#36162 9.1.8.I. RADICAL CHALLENGE (SR1/SR3) (REGIONAL ONLY CLASS)

These Regional-only rules are written to give the widest latitude possible for participation
while staying within manufacturer performance limits; but not requiring specific items
like sealed engines.
If any exploitations raise costs significantly, participation drops due to increased need for
competitive advances, or the class eventually requires a more focused balance of
performance; participants should not expect their investment/research/modification to be
protected at the expense of the class. (I.e., modifications beyond factory performance will
likely create rules which render your vehicle ineligible/non-compliant at a later date.
Competitors should choose their modifications and investments in those modifications
wisely.)
A. Vehicle Manufacturer
Radical Motorsport Ltd Tel: +44 1733 331616
24 Ivatt Way Business Park Fax: +44 1733 264959
Westwood, Peterborough PE3 7PG Email: sales@radicalmotorsport.com
United Kingdom Website:
www.radicalmotorsport.com
B. Radical Sports Racer 1 (SR1)
A class for the Radical SR3 models RS, RSX, XX and XXR using the Suzuki 1340cc engine
with Fuell Cell and Safety Equipment conforming to the GCR.
C. Radical Sports Racer 3 (SR3)
A class for the Radical SR3 models RS, RSX, XX and XXR using the Suzuki 1500cc engine
with Fuell Cell and Safety Equipment conforming to the GCR.
2. General Modification Rules
A. Radical Challenge Classes are Restricted Classes. Competitors are not permitted to depart from
factory specifications and any allowable modifications, changes, or additions are as stated
herein. There are no other exceptions.
B. An authorized addition, modification, substitution, or removal may not perform a
prohibited function/may not serve any other purpose.
C. Replacement parts must be sourced/supplied by Radical Motorsport or its
dealer/distributor network, fitted as supplied, in their original position and only to their
designated edition of a specific model.
D. Modifications and alternate parts specified in the Radical Global Scrutineering Guides are
permitted.
E. It is permitted to perform routine maintenance and repairs if existing parts are in no way
modified and replacement parts are official Radical parts.
F. GCR General Technical and Safety Specifications
Vehicles must meet all requirements of GCR Section 9.3 and 9.4.5 for Sports Racers,
except when requirements of the Radical Cup Rules, Technical Regulations and
Scrutineering Guides mandate or allow different choices. (E.g., the Radical high-intensity
rain light or location of the master switch.)
G. The entrant has the burden of proving that the vehicle conforms to these Rules by the
required documentation as noted below. The required documentation should be considered
as an extension of these Rules.
a. Current-year Radical Cup Technical Regulations
b. Current-year Radical Cup SR1 or SR3 Scrutineering Guide appropriate for the class entered.
c. If using unsealed engine/gearbox, the following is required:
l1 The official manufacturer service documentation for the eligible engine if ever
available to the consumer from the manufacturer.
ll1 Other official manufacturer documentation, such as the owner’s manual, shop
manual, parts catalogs, technical bulletins, sales & marketing literature may be
provided as supporting information.
lll1All manufacturer documentation must be for non-competition purposes.
d. The entrant of a protested vehicle has the burden of proving that the vehicle
conforms to these rules by the required documentation. If the required
documentation does not include sufficient information on a protested item or
specification, the burden shifts to the protestor to prove the equipment or
specification illegal.
3. Vehicle Documentation
A. Vehicle Logbooks
Vehicles shall have and utilize the SCCA logbook requirements and procedures in GCR 9.2.1.
B. Homologation Requirements
Radical cars are considered “alternate” design standards for roll structures under SCCA
standards for Sports Racers and will require homologation. The homologation may be
procured by reaching out to the SCCA Technical Department at roadracing@scca.com
Cars that have previously been issued logbooks and have Homologation Certificates
(E.g., for P2) may satisfy this rule by presentation of said certificate or a copy thereof.
The existence of a Homologation Certificate or letter of exception from the Road Racing
Department is not conclusive evidence of rules compliance.
4. Data Collection Devices
A. Driver Data Collection - Data collection devices are considered to be instrumentation and are
therefore allowed as long as they serve no other purpose.
Note: Radical Cup only allows an official single data system.
B. Official Data Collection - The Club Racing Board uses SCCA data acquisition devices to assist in
performance balancing. Race Data Technicians assist in placing the SCCA data acquisition devices
at events. If selected, drivers’ participation is not optional and is not protestable. The data
collected will not be used for compliance purposes. All cars carrying an SCCA data collection
device shall report to impound immediately after their sessions.
5. Safety Requirements
A. Driver Restraint System
Vehicles shall have restraint systems (including arm restraints) meeting GCR 9.3.18
B. Driver Safety Equipment
All required driver’s safety equipment must be worn at all times while on track. The
participant agrees that the participant bears the ultimate responsibility at all times to
ensure the safety of participant’s driver’s safety equipment, and compliance with all SCCA
rules, regulations, and agreements, including but not limited to those contained in the
GCR.
a. Driver Safety Equipment (Helmet, H&N restraint, suit, gloves, shoes, etc.) must comply
with GCR 9.3.19
C. Seats
Seats must be securely mounted, and the seating position of the driver shall be so that
the headrest is fitted in line with the helmet, not the neck.
a. Any seat specific to model of car is permitted.
b. A single seat may replace twin seat.
c. It is highly recommended the wrap-around style headrest be fitted.
d. Padding must be attached to the appropriate side bar (E.g., left or right hand-drive
chassis).
e. Foam inserts are permitted. FIA Appendix J, Article 257A standards are
recommended for material, location and sizes.
f.Competitors are reminded that any modification to seats or headrests supplied by
Radical Motorsport, or materials not approved by Radical Cup Technical Rules or
Scrutineering Guides is unauthorized and is at the sole risk of the Entrant/Competitor.
D. Hand Controls
Hand controls may be approved on a case-by-case basis. Such approval shall be in
writing from the Road Racing Technical Manager and shall be in the driver’s possession
at all competitions.
E. Fire System
All cars shall be equipped with an On-Board Fire System meeting GCR 9.3.22
6. Cameras
A. All cars competing at Regionals must have a forward-facing camera that is recording at all times
while on track and provides a clear horizontal field of view of the cars and track ahead. The
cameras may be mounted either inside the car, or on the body. If video is needed as part of an
investigation of an incident, a competitor’s video of the full unedited session may be requested
by race officials regardless of whether or not said competitor was involved in the incident.
Failure to provide such video may result in penalties. Forward-facing cameras are recommended
at all other SCCA-sanctioned events. The video format must be a digital file so it can be viewed
in an MS Windows compatible viewer.
B. The mounts for video / photographic cameras shall be of a safe and secure design. The body of
the camera or recording unit that weighs more than 8 oz shall be secured at a minimum of 2
points on different sides of the camera body. Suction cups or elastic mounts are not permitted. If
a tether is used to restrain the camera, the tether length shall be limited so that the camera
cannot contact the driver.
7. Cool Suits
Cool suits are allowed. Water tank mounts shall be of a safe and secure design.
8. Coolant/Fluid Overflow Tanks/Fluids
A. There shall be no visible fluid leaks.
B. Any oil or oil additive may be used. Oil additives are defined as: Any liquid or particulate
compound(s) delivered into the engine via the engine oil for the purpose of friction/temperature
reduction, and/or metal surface conditioning (i.e. PTFE resins (Teflon, “Slick-50”), Molybdenum
Disulfide, etc.).
C. Cooling systems shall be equipped with coolant catch tanks to prevent the spillage of coolant
onto the racing surface. An oil catch tank with a minimum capacity of one U.S. quart may also
serve as the coolant catch tank, except for cars that are equipped with working OEM
pressurized coolant reservoirs, which may use an additional catch tank. If the coolant catch
tank is separate from the oil catch tank, the coolant catch tank shall have a minimum capacity
of one U.S. pint.
9. Chassis
A. Bracing and Bars
The Radical Motorsport Crashbox must be installed and free of damage. Side impact bars
must be installed. Tow hooks must be installed on each end of the car.
The Radical Cockpit Safety Structure is not permitted to be installed at this time.
B. Hoses, Wiring, Cabling
Clips and fasteners may be installed within the cockpit to secure accessory wiring and
cabling for permitted devices. (E.g., Flagtronics, video camera, data acquisition.)
C. Ride Height
a. No part of the car other than skid blocks or breather tube, may be less than 40mm above
a horizontal plane from level ground.
b. Ground clearance shall be measured at a tire pressure of 28 psi, without driver. Air or
nitrogen may be added to check ground clearance.
c. Ground clearance measurement allowance should be made for cars with bodywork, chassis
or suspension damage which occurred without time for repairs. (E.g., during the session or
in extreme cases, the event weekend.)
D. Repairs
All repairs must comply with industry standard methods. Such repairs may not result in a
competitive advantage (e.g., significant change to weight, suspension control, power,
stiffness etc.) as compared to the standard part(s).
Radical Motorsport Ltd. cautions, “Any chassis repair work not carried out by Radical
Motorsport Ltd is unauthorized and is at the sole risk of the Entrant/Competitor. Radical
Motorsport Ltd accepts no liability or responsibility for injury or death as a result of
unauthorized repairs.”
10. Bodywork
A. Mirrors shall provide driver visibility to the rear of both sides of the car.
B. Tape may be used to cover bodywork fasteners, or for temporary repair.
11. Graphics, Numbers and Markings
A. Advertising and graphics (names, symbols and logos) may be displayed on cars provided they are
in good taste, adhere to the SCCA welcoming environment statement and do not interfere with
identification marks and SCCA logos.
B. Cars in a condition that prevents proper inspection/evaluation of vehicle condition (too dirty,
show substantial bodywork damage, structurally damaged), shall not be approved for
competition.
C. Identification Markings
Each car shall carry identification markings (Numbers, class, stickers, etc) conforming to
GCR 9.3.29 and any markings required by the Supplemental Regulations.
a. Graphics, numbers (style/font/size) etc. as used in the current-year Radical Cup Style
guide are permitted, even if they do not meet GCR 9.3.29 specifications.
12. Cooling
A. Radiator ducting may be taped off or have mesh screen installed to control temperature.
B. Water and oil may be pre-heated.
C. To prevent bodywork damage to the sidepod, ‘Hanging’ radiators with brackets are
permitted.
D. To prevent damage from friction, rubber or sleeves may be added to oil and water lines.
13. Intake
The airbox may be covered by heat resistant tape or foil.
14. Engine and Drivetrain
A. Engine
Engines for SR1 and SR3 may only be those specified in the Radical Global Scrutineering
Guides, only modified within the limits of the Radical Global Scrutineering Guides,
sealed by Radical (RPE) or modified only within the limits below:
a. Engines may be rebored to the manufacturer’s 1st standard overbore, not to exceed 0.020”
(0.508 mm). Sleeving is allowed to repair to the standard bore. Only OE-type standard or 1st
overbore pistons of the same configuration and of the same or greater weights are
permitted. No interchange between cast and forged pistons is allowed.
b. Heads and/or blocks may only be trued (shaved) to the service limit specified in the factory
workshop manual. If a service limit is not specified, then the head and/or block may not be
trued (shaved) and must be used at the specified original dimension.
c. Camshafts are not considered normally expendable items, therefore they must not only
meet original specifications but they must be from the original manufacturer. Aftermarket
units are not allowed.
d. Updated parts, replacement parts, or any other changes by the manufacturer documented
in the parts catalog or other manufacturer documentation as superseding the original part
number used when manufactured are considered to be standard parts.
e. Alternate parts (parts that may fit due to common platforms) listed in a factory parts
manual are not authorized unless their use is specifically referenced in the factory service
manual or in a service bulletin for the specific model and/or option package.
B. Engine Control Unit (ECU)
ECU heat shielding is permitted, but it must not hinder removal when requested.
C. Transmission
The only permitted adjustment to the drive ratio is by changing the sprockets/gears
supplied for a specific model by Radical Motorsport.
15. Exhaust System
Mufflers may be added to the exhaust system, minimum modification required to attach
any noise-reduction device is permitted. While the SCCA does not restrict the type/brand
of device, competitors should note that Radical Cup noise-quieting products must be as
supplied and unmodified.
16. Suspension
A. Bushings
The make/brand of suspension bushings are open, but the specifications (E.g., materials,
dimensions and type) are not.
B. Dampers (Shocks)
Restrictions on model/spring rates must align with the Radical Global Scrutineering
Guides.
a. Brand of spring is open, but specifications (dimensions/rate) are not.
C. Anti-Sway (Roll) Bars
Front and Rear bars may be any of the sizes/rates specified for use on the specific model
Radical.
17. Brakes
A. Cockpit adjustable bias adjuster is permitted on SR3 RS and RSX cars. The adjuster does not
have to be supplied by Radical Motorsport.
B. Brake duct grills may be fitted or removed.
C. Tape may be used to regulate the amount of air flowing through brake ducts.
D. Extra brake cooling may be fitted to cars based on specific track conditions. This
allowance must be noted in event Supplemental Regulations.
18. Steering
If supplied by Radical Motorsport for the model edition, steering wheels of a different
diameter are permitted.
19. Wheels
Wheels must be as supplied for that model edition by Radical Motorsport or as permitted by
the Radical Global Scrutineering Guides.
20. Tires
The number of tires used per weekend, a spec tire and other restrictions may be mandated
by Event Supplementary Regulations.
21. Fuel
The recommended fuel is Sunoco 260 GT. If that fuel is not available, competitors may use
the closest fuel available locally not exceeding 100 octane. The use of leaded fuels or other
additives is prohibited.
A. Heat shrink, insulation, or rubber sheathing may be added to fuel lines to prevent
damage from friction.
B. Fuel Cell
A fuel-cell (Container, rubber bladder, explosion-suppressing foam) meeting FIA FT-3 or
higher or SFI 28.3 shall be used. It is recommended that the standard Radical 50-liter fuel
cell be used, and competitors are cautioned that in the Radical Cup series – the Radical
Fuel cell is mandatory and must be replaced upon expiration.
C. Fuel Testing
Cars shall be equipped with an accessible sampling port/valve/device located in a fuel
line between the fuel tank or fuel cell and the injection system to allow safe acquisition
of a fuel sample. The sampling port/ valve/device will be installed and used by the
competitor to obtain the sample without fuel leaking, spraying or squirting. Siphoning of
fuel directly from the fuel tank or fuel cell or removing a hose or line is not allowed.
a. The Radical Fuel testing ‘T’ piece plus a Radical dry break valve fitted to the fuel line is
recommended.
22. Electrical System
A. Master Switch
All cars must have either a master switch meeting GCR standards for Sports Racers or the
standard Radical master “off” switch. It shall be marked by the international marking of a
spark in a blue triangle located on the outside bodywork as near to the master switch as
possible.
B. The addition of ducts and duct work to cool the starter motor and alternator is permitted.
23. Weight
A. Minimum Weight:
The minimum weight, specified with driver, exactly as they come off the race circuit, at the
conclusion of any race or qualifying session is as follows:
a. SR1: 1,587 Lbs.
b. SR3: 1,587 Lbs.
B. Ballast:
Ballast may be added to meet the minimum weight requirement provided it is securely
mounted to the chassis within the cockpit and serves no other purpose.
24. Battery
The make, model number, and size of the battery may be changed but not its voltage or
location. Battery must be capable of repetitive starts.
A. Cars using a lithium-ion battery must display the green and black Lithium Battery decal near
the master (kill) switch. Decal can be purchased through my.scca.com
SCCA ELECTRIC TOURING (ET) RULES DRAFT
SCCA ELECTRIC TOURING – 120122a
25. Lights
A. Headlights
It is recommended that the Radical-supplied front lighting kit is retained and turned on in each session.
B. Brake Lights
Brake lights must be fitted, in working order, and must not be wired in a way that allows them to be
switched off or have the signal delayed.
C. Rain Light
Cars must be equipped with rain light(s) clearly visible from the rear. The rain light(s) must be turned on
when directed by the Race Director or Chief Steward
a. When originally equipped, the Radical high intensity LED central Rain Light may be used.
b. Cars not equipped with the Radical high intensity LED central Rain Light, a red rain light meeting FIA
Standard 8874-2019, Technical List No. 76, is required. This light must be mounted approximately on the
centerline of the car. The rain light may strobe.
26. Seals
It is recommended that all seals mandated by Radical Cup are in place, but not mandatory.
A. Engines, including integral gearbox and clutch units sealed by Radical Performance Engines (UK) or authorized
Radical Engine Rebuilders for Radical Motorsport Ltd. Shall not be disassembled/have their seals broken by
SCCA Inspectors/Officials.
a. Reserved for a bond process, posted by the protestor, covering total expenses for a sealed engine to be
inspected by Radical Ltd./authorized agent.