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AppendixAppendix-

2. base vehicle2.1) The vehicle must be a mass-produced vehicle manufactured and sold by an automobile manufacturer.
2.2) FR, MR, RR, and FF drive systems are allowed.

F2.3) All participating vehicles must have a temporary cancellation certificate and must present theoriginal certificate at the time of the first vehicle inspection each year.
2.4) Vehicles manufactured by automobile manufacturers for the purpose of race entry (sold or producedon the premise that they are not registered) are not permitted.
In addition, it is the participant's obligation to prove that the vehicle in question is a regular aftermarket vehicle in order to qualify as a base vehicle for the competition.

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Appendix-1.6) If the technical committee members determine that any modification or installation is unsafe fromthe standpoint of ensuring safety and instruct the participant to make improvements, the participantmust follow the instructions.

4. engines
4.1) Engine and displacement
Engines that are composed of parts for mass-produced vehicles are allowed to be used. There are no
restrictions on engine displacement, and engines will not be classified accordingly.
4.2) Fuel
Fuel used must be unleaded gasoline or diesel fuel produced by an oil company and sold at regular
gas station pumps in Japan.

Appendix-C11.5) It is the duty of each Participant to ensure that his/her vehicle not only conforms to these rules at all
times during the competition, but also that it is maintained and inspected to ensure that it is in safe
condition for competition at all times.

3.7) Competitors' vehicles must not have any equipment that may make them legally incompatible.

D1

Appendix-1.4) All vehicles participating in the competition must be certified by the Participant as conforming tothese rules.

3.6) Competition vehicles must be certified by the entrant to conform to these vehicle rules.

4.3) Engine Conversion
When replacing an engine with a different engine type, it is permitted to use an engine within themodel lineup of a mass-produced vehicle or to replace the engine in another mass-produced vehicle
on the market. The converted engine must fit completely within the engine compartment of thestandard car. In addition, the front axle weight of the competition car must not exceed 120% of thebasic car.
4.3.1) When converting an engine, cutting other basic monocoque including the main frame is notallowed in the body modification (including body cutting) as stipulated in 12.2) of this rule.
4.3.2) When a car with a modified engine is entered, the entry will not be accepted unless clear
photographs are submitted and approved showing a full view of the engine compartment, how
the engine is mounted, and its relationship to the car body, including members and bulkheads.
4.3.3) When building a new car with a new engine, a detailed description of the modification points
with engine modification plans and a list of modification items (engine mount manufacturingmethod, manufacturer, etc.) must be submitted to D1JO. After receiving approval, themodification work must begin, and detailed photographs of the manufacturing process(manufacturing status) must be submitted to D1JO before the engine is installed, andphotographs of the engine room and engine mounting method (engine mounts alone andwhen installed), and clear photographs taken immediately after completion so that themembers and other parts of the vehicle's underside can be confirmed. The vehicle will not beallowed to undergo official vehicle inspections unless these photos are submitted to the D1JO
immediately after completion.

Appendix-

B

Appendix-1.3) Permitted or required changes and additions
Regardless of whether or not a car is officially recognized or registered with the FIA and ASN, FIA
Supplementary Regulations J, Articles 252 and 253 shall apply, but the articles presented in theseRegulations shall take precedence over such articles, and all modifications not expressly permitted
by these Regulations are prohibited. Any modifications that are permitted must not be accompanied
by modifications that are not permitted.

3.5) Any appearance that differs significantly from the production car is not allowed.

D2A1.2) In the event that any of the items listed in these regulations conflict with FIA Supplementary
Provision J, Articles 252 and 253, the items listed in these regulations must be followed.

3.4) Open-top cars must be equipped with a hard top.

Appendix-

Appendix-

1. general provisions
1.1) Items not explicitly mentioned in these Regulations must meet the requirements of Article 252 andArticle 253 of J of the FIA Supplementary Regulations. Any modifications not specified as permitted
modifications in these rules and regulations are prohibited.

3.3) When competing, the vehicle must be equipped with at least two seats (driver and front passenger).
Competition vehicles must not be equipped with seats other than these two seats.

E

D1 Regulations

These rules apply to the fabrication and modification of competition vehicles participating in D1
competitions. For the purpose of ensuring the safety of competitions and maintaining the development
and characteristics of D1 competitions, the necessary items as vehicle rules for the D1 Middle Category
are defined as follows.
The D1 ASSOCIATION reserves the right to establish rules for these regulations, and any changes for the
purpose of ensuring safety may be applied immediately without notice.

3.2) The weight of the competition vehicle shall be between 1000 kg and 1550 kg. No vehicle shall exceed
5000 mm in length, 2000 mm in width, and 1500 mm in height.
Competition vehicle weight is defined as the weight of the vehicle during the entire duration of thecompetition, excluding the driver.
It cannot exceed the maximum catalog vehicle weight during the standard vehicle type.

Appendix-

D2 Vehicle Regulations

3. basic requirements for competition vehicles
3.1) The vehicle must be a stock body manufactured by the automobile manufacturer and must be able toconfirm the VIN number stamping.

F

Revised January 1, 2024

Appendix-

D1 Regulations Appendix-C2

5. additional engine equipment
5.1) Any additional supercharger may be added.
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D1

AppendixAppendix-

D2
Appendix-6.3) If a separate fuel collector tank is installed, it must have a maximum capacity of 5 liters, and if
installed inside the cabin, it must be securely sealed with a metal bulkhead.

E

7. exhaust system
7.1) Exhaust volume must not exceed 113db on the A scale as measured at the trackside during
competition. However, the exhaust volume limit may change depending on the venue used, in whichcase it will be stated in the Special Regulations for the event in question.

Appendix-F7.2) Exhaust catalysts are mandatory.
7.3) Exhaust gas must not be released to the atmosphere from the wastegate (exhaust gas around theengine compartment), but must merge into the exhaust pipe, or face backwards behind the fuel tank,or sideways behind the wheelbase center.
7.4) The exhaust outlet must be located at the rear end of the vehicle. No combustible materials may beplaced near the exhaust outlet.

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Appendix-6.2) Effective insulation must be provided around the fuel tank and muffler exhaust pipe.

Transmission and differential oil catch tanks
8.2.1) Oil catch tanks must be fitted.
8.2.2) Oil catch tanks must have a reliable function to prevent oil from spilling onto the track andinto the car body. The catch tank must not be temporarily attached with wire, tape, etc., butmust be secured with a hose nipple, hose band, etc., to prevent disconnection.
8.2.3) The transmission oil catch tank must be a metal or plastic tank with a capacity of 200 liters
or more and must be mounted outside the vehicle.
8.2.4) The differential oil catch tank must be a metal or plastic tank with a capacity of 100 liters or
more, and must be installed outside the vehicle.
8.2.5) If transmission and differential oil catch tanks are shared, their total capacity must be 300㏄
or more.
8.2.6) Oil catch tanks must have an outlet and must always lead to the outside of the cabin andoutside of the vehicle body.
8.2.7) Breather piping and hoses must be secured alone, without being co-tightened with otherpiping and wiring.

Appendix-

C1

Appendix-

6. fuel tank6.1) When relocating or changing fuel tanks, only FIA or JAF approved or SFI Spec. 28.2 or higher safety
fuel tanks are allowed. In addition, the safety fuel tank must have an approved label or certificate
issued by the manufacturer, and in no case may it be used for more than 7 years from the date of
manufacture.

8.2)

D2

B

Appendix-5.7) Water spray on the heat exchanger is permitted, but the structure must be such that there is no
significant leakage of water outside the vehicle. Up to 5 liters of liquid for auxiliary cooling purposes(water spray) may be carried on board, and must be securely fastened.

Appendix-A

Appendix-5.6) Engine oil catch tank
5.6.1) An engine oil catch tank must be installed, and only an engine oil catch tank with a capacity of
2 liters or more and made of metal is allowed.
5.6.2) Blow-by gases must be closed (open to the atmosphere is not allowed). The outlet of the oilcatch tank must be connected to a suction pipe or similar (inside the engine) to return blow-bygas.
5.6.3) The engine oil catch tank shall be mounted in the engine compartment.
5.6.4) Temporary oil catch tank mounting methods such as wire or tape shall be prohibited. In
addition, the oil catch tank must have a reliable function to prevent oil from spilling onto thetrack and into the car body.
5.6.5) Hoses used must be oil- and heat-resistant, and must have disconnection and heat protection
measures. They must be secured independently from other piping.
5.6.6) Engine oil level gauges must be equipped with a retaining device.

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D1 Regulations

5.5) An oil cooler may be installed, but the mounting position method must be considered to prevent oilleakage due to collisions, etc.

Appendix-5.4) The basic arrangement of the radiator from the engine compartment to outside the engine
compartment, etc. must not be changed.

8. transmission and differential
8.1.1) The transmission may be changed freely, but must have a rearward traveling function.
Modifications to the floor and other parts of the vehicle due to transmission changes are permitted
to the extent that the modifications do not exceed the punching out and reinforcement of theinterfering parts. If modifications or reinforcements are required to the monocoque or members,
including the bulkhead, transmission tunnel, or floor, the modification plan and list of modification
items must be submitted to D1JO in advance with a "Detailed Description of Modification Areas"
and must be approved before the modification work begins. In addition, detailed photographs of themodification work in progress (production status) and photographs of the modification work after
completion must be submitted to D1JO immediately after completion.
8.1.2) Vehicles with differential case geometry changes that involve modification or alteration of thepropeller shaft must be equipped with a valid propeller shaft loop in accordance with D1 Vehicle
Regulations 5 Power Train 5.4. The shaft shall have a loop structure that encircles the shaft 360°
from the universal joints at both ends of the shaft, and the loop shall be the minimum diameterrequired. They also shall be securely attached to the main body floor by a steel flat band 6.35 mm
thick × 51 mm wide or 1.6 mm thick × 22 mm diameter or larger steel pipe, welded or attached tothe main body floor by M8 or larger bolts and nuts in at least four places. The propeller shaft loop
shall be relocated or added to the area where there is a high possibility of breakage.
8.1.3) Vehicles that have undergone engine modification involving modification or alteration of thepropeller shaft, transmission case geometry modification, or cutting and welding of the floor
tunnel shall be obliged to install an effective propeller shaft loop in accordance with D1 Vehicle
Regulations 5 Power Train 5.4.

9. brake system
9.1) Modifications to the brake system are permitted, but it must be a two-system safety circuit andconstructed to brake all four wheels simultaneously.

F5.3) Nitrous oxide gas injection systems (NOS, etc.) are not permitted.

7.5) Exhaust outlets must face backwards or downwards and must not protrude beyond the outside of thevehicle within the overall length of the vehicle.

Appendix-5.2) A valid air cleaner must be installed, even if a funnel is installed on an independent throttle such as a
4-throttle throttle.

9.2) Manual brakes must operate only on the rear wheels, must be completely separate from the main
brake actuation system, and must operate simultaneously on both sides.
9.3) The use of carbon fiber rotors is not permitted, unless they are adopted by the officially adopted.
9.4) Oil reservoir caps for brakes and clutches must be secured to prevent detachment and leakage.

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Portion where musut not to be seen

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11.3) When the tire is viewed
from above the car
body in a straight line,
the portion of the tire
above the horizontal
line at the top of thewheel must not be
visible beyond thefender.

12.2) Body modifications (including body excision)
12.2.1) Partial excision of other basic monocoque including the main frame is not allowed.
However, minor modifications involving the minimum necessary shape change to prevent
interference with modified parts are permitted to the extent that there is no reduction instrength.
12.2.2) The overall width of a participating vehicle shall be limited to 150 mm above the original(stock) vehicle width for modifications such as the installation of over fenders.
12.2.3) Over fenders shall not be of a temporary nature, shall be firmly fixed, and shall not havegaps between them and the vehicle body.
12.2.4) The tops of tires shall be covered by fenders, not by the addition of simple moldings, panels,
etc.
12.2.5) The flange portion of the fender arch may be bent inward to avoid contact with the tire.
However, in the case of synthetic resin, minimal cutting of that portion is permitted.
12.2.6) If the rear wheel arch section is cut away to accommodate an overfender, the wheel housing
and rear quarter panel must be welded together.
12.2.7) Roof panels may be converted to composite material, but the channel structure panels
at the edge of the roof panel must be retained. If the roof panel is changed to composite
material, it must be reinforced in accordance with the FIA International Motor Sport
Regulations, Appendix J, Article 253, Safety Equipment, Section 8, Safety Gauge 8.3.2.1.3)
Roof Reinforcement.
12.2.8) Vehicles equipped with sunroofs must not have an opening/closing mechanism and must
be securely fastened to the roof panel. If the sunroof is made of glass, it must be made of asafe material other than glass and securely fastened.

Appendix-

Appendix-11.2) The maximum nominal
width of tires that may
be used is 265.

12. car body12.1) Doors
12.1.1) The driver and passenger doors must be unmodified production car doors.
12.1.2) Door linings are permitted to be replaced with other non-combustible materials.
12.1.3) The rear doors of 4-door vehicles may only have their linings inside removed.
12.1.4) Door sealing must function to block the passage of air from the tire house.

E

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Appendix-

11. tires and wheels
11.1) Tires must be commercially available tires for use on public roads. Only the tire brands listed in
the latest edition of the "D1GP Series Tire List", which will be published separately from the 2024
Series, may be used.

11.6) Wheel spacers
11.6.1) Stacking wheel spacers or using inadequately accurate wheel spacers is not permitted.
11.6.2) Wheel bolts must be specially designed and manufactured by a reputable manufacturer.
11.6.3) When spacers with a thickness exceeding 10 mm are used, they shall be bolt-fixed and the
maximum thickness shall be 40 mm.
The fixing bolts for spacers shall be equivalent to those in 2) and torque check shall not be
neglected.
11.6.4) Hub bolts must be properly managed to prevent damage under any circumstances. If a
wheel comes off during an official race, the right to drive in the following races will be
forfeited.

Appendix-A10.3) Steering and knuckles
10.3.1) Modifications are free. However, since they are an important part of the driving equipment
and drifting on a circuit is expected to have greater inputs than on public roads, parts with
sufficient strength and structure (equivalent to or better than stock) must be used.
10.3.2) Regardless of whether they are stock, modified stock, or external parts, participants
must always personally inspect their vehicles for cracks, deformations, and tightened ordamaged mounting bolts, etc. (arm mounting bolts, etc.) before driving to ensure safety,
and must not expect this to be done by the official vehicle inspection.
10.3.3) No modifications (including the addition of parts) shall be made that could cause the wheel
to separate from the vehicle in the event of damage.

11.5) Wheels
11.5.1) When aluminum wheels are used, it is strongly recommended that they conform to JWL
standards and bear the JWL/VIA mark.
11.5.2) Wheel size must be within the allowable size specified by the tire manufacturer of the tires
used.

F

Appendix-10.2) Suspension
10.2.1) Replacement of suspension arms with fully bolt-on, interchangeable suspension arms ispermitted.
10.2.2) Suspension arms that are cut and welded in shortened or extended lengths must be
fabricated by a responsible manufacturer, and color checks and other inspections must be
performed periodically at the participant's risk.
10.2.3) Parts that could separate the wheels from the vehicle if such parts break must be
fabricated by a responsible manufacturer, and periodic inspections must be performed at
the participant's risk.

11.4) Tire pressure shall be 1.2 kg/cm2 or more.

Appendix-

D1 Regulations

10. suspension and steering
10.1) Suspension Mounting Points
10.1.1) No modifications may be made to the chassis to change the suspension attachment points.
However, suspension members that are separate from the monocoque body may be
modified.
10.1.2) When replacing or modifying suspension members and suspension systems, a written
document describing the purpose of the modification and the modified specification
members must be submitted to D1JO before starting the modification work, and detailed
photographs of the progress and manufacturing status during the work must be submitted
to D1JO during the work to be eligible for official inspection.
10.1.3) When modifying a suspension member, the modification or modification must be made withconsideration so that there is no reduction in strength.

12.3) Hood and trunk lid
12.3.1) The hood and trunk lid may be modified within the scope specified in 11.5) "Hood" of the D1
Vehicle Regulations.
12.3.2) The hood and trunk lid rear hatch must be able to be opened and closed from the outside
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Appendix-C213.5) All potentially hazardous objects (e.g., batteries other than dry batteries, flammable items except
for batteries permitted to be installed in the cabin) must be mounted outside the cabin. Accessories
that are permitted to be installed in the interior of the vehicle are: control devices, safety devices,
communication devices, ballast (if permitted), windshield washer fluid containers, and various
equipment for cool suits.
13.6) The structure must allow a normally seated driver to escape from the cabin in an emergency within
7 seconds from the driver's side door and within 9 seconds from the passenger side door.

D2

Appendix-

14. interior
14.1) Two seats must be provided in the front, complete with dashboard and driver and passenger door
inner trims. Changes to composite or other flame-retardant material products are permitted.

D2

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F2024 D2 Vehicle Regulations

13.4) Bulkheads of car compartments shall be made of solid, fire-resistant material. If new bulkheads
are provided, they must be completely isolated from the vehicle compartment and must be weldedor bolted at short intervals and sealed with a sealant or other means, rather than blind riveted orotherwise temporarily attached.

Appendix-

C2

Appendix-

5413.3) The car compartment must be completely isolated by bulkheads from the engine compartment,
gasoline tank, fuel collector tank, fuel pump and piping, oil tank, gearbox, propeller shaft, andpiping joints, including when undercoating is cut away, bulkhead, floor, center Holes leading to theexterior of the vehicle, such as those at the tunnel, shift lever, etc., must be completely sealed withmetal material or rubber boots. In addition, holes with a diameter of 20 mm or more in the cabinshall not be plugged with aluminum tape or other simple materials.

14.2) Competition vehicles shall not be equipped with any interior trim other than that specified in 14.1),
and the factory floor carpet must be removed.

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Appendix-12.6) Wings and other aerodynamic parts
12.6.1) With the exception of the stock wing, the wing must be contained within the surfaces (notincluding add-ons) that make up the maximum width of the vehicle body. In addition, no partof the wing may exceed the overall length of the vehicle.
12.6.2) The wing shall be attached to the trunk and rear hatch. (Attachment to floor panels or rear
panels is prohibited.)
12.6.3) All parts of the rear wing, canard, and front spoiler must be chamfered and rounded on thecomponent parts except the wing end plates and the mounting surface of the main wing
section.
In addition, the wing end plates of the rear wing shall be attached with tether wires or othermeans to prevent shattering.

13.2) In the case of two-box and hatchback vehicles, etc., where the rear bulkhead is continuous with thefloor surface in a structure that does not form a clear wall shape, the assumed rear bulkhead isthe surface immediately behind the back of the last seatback at an angle equivalent to that surface,
and it is separated from the space by the front bulkhead. However, the conditions in the following
paragraphs must be met.

15. seats
15.1) FIA-approved seats are recommended for the driver's seat.

Appendix-

B

Appendix-12.5) Bumpers, etc.
12.5.1) Exterior body parts (front bumper spoiler, side steps, rear bumper spoiler) must be securely
attached and must not be so attached that they can be easily detached by light contact.
		Bumpers must be securely fastened in at least 4 places (at both ends and in the center) by amethod other than one-touch fasteners.
12.5.2) Front and rear bumpers must be installed when entering the course for official events(qualifying, single race, and pursuit).
12.5.3) Side steps and diffusers must not be on the outermost side (width of the car) of the car.
12.5.4) Air jacks are not permitted.

13. car compartment
13.1) A car compartment is a space separated by a fixed front bulkhead and rear bulkhead.

15.2) Changing the mounting position or replacing the seat rail for the purpose of improving the driving
position is permitted, but the seat rail must be a genuine part of the base car or a part that is set
together with the seat. In addition, if the seat riser of the base vehicle is not used, the installation
method must be in accordance with the JAF Domestic Competition Vehicle Regulations, Chapter 4,
Article 13, 4).

F

A

Appendix-12.4) Glass
12.4.1) Front windscreens must be laminated glass with a certification mark approved for use on
public roads. Cracked or broken glass is not allowed. If cracks or breaks are found during
qualifying or competition driving, the judgment and instructions of the technical committee
members must be followed on a case-by-case basis.
12.4.2) Decals other than official control stickers are not permitted on the front and side glass,
except from the driver's seat to the rear.
12.4.3) Attaching smoke film (including colors other than black and mirror color) to window glass
is prohibited. Attaching transparent film to prevent shattering is recommended.
12.4.4) Side and rear windows must be made of safe and strong materials. In addition, the driver's
and front passenger's side windows must be made of a material that ensures visibility.
12.4.5) Door windows must be rigidly fixed to the door structure or held in place with the samefunctionality as the original door structure to provide occupant protection against forcesfrom inside and outside the vehicle. Auxiliary hardware that secures the upper portion of
the door window panel to the vehicle body for this function is permitted. The hardware mustnot be simplified.
12.4.6) If the rear windscreen is replaced with glass other than that of the base car, metal stays (atleast two from the top to the bottom of the window) must be attached to the body shell orrear hatch in a strong, not simple, manner to prevent it from falling out.
12.4.7) If the rear hatch is replaced with a non-standard lightweight material, standard windshields
shall not be used.

12.6.4) Front spoilers and splitters are permitted within the scope of D1 Vehicle Regulations
11.4.2).

Appendix-

D1 Regulations

and must be securely fastened in at least 4 places including the factory installed hinges.
They must not have a factory-equipped striker function.
12.3.3) Additional fasteners must be of the pin-insertion type. (One-touch push type fasteners are
not permitted.)
12.3.4) The hood opening/closing damper must be removed. 12.3.5) No changes or modifications
to the material of openings with glass (rear (rear) hatches, etc.) are permitted. (except forminor modifications such as the installation of aero parts).
12.3.5) The trunk lid, rear hatch, rear engine hood opening/closing damper and auxiliary opening/closing spring function must be removed, but may be installed on certain vehicles for safety
reasons.

15.3) The same shall apply when changing the front passenger seat.
16. safety belts
16.1) Safety belts must be of the full harness type compatible with the FHR system and of 6-pointtype or more, and must comply with the "Guidelines for Safety Belts in Rally and Speed Event
Competitions" in the Supplementary Rules of Part 4 of the JAF Domestic Regulations for Racing
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16.3) It is not permitted to fasten safety belts to the seat or its support (seat rail). They must be fastened
to the body using the seat belt anchors of the base vehicle or the method described in FIA-J.
16.4) Seat belt anchor positions must be located within the range shown in (Figure 1).
D1 Regulations(Figure 1) 0000000000000000000000000000000000000000000

17. protection of piping
17.1) Fuel, oil, and brake piping must be protected against external damage (heat, flying rocks,
corrosion, mechanical damage, etc.).
17.2) The interior of the vehicle must be constructed so as not to cause fire under any circumstances.

D1 Regulations

16.2) Safety belts that have passed the expiration date on the approved tag may not be used.

16.7) Instead of belt anchor fastening, shoulder belts may be attached to the transverse bar welded tothe backstays on either side of the roll cage. In this case, the mounting method must conform tothat specified in the FIA International Motor Sport Regulations, Appendix J, Article 253.

17.3) Fuel and lubricating oil lines (except brake and clutch systems) must not be routed through joints
when they pass through the cabin.

Appendix-

A

Vehicles. The belts must not be stretched, scratched, or deformed.

A

Appendix-17.4) Fuel, oil, brake, and clutch piping and hoses, wiring, etc. must be secured individually, not cotightened with each other.

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18.3) At least two sidebars must be installed on each of the driver's and passenger's sides, and sidebar
joints may be bolted sidebars that are removable via brackets, but the brackets that attach to thelegs of each side roll bar and main roll bar must be welded to the roll bar.

Appendix-

C1

Appendix-16.6) Depending on the direction of belt tension on the belt anchor, it is recommended to use shear bolts
and eyebolts as shown in Figure 2.

18.2) Only cold-drawn seamless pure carbon steel tubing (D.O.M. copper tubing is permitted) is
permitted for the roll cage and side bars. No alminium material is allowed18.4) The method of mounting the roll cage to the vehicle body shall be in accordance with the JAF Speed
Event Vehicle National Competition Vehicle Rules, Part 3, Chapter 5, Article 1 "Safety Regulations"or D1 Vehicle Rule 12.1).

D2

B16.5) Auxiliary washers must be used for any new installation without using the body structure or the
manufacturer's mounting points. The auxiliary washer shall be made of steel with a radius of 60
mm or more per side and a thickness of 3 mm or more, and the corners of the washer shall be
rounded to a radius of 6 mm or more, or chamfered to a 45° angle of 6 mm or more.

18.5) The mounting position (height) of the side bar should be at least 200 mm above the seat surface
when the driver is in the driving position.

Appendix-

Appendix-

英語訳お願いします18. roll cage
The roll cage must meet the following conditions: D1 Vehicle Regulation 12-1 "Safety Cage" isrecommended, and additional reinforcement members to bring it closer to this condition are permitted.
18.1) The configuration shall be a 6-point roll cage or larger, and for the main roll bar, it shall be φ40mm or larger (wall thickness of 2 mm or more) and may be a bolt-assembled structure that canbe detached and attached. (JAF Speed Event Vehicles: Must conform to Part 3, Chapter 5, Article 1"Safety Regulations" of the Japanese Rules for Speed Event Vehicles.)E
Appendix-

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Appendix-18.6) Where the passenger's helmet may come in contact with the safety roll cage, a cushioning pad
conforming to FIA Standard 8857-2001 Type A (see Technical List No. 23 "FIA-approved roll cage
covering") or SFI 45.1 must be installed.

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Appendix-

19. fire suppression system
All vehicles must be equipped with an in-use and lifetime manual fire extinguisher or piped fire
extinguishing system (recommended).
19.1) Manual fire extinguishers
A manual fire extinguisher is a fire extinguisher whose body can be removed by the driver himself.
Manual fire extinguishers must have a content of 2 kg or more.
19.2) Installation condition
19.2.1) Each fire extinguisher must be mounted so that it is fixed at close right angles (rivets andtie wraps are prohibited) to the front and rear of the vehicle and can withstand a force of
25 times the weight of the extinguisher in any direction, and only rapid-release metal (onetouch fittings) with metal straps Only rapid release metals (one-touch fittings) with metal
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straps are permitted (it is recommended that they be attached in at least two places).
19.2.2) All fire extinguishers must be adequately protected.
19.2.3) Fire extinguishers must be mounted in a position that allows the driver easy access from aseated position.

(Figure 3) 0000000000000000000000000000000000000000000

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B

Appendix-20.2) Battery installation
20.2.1) The battery terminals and the positive terminal of the fuel pump and cell motor shallbe insulated with nonconductive materials. The terminals shall be adequately insulated
to ensure sufficient insulation in the event that they come in contact with other parts ofthe system due to accidents or other reasons. Various types of wiring shall not be fixed
together with piping, etc.
20.2.2) Batteries with volatile batteries installed in the cabin must be dry batteries.
20.2.3) Battery mounting must be able to withstand a force of 25 times the battery weight in all
directions. Bolt-only fastening of floor panels without adequate reinforcement is not
permitted.

Appendix-A

Appendix-

20. electrical system
20.1) Cutoff switch (main power supply)
20.1.1) A cutoff switch (main power circuit switching device) must be additionally installed, andthe control device must be mounted at a designated location inside and outside the vehicle
where the driver can operate it while seated and wearing a belt.
20.1.2) The mounting location of the outdoor control device shall be within a radius of 300 mm
from the lower corner of the windshield support frame (see Figure 3).
20.1.3) A spark sheet (lightning bolt mark) of at least 100 mm per side must be attached at themounting location of the outdoor control device so that its location can be confirmed, andits operating method (PUSH or PULL, etc.) must be clearly indicated.
20.1.4) The activation switches of outdoor control devices and fire extinguishers shall be installed
in close proximity to each other in a position where each can be easily operated separately.

Appendix-

D2

D1 Regulations

19.3) Fire extinguisher inspection
19.3.1) Fire extinguishers must have a fire extinguishing function and the type, other capacity, andtotal weight of the extinguisher must be clearly marked on the container.
19.3.2) Fire extinguishers with a damaged case (outside) or expired extinguishers are not allowed
to be installed.

Appendix-

E
Appendix-

E

AppendixAppendix-

FD220.3) Lamps
20.3.1) All lights (front, tail, brake, direction indicator, etc.) and wipers must be in working order.
20.3.2) All lights are assumed to be in working order at the time of competition vehicle inspection.
If any abnormality is found in the lights due to damage to bumpers, etc. during practiceruns or competition, the technical committee members will decide whether to accept or
reject the car.
20.3.3) Strobe-type or other lights are not permitted during competition.

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2024 D2 Vehicle Regulations

Appendix-F

21. towing hooks
All vehicles must be equipped with towing hooks at the front and rear. The hooks must meet thefollowing requirements
21.1) Conditions when the material is steel
21.1.1) A round bar with a minimum inside diameter of 50 mm (φ50 when mounted on the vehicle
and 50 mm in length) must pass through.
21.1.2) The corners of the inside diameter must be smooth with R.
21.1.3) It must be painted yellow, orange, or red.
21.1.4) The maximum projecting width must be within 100 mm from the bumper hood.
21.1.5) The length of the hook when installed on the vehicle shall not exceed the total length.
However, those that can be detached or retracted while driving on public roads are
2024 D1 RULE BOOK

59

permitted even if they protrude beyond the bumper.
21.2) Conditions when the material is fabric (Figures 4 and 5)
21.2.1) A round bar with a minimum inside diameter of 50 mm (φ50 when mounted on a vehicle
and 50 mm in length) must pass through.
21.2.2) Only towing-specific brackets fabricated for towing are allowed.
21.2.3) Only red, yellow, and blue fabric belts are permitted.

(Figure 5) 0000000000000000000000000000000000000000000

英語訳お願いしますD1 Regulations

D1 Regulations

21.3) Obligation of wearing strength
21.3.1) Under no circumstances shall the hook itself be allowed to come loose from the vehicle
when towing. If the hook falls off when towing, the driver will be subject to a penalty.

A
Appendix-

Appendix-(Figure 4) 0000000000000000000000000000000000000000000

C2

Appendix-

Appendix-

C2

C1

Appendix-

Appendix-

C1

B

Appendix-

Appendix-BA

英語訳お願いしますE

Appendix-

E

Appendix-

英語訳お願いしますAppendix-

D2

Appendix-

D2(Figure 6) 0000000000000000000000000000

Appendix-

F

D1

Appendix-

D1

Appendix-21.4) Obligation to clearly indicate the attachment
point (Figure 6)
21.4.1) Both steel and fabric hooks must be
clearly marked with an arrow sticker
or other means to indicate where thehook is to be attached.
21.4.2) The color of the arrow shall be red.
However, if the body color is red, thearrow shall have a yellow border (10mm wide).

Appendix-F

22. auxiliary devices, etc.
22.1) Driving Auxiliary Devices
The following driving aids are prohibited
unless expressly permitted by the regulations.
ABS / ASR / Traction Control / ESP....
22.2) Driver Radio
Driver communication devices may beinstalled only for voice communication
methods, but must remain legally compliant
for the venue of the competition.
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2024 D2 Vehicle Regulations

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