 as follows:
GT3 Cars - GINETTA
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
Ginetta G40 2010-
Present
2 Door Coupe RWD 88.6 Must comply with all GT3 rules except as
noted on spec line. May use FIA roll cage.
Must have complete build specs in
possession at all race events.
In GT3 Engines - Ginetta (Ford/Mazda), as follows:
GT3 Engines – GINETTA (Ford/Mazda)
Engine Family Bore x Stroke (mm) Disp.
(CC)
Head Type Valves
/ Cyl.
Fuel
Induction
Weight (lbs) Notes

A specification table follows in the original; it is not shown here.

In GT3 Engines, classify MAZDA MZR as follows:

A specification table follows in the original; it is not shown here.

In GT3 Cars - Volvo, classify Volvo S60 as follows:
GT3 Cars - VOLVO
Model Years Body Style Drive-line Wheel-base (in) Notes
Volvo S60 2000-2009 4 Door Sports
Coupe
FWD 106.9

In GT3 Engines Spec Lines, add to Notes the following:
Acura F20C 1997cc: "May run unrestricted at 2195 lbs."
Acura K20A 1998cc: "May run unrestricted at 2195 lbs."
Audi 1984cc: "May run unrestricted at 2195 lbs."
BMW 1895cc: "May run unrestricted at 2195 lbs."
Chevrolet 1998cc: "May run unrestricted at 2195 lbs."
Chrysler/Dodge/Plymouth 1997cc: "May run unrestricted at 2195 lbs."
"Ginetta 1999cc: May run unrestricted at 2195 lbs."
Honda F20C 1997cc: "May run unrestricted at 2195 lbs."
Honda K20A 1998cc: "May run unrestricted at 2195 lbs."
Mazda 1999cc: "May run unrestricted at 2195 lbs."
Mitsubishi/Eagle 1997cc: "May run unrestricted at 2195 lbs."
Nissan QR25DE/DD 1998cc: "May run unrestricted at 2195 lbs."
Nissan SR20-DE/VE: "May run unrestricted at 2195 lbs."
Saab 1985cc: "May run unrestricted at 2195 lbs."
Volkswagen1984cc: "May run unrestricted at 2195 lbs."

In GCR, Section 9.1.2.F.7.b.12.E., change the following:
"A single element, single plane airfoil scaled up to a maximum chord length of 10.75 inches."

In F500, GCR section 9.1.1.D.19, change as follows:
"All F500 cars competing in Majors Races and the Runoffs must have the AIM part #X47KPFSOLO2R0 data box mount installed
on the vehicle to provide the necessary mounting of the AIM Solo or Solo 2 data box."

In GT3 Spec Lines, GT3-TCR, change as follows:
Make/Model Audi RS3 LMS (2016-2020) SEQ:
Power Level: "100% 90%"
Weight: "3175 3177"
Notes: "Must use 200 tread wear tires. No tire shaving permitted. Stock TCR wheels only."
Make/Model Audi RS3 LMS (2016-2020) DSG:
Power Level: "100% 90%"
Notes: "Must use 200 tread wear tires. No tire shaving permitted. Stock TCR wheels only."
Make/Model Honda Civic Type R (2016-2020):
Power Level: "100% 90%"
Weight: "3200 3210"
Notes: "Must use 200 tread wear tires. No tire shaving permitted. Stock TCR wheels only."
Make/Model Hyundai I30N (2016-2020):
Power Level: "100% 90%"
Weight: "3200 3254"
Notes: "Must use 200 tread wear tires. No tire shaving permitted. Stock TCR wheels only."
Make/Model Volkswagen Golf GTI (2016-2020) SEQ:
Power Level: "100% 90%"
Weight: "3175 3177"
Notes: "Must use 200 tread wear tires. No tire shaving permitted. Stock TCR wheels only."
Make/Model Volkswagen Golf GTI (2016-2020) DSG:
Power Level: "100% 97.5%"
Notes: "Must use 200 tread wear tires. No tire shaving permitted. Stock TCR wheels only."

In Grand Touring Category Specifications, GCR Section 9.1.2.F.10.b, change as follows:
"The maximum wheel size for GT3 cars is 15 x 7”. Alternatively: GT3 cars may run up to a maximum 17" x 9" wheel with a weight
penalty equal to three (3) percent of the car's weight as listed on the specification line. The maximum vehicle weight shall be
rounded to the nearest pound.
Alternatively, a Additionally: Any wheel up to 18” with a maximum tire cross section of 12.0” and a maximum tire diameter of
26.0” may be used with a weight penalty equal to eight five (5) percent of the car’s weight as listed on the specification line. The
minimum vehicle weight shall be rounded to the nearest pound. A maximum brake rotor diameter of 13.0” may be used with
alternate wheels. Cars using 15” American Racer 23.5- 10.0-15, bias ply, non-belted tire may do so without the weight penalty."

In GT3 Cars - FIAT Spec Lines, classify 124 Spider Pinnafarina Spider as follows:
GT3 Cars - FIAT
Model Years Body Style Drive-line Wheel-base (in) Notes

In F500, GCR section 9.1.1.D.14.A, change as follows:
"Carburetor mounting shall must be of individual runners, with no balance pipes, and no plenums unless fitted as standard as on
the Rotax 493 and 593 engines. The use of the intake plenum/resonator on the 493 and the 593 engines is optional. If the intake
resonator is removed the resulting holes MUST be completely plugged and the plugs must be held in place by appropriate
clamps. Plugs may be of any material and must serve no other purpose than to plug the holes originally intended for the
resonator. 38mm intake boots, BPP 420867860 (last 6 digits 867860 are embossed on the boot), BPP 420867862 (last 6 digits
867862 are embossed on the boot), or Kimpex 07-100-33, or Moto Tassinari V-Force 3 Reed Valve System V3124-873B-
2 shall must be used for the 493 and 593 non-HO engines. 38mm intake boots, BPP 420867882 (last 6 digits 867882 are
embossed on the boot) or Moto Tassinari V-Force 3 Reed Valve System V3124-873B-2 shall must be used for the 2003 593 HO
engine, and 38mm intake boots, BPP 420867879 (last 6 digits 867879 are embossed on the boot) or Moto Tassinari V-Force 3
Reed Valve System V3124-873B-2 shall must be used for the 2004-2007 593 HO engines. Supercharging, turbocharging, and
direct fuel injection are prohibited."
In F500, GCR section 9.1.1.D.14, add a new section as follows:
"M. The stock oil injection pump, oil lines, and control cables may be removed from all Rotax engines. The oil injection ports may
be removed and plugged as necessary."

In SRF, GCR section 9.1.8.D.1.X.f, change as follows:
"Tires: must be run as delivered."

In SRF, GCR section 9.1.8.D.1.X.g, change as follows:
"Brakes: Hawk Blue 9012 pads P/N 801993 must be used. Wilwood vented rotor P/N 800065 shall be used as delivered with no
machining of any kind. Minimum thickness 13.25 12.20mm (0.522 0.481"). The 1985 Renault Alliance solid front rotor (Reference:
Bendix PRT1318 or Centrix 121.11004) may be used on front, rear, or both axles, but each axle must be paired to the same type
rotor. Rubber caliper bushings may be replaced with bronze bushings P/N 1196185 or P/N 1196185."
In SRF, GCR section 9.1.8.D.2.H, change as follows:
"No performance M modifications of any kind.
SCCA Enterprises’ seals shall be intact.
(2) on cam cover, (2) on the oil pan, (1) on the each cam shaft. Automatic Drivetrain Violation if removed."
In SRF, GCR section 9.1.8.D.2.H.23, change as follows:
"Air Filter: P/N WM301020 or K&N RC-9160"

In F500, GCR section 9.1.1.D.15.G, add the following:
"The exhaust system and exhaust manifold are unrestricted, within SCCA safety regulations, except that
stepped diameter exhaust headers are not allowed. This prohibition does not include the exhaust flange area immediately
adjacent to the cylinder head."
In F500 Engine Table, Honda CBR600RR, Suzuki GSXR600, and Yamaha R6 spec lines, add the following:
"Stepped diameter exhaust headers are not allowed"

In GT3 Spec Lines, Cars - Fiat, change model as follows:
"124 Spider Pinnafarina Pininfarina Spider"

In GT3 Engines, Nissan, classify SR20VET Limited Prep-Turbocharged OEM Engine as follows:
GT3 Engines - NISSAN
Engine Family Engine

A specification table follows in the original; it is not shown here.

In F500, GCR section 9.1.1.D.14, add a new section as follows:
"N. Alternate ECU for Rotax engines: The use of the Ingi Tech Sparker ignition part number DCP-CDI-P2 is permitted."

In GT, GCR Section 9.1.2.F.7.a.6:
"Glass and/or plastic headlights, front parking lights, front signal lights, lenses, and bulbs shall be removed. Headlight openings
shall be covered with a wire mesh screen or panel having the same contour as the original lens, mounted so that the headlight
bezel/rim remains in place, maintaining the standard appearance of the Production automobile. Side marker light assemblies
shall be removed and the resulting openings covered with a plate whose dimensions do not exceed those of the original parts;
side marker lights that are an integral part of the taillight assembly cannot be removed. Other lighting parts and operating
mechanisms may be removed. In the case of pop-up headlights, the entire assembly may be removed and the opening covered
with a screen or plate (as above, without the headlight bezel/rim requirement) which provides a stock appearance. It is not
permitted to relocate the standard headlight, parking light, signal light, etc., openings. Traditional GT cars only. Not allowed with
any "Spec Car, GT2-ST, or any other added non Traditional GT car. Taillights shall be in the original location and shall may be the
original style/type of taillight for the make, model, and year of car. A rear body panel having the same contour as the original
lens area and in the original location, may be fitted with a tail-light graphic of the original style/type frame/lens adhered to it. If
side marker lights are an integral part of the tail-light assembly they must be represented by the panel graphic. These
panel/graphics shall have a functioning red LED lamp assembly fitted through them on both sides of the car to serve as brake
lights. A 15-watt or equivalent rain light may be included with-in this LED assembly or may be a separately mounted single or
dual LED assembly."

In F500, GCR section 9.1.1.D.14.A, change as follows:
“Carburetor mounting must be of individual runners, with no balance pipes and no plenums unless fitted as standard as on the
Rotax 493 and 593 engines. The use of the intake plenum/resonator on the 493 and 593 engines is optional. If the intake
resonator is removed the resulting holes MUST be completely plugged and the plugs must be held in place by appropriate
clamps. Plugs may be of any material and must serve no other purpose than to plug the holes originally intended for the
resonator. 38mm i Intake boots, BPP 420867860 (last 6 digits 867860 are embossed on the boot), BPP 420867862 1 (last 6 digits
867862 1 are embossed on the boot), or Kimpex 07-100-33, or Moto Tassinari V-Force 3 Reed Valve System V3124-873B-2 must
be used for the 493 and 593 non-HO engines. Moto Tassinari V-Force V3120-794A-2 Reed Valve System may be used with any
allowed intake boot on the 493 and 593 non-HO engines. 38mm i Intake boots, BPP 420867882 (last 6 digits 867882 are
embossed on the boot) or Moto Tassinari V-Force 3 Reed Valve System V3124-873B-2 must be used for the 2003 593 HO engine,
and 38mm i ntake boots, BPP 420867879 (last 6 digits 867879 are embossed on the boot) or Moto Tassinari V-Force 3 Reed Valve
System V3124-873B-2 must be used for the 2004-2007 593 HO engines. Supercharging, turbocharging, and direct fuel injection
are prohibited.”

In GT Category Specifications, GCR Section 9.1.2.E.13.l.3., change Engine Displacement (cc) as follows:
"1401-1800 50"

In GT3 Spec Lines, HONDA GT3 Cars, add as follows:
HONDA
GT3 Cars -
Model Years Body Style Drive-line Wheel-base (in) Notes
Civic 84-87 3dr FWD 86.6 Hood bulge allowed, no openings.

In GT3 Engines - Mazda Spec Lines, Mazda BP4W Turbocharged OEM engine, add the following:
GT3 Engines - Mazda

A specification table follows in the original; it is not shown here.

In GCR Appendix L-TA2 rules, Addendum A, change A.2. as follows:
"The throttle body must be either a GM 90mm, electronic, part #1257 → 0790, or Edelbrock 90mm, mechanical, part 33869 or
#3870."
In GTA, GCR Section 9.1.2.G.3., change as follows:
"The throttle body must be either a GM 90mm, electronic, part #1257 → 0790, or Edelbrock 90mm, mechanical, part 33869 or
#3870."

In GT3 Engines Spec Lines, SR20VET Limited Prep-Turbocharged OEM Engine, change as follows:
Fuel Induction: "TURBO w/ 33mm TIR"
Notes: "Garrett GT2560LS GT2860RS Turbo only. OEM “stock” ECU only. ECU is open."

In GT3 Spec Lines, Engines - NISSAN, VG30, remove Spec Line in its entirety.

In GT2, 3, LITE Category Specifications, GCR Section 9.1.2.F.13.m., add the following:
" For GT3 only:
1. As an option, induction system "Chokes" may be used where a SIR is required.
Said chokes shall be fitted to each barrel of carburetor/throttle body and all airflow into engine must pass through them. Choke
size will be the same as listed SIR unless noted.
This option is for normally aspirated cars with SIRs only and does not apply to turbo cars with TIRs."

In GT2, 3, LITE Category Specifications, GCR Section 9.1.2.F.13.m., add the following:
“2. All 2.0 liter 4-valve non-turbo engines currently listed in GT3 shall be permitted to run without any restriction (SIR or chokes)
at 2060lbs.”

In SRF, GCR section 9.1.8.D.X.g, change as follows:
"Brakes: Hawk Blue 9012 pads P/N 801993 must be used. Wilwood vented rotor P/N 800065 shall be used as delivered with no
machining of any kind. Minimum thickness 12.20mm (0.481"). The 1985 Renault Alliance solid front rotor (Reference: Bendix
PRT1318 or Centrix 121.11004) may be used on front, rear, or both axles, but each axle must be paired to the same type
rotor. The Renault Alliance solid front rotors may not be used. Rubber caliper bushings may be replaced with bronze bushings P/N
1196185 or P/N 1196185. Original caliper pistons may be replaced with vented caliper piston P/N 1196184; no other
modification allowed. Wilwood caliper with bracket universal fit P/N 800038 may be used as delivered with no modification of
any kind. Wilwood knock back spring (2.63 lbs.) P/N 800045 may be used as delivered with no modification of any kind;
maximum of one spring per caliper."
P2 Engine Table
Spec
Line Engine Series

A specification table follows in the original; it is not shown here.

In GT Spec Lines, GT1 Cars - Fields Cardinal, classify Fields Cardinal V8 as follows:
GT1 Cars – Fields Cardinal
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
Fields Cardinal V8 2023 2 Dr. RWD 92.0 Roll Cage MUST be modified to comply with
GCR Section 9.4.
In GT Spec Lines, GT1Engines - classify Ford V8 as follows:
GT1 Engines - Ford
Engine
Family
Engine Type Bore x

A specification table follows in the original; it is not shown here.

In SRF, GCR section 9.1.8.D.1.X.f, change as follows:
"Front – Hoosier P/N 46100 1 P185/65R13 W2"

In SRF, GCR section 9.1.8.D.1.X.f, change as follows:
"Wet:
Front – Hoosier P/N 46100 P185/60R13 H20 or W2
Rear – Hoosier P/N 46105 P205/60R13 H20 or W2
Ground clearance is 2.5" with driver as raced when P185/60R13 (H20 or W2) tires are used."

In GCR section 9.1.2.F.7.c.10.b, add the following:
"Any racing tire including DOT is allowed in GT3. Cars using 15” American Racer 23.5-10.0-15, bias ply, non-belted tire may do so
without the weight penalty."

In GT3 Engines - HONDA, classify B20 as follows:
GT3 Engines - HONDA

A specification table follows in the original; it is not shown here.

In SRF, GCR section 9.1.8.D.1.V.j, change as follows:
"Radiator - Enterprises new style P/N 480465 (requires baffle P/N 480464) or P/N 480466 can be used. P/N 480466, may can be
replaced with Automotive P/N 1R698, CU698 or equivalent OEM manufacturer justified by one cross-reference chart equivalent,
as long as the size, shape, and material are the same as the original P/N. The capacity, core thickness, etc., cannot be changed
even if allowed under the above. The competitor is responsible for providing this documentation of the cross-reference P/N."

In GT3 Spec Lines, GT3-TCR, change Notes as follows:
Audi RS3 LMS (16-20) @ 3170 lbs: "Must use 200 tread wear any DOT tires. No tire shaving permitted. Stock TCR wheels only."
Audi RS3 LMS (16-20) @ 3100 lbs: "Must use 200 tread wear any DOT tires."
Honda Civic Type R (16-20): "Must use 200 tread wear any DOT tires."
Hyundai 130 N (16-20): "Must use 200 tread wear any DOT tires."
Volkswagen Golf GTi (16-20) @ 3177 lbs: "Must use 200 tread wear any DOT tires."
Volkswagen Golf GTi (16-20) @ 3100 lbs: "Must use 200 tread wear any DOT tires."

from the current (or before) Table of Contents (TOC), to what is shown in the after TOC.
GTL spec lines will now be contiguous with GT2 and 3 spec lines.
GTA category and spec lines will be moved and renumbered behind GTL. GTA Section will not change but page numbers will, (as
shown in Red italics).
9.1.2.F. GT-2, 3, LITE Category Specifications 314
GT2 Cars 327
GT2/ST 341
GT3 Cars 348
GTL Cars 364
GTA Cars 377
P2 Engine Table B.1
2010 and older
Stock Kawasaki
38.5mm
minimum width 52 inches. AMAC-AM5:
minimum width 54 inches.
P2 Engine Table B.1
2008 and older
Stock Engine Suzuki,
Yamaha,
Honda, BMW
38.5mm
P2 Engine Table B.2 Not required
P2 Engine Table B.3 38.5mm
Modified Engine
950 lbs.
1005cc max
P2 Engine Table B.1 37mm
P2 Engine Table B.2 Not required
P2 Engine Table B.3 39mm
Stock Engine
1050 lbs.

In GT3 TOYOTA Engines, classify Toyota 3S as follows:
GT3 TOYOTA Engines -

A specification table follows in the original; it is not shown here.

In GT3 Spec Lines, GT3 Cars, change as follows:
"Acura F20C 1997cc 32mm SIR May run unrestricted at 2195lbs.
K20A 1988cc 32mm SIR May run unrestricted at 2195lbs.
Audi 1984cc 32mm SIR May run unrestricted at 2195lbs.
BMW 1895cc 32mm SIR May run unrestricted at 2195lbs.
Chevrolet 1998cc 32mm SIR May run unrestricted at 2195lbs.
Chrysler/Dodge/Plymouth 1997cc 32mm SIR May run unrestricted at 2195lbs.
Ginetta MZR 1999cc 32mm SIR May run unrestricted at 2195lbs.
Honda F20C 1997cc 32mm SIR May run unrestricted at 2195lbs.
K20A 1988cc 32mm SIR May run unrestricted at 2195lbs.
Mazda MZR 1999cc 32mm SIR May run unrestricted at 2195lbs.
Mitsubishi/Eagle 1997cc 32mm SIR May run unrestricted at 2195lbs.
Nissan QR25DE/DD 1988cc 32mm SIR May run unrestricted at 2195lbs.
SAAB 1985cc 32mm SIR May run unrestricted at 2195lbs.
VOLKSWAGON 1984cc 32mm SIR May run unrestricted at 2195lbs.

In SRF, GCR section 9.1.8.D.1.W.l, change as follows:
"A Super Bright LEDs Inc. rain / brake light comprised of a single standard trailer oval lamp, 2-1/4 inches x 6-1/2 inches, with
incandescent or LED illumination, P/N PT-STRB-R24, is required in the original roll hoop mounting location. This rule supersedes
GCR section 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. No changes may be made to the original 3-pin connector on the
wiring harness. The secondary filament of the brake light assembly shall must be connected to a switch enabling its use as a rain
light."

In SRF, GCR section 9.1.8.D.1.W.l, change as follows:
"A Super Bright LEDs Inc. P/N PT-STRB-R24 (SCCA Enterprises P/N 180427A) rain / brake light, P/N PT-STRB-R24, is required in the
original roll hoop mounting location. This rule supersedes GCR section 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. No
changes may be made to the original 3-pin connector on the wiring harness. An SCCA Enterprises P/N 1190503 Strobing Brake
Light Pigtail is required. The secondary filament of the brake light assembly must be connected to a switch enabling its use as
a strobing rain light. A Strobing Brake Light Kit P/N 1168003 is available, which includes the brake light and pigtail."

In GT3 Spec Lines, reduce all disenfranchised GT2 cars from 150 lbs to 75 lbs.GT3 MAZDA: Body: RX7 NA 2 DR. RWD 95.3 /
95.5 / 95.7 SP – Please review and provide appropriate layout for GCR.
In GT3 Spec Lines, Engines - MAZDA, add to Notes as follows:
12A Peripheral Port at 2300 lbs.: "Disenfranchised GT2* add 75 lbs."
13B Bridgeport: "Disfranchised GT2 add 75 lbs."
13B Peripheral Port: "Disfranchised GT2 add 75 lbs."

In GT3 Engines - Mazda Spec Lines, Mazda BP4W Turbocharged OEM engine, change Weight as follows:
"2060 1960"

In GT3 Engines - MAZDA Spec Lines, 13B Peripheral Port, change Weight as follows:
"2200 2100"

In GT3 Cars - TOYOTA Spec Lines, classify DR86 as follows:
GT3 Cars - TOYOTA
Model Years Body Style Driveline Wheelbase (in) Notes
DR86 2021-2024 2 DR RWD 101.3

In GT3 Engines - Toyota, 3S, change as follows:
Bore: "84.2 86.0"
Stroke: "90.1 86.0"

In SRF, GCR section 9.1.8.D.1.H, add the following:
"NO MODIFICATIONS ALLOWED. Front brake ducts are required, attached to the openings in the lower radiator baffles, any
flexible 4" duct material allowed, installed length minimum 12" maximum 36" in length. Must be securely fastened, Bracket Part
# P/N 800368 can be used. Shall Must serve no other purpose. An extension may be welded to the side of the throttle pedal to
improve heel-and-toe braking. Master cylinder casting / location must be used as delivered on P/N 180110 Pedal Mounting
support. Aeroquip style -3 braided stainless flex lines only, must attach to all brake components without modification. Brake pad
"anti-rattle" clips must be removed."
In SRF, GCR section 9.1.8.D.1.V, add the following:
"ii. Rear SADEV shift cable aluminum two-piece style clamp may be used. The P/N WM302007A clamp must serve no other
purpose."
In SRF, GCR section 9.1.8.D.1.X.k, add the following:
"Negative camber shall must not exceed 5.0 degrees absolute maximum front and rear."
In SRF, GCR section 9.1.8.D.1.AA.b, add the following:
"2. Height of the radiator opening vertical surface 3 1/2“ +/- 1/2"."
P2 Engine Table B.1
2008 and older Stock
Suzuki, Yamaha,
Honda, BMW
38.5mm
P2 Engine Table B.2 Not required
P2 Engine Table B.3 38.5mm
Modified
Engine
950 lbs.
1005cc max
P2 Engine Table B.1
2008 and older 37mm
P2 Engine Table B.2 Not required
P2 Engine Table B.3 39mm
Stock Engine
1050 lbs.

In GT3 Engines - Toyota, classify the FA24D as follows: see attachment
GT3 Engines - TOYOTA

A specification table follows in the original; it is not shown here.

In GCR Section 9.1.2.G (GTA Category Specifications), change as follows:
“9.1.2.G.III.I
The single-plane rear spoiler must be mounted at an angel angle from 50 to 75 degrees (perpendicular to the ground
being 90 degrees) and may not extend beyond the rear bumper when viewed from directly above the rear
bumper. Spoilers must be a minimum of .063 aluminum or Lexan and may vary in overall height to match the contours
of the bodywork. The rear spoiler dimensions shall not exceed 59.0 inches wide by 5.0 inches in height, (measured on
the material surface) , or 295.0 square inches total surface area. Braces to prevent spoiler deflection are allowed, but
may serve no other purpose.”

In GCR, Section 9.1.2.F.7.5.E. change as follows:
“Direct Injection is not permitted only if it came OE and must be installed using only OE high pressure pump(s), hard and
soft hoses and injectors.”

In GT2/3 modify Spec Line notes as follows:
GT2:
Nissan: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”
GT3:
Mazda: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”
Mitsubishi 4G93: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E. ”
Nissan QR25DE/DD 1988cc: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”
Nissan QE25DE/DD 2489cc: “Direct Injection not permitted, may be used per 9.1.2.F.7.5.E.”

In GT3 Engines - Nissan QR25DE/DD, change as follows:
11111’QR25 0DE/DD”