FE + F5 + SRF + FE 2 at Buttonwillow Raceway Park

In GCR section 9.1.1.I.13, make changes to wet tires as follows:
“Front: P/N: 44195 W3, 22.0 X 7.5-13 WET
Rear: P/N: 44217 W3, 22.0 X 9.0-13 WET”

In GCR section 9.1.1.I.8.f, change as follows:
"Anti-roll bars (sway bars) may be run disconnected, but not removed. One anti-roll bar link may be removed
from the front, rear, or both ends of the chassis for safety reasons, but no modification of the link or attachments
is permitted."

In GCR section 9.1.1.I.6, add a new subsection as follows:
"k. Enterprises bubble tail P/N: WM138014 is allowed for both FE and FE2."

In SRF, GCR section 9.1.8.E.1.V, add the following:
"ii. Dash Windscreen Kit, P/N 1180103 or P/N 180102, is allowed."

In GCR section 9.1.1.I.13, make changes as follows:
"Tires must run in sets of 4 as stated below:
DRY
American Racer (until 05/31/2019)
Front: P/N: JE3C3, 22.0 X 8.0-13S
Rear: P/N: JE3MA, 22.5 X 10.0-13S
or
Front: P/N: JFEC3, 22.0 X 8.0-13S
Rear: P/N: JFEMA, 22.5 X 10.0-13S
Hoosier (beginning 01/01/2019)
Front: P/N: 43272, 22.0 X 8.0-13 FE
Rear: P/N: 43312, 22.0 X 10.0-13 FE
WET
American Racer (until 05/31/2019)
Front: P/N: JWWC3: 22.0 X 8.0-13
Rear: P/N: JWWMA, 22.5 X 10.0-13
Hoosier (beginning 01/01/2019)
Front: P/N: 44195 W3, 22.0 X 7.5-13
or P/N: 44196 W3, 22.0 X 7.5-13
Rear: P/N: 44217 W3, 22.0 X 9.0-13"

In the F500 engine table, change the weight as follows:
Honda CBR600RR (03-13): "875 900"
In the F500 engine table, change the weight as follows:
Suzuki GSXR600 (03-13): "875 900"
In the F500 engine table, change the weight as follows:
Yamaha R6 (03-13): "875 900"

In FE, GCR section 9.1.1.I.13, change as follows:
"WET
Hoosier
Front: P/N: 44195 W3, 22.0 X 7.5-13
or P/N: 44196 W3, 22.0 X 7.5 8.0-13
Rear: P/N: 44217 W3, 22.0 X 9.0-13"

In SRF, GCR section 9.1.8.E.1.V.s delete section in its entirety as follows and re-letter as follows:
"It is forbidden to regroove tires."
In SRF, GCR section 9.1.8.E.1.X.f, add new sections as follows:
"Tires:
Dry:
Front – Hoosier P/N 46340 P185/60ZR13
Rear – Hoosier P/N 46350 P205/60ZR13 SRF
Wet:
Front – Hoosier P/N 46100 P185/60R13 H20
Rear – Hoosier P/N 46105 205/60R13 H20
1. It is forbidden to regroove tires.
2. The use of tire warmers or cooling methods other than natural air convection or conduction is
prohibited. The penalty for violation will be the loss of qualifying times and/or the disqualification of race
results."

In FE, GCR section 9.1.1.I.8.b, add the following:
"Front Springs: 600 lbs. ±25 lbs. Faulkner Part # WM203008 or Hypercoil Part # WM203011
Rear Springs: 1000 lbs. ±25 lbs. Faulkner Part # WM203009 or Hypercoil Part # WM203012
or
Front Springs: 800 lbs. ±25 lbs. Hypercoil Part # WM203013, Silver
Rear Springs: 900 lbs. ±25 lbs. Hypercoil Part # WM203014, Silver
Effective June 1, 2020, Part # WM203013 Front and Part # WM203014 Rear will be required for FE2 and
optional for FE."
In FE, GCR section 9.1.1.I.13, add a new section as follows:
"e. The use of tire warmers or cooling methods other than natural air convection or conduction is
prohibited. The penalty for violation will be the loss of qualifying times and/or the disqualification of race
results."
In FE, GCR section 9.1.1.I.15, change the weight as follows:
"The car shall weigh 1260 1270 lbs. minimum, including the driver."
In FE2, GCR section 9.1.1.I.16.h, change the weight as follows:
"Weight The car shall weigh 1250 1270 lbs. minimum, including the driver."

In SRF, GCR section 9.1.8.E.1.E.a, change the minimum weight as follows:
"Front 35 32 lbs."

In SRF, GCR section 9.1.8.E, make changes as follows:
"SPEC RACER FORD 3 (SRF/SRF3)"
In SRF, GCR section 9.1.8.E.1, make changes as follows:
"SPEC RACER FORD 2 (SRF) Regional Only Class"
In SRF, GCR section 9.1.8.E.2, make changes as follows:
"SPEC RACER FORD 3 (SRF3)"
In SRF, GCR section 9.1.8.E.2.A, make changes as follows:
"It is the intent of the SRF3, GEN3 a Ford 1.6L conversion, to update the current 1.9L SRF drivetrain for
class longevity. SRF and SRF3 shall compete side by side, for respective points and championships."

In SRF, GCR section 9.1.8.D.1.W.l, change as follows as approved by BoD on 9/12/2023:
"This rule supersedes GCR section 9.3.32.B.2 effective 1/1/2024 through 12/31/2024."

Effective 1/1/2020, in FE, GCR section 9.1.1.I, make changes as follows:
“I. FORMULA ENTERPRISES (FE2/FE) PREPARATION RULES
1. FORMULA ENTERPRISES 2 (FE2) FE2 2.0L MZR
A. Definition
FE’s with the Mazda new optional 2.0L MZR engine will be classed as “FE2” and will use the class
designation FE2. The FE2 will run as a parallel class to the FE (2.3L engine) class. When SCCA Enterprises
is unable to service the FE’s 2.3L engines, the 2.0L MZR engine will become the only Major’s or National
Class competition engine, at a certain time “TBD” the FE 2.3L will a become Divisional or Regional Only
Class Car.
2018 competition season going forward the The Mazda Optional 2.0L MZR engine can be used in all SCCA
events. It shall run under all FE Preparation rules excepted as noted below:
a. 2.0L MZR may be run with an Elite 5SPD or a Complete SADEV 6SPD transmission Kit
Must use the following:
b. 2.0L only Intake Manifold Part # WM30106
c. Throttle Body Part # WM591930-Jenvey
d. PE ECU Kit Part # 1192012
e. Nippon-Denso Alternator Part # WM902127
f. Oil Filter Adaptor Part # WM301050 & Oil Filter Part # G301022
g. PCV Valve Part # WM391502
h. Weight The car shall weigh 1250 lbs. minimum, including the driver.
i. 16” MAZDA logo on each side of the engine cowling and the Mazda wing & name logo on the front
center of the nose cone. These are mandatory decals.
j. 2.0L MZR required Spark Plug Part# ND ITV 24
2. FORMULA ENTERPRISES (FE) – Regional Only Class
A. Definition
One design, fixed specifications, open cockpit, single seat Formula car with the Mazda 2.3 engine. Cars
are packaged and sold by SCCA Enterprises (Enterprises). All replacement parts are supplied through
Enterprises and shall be official Spec Formula Car parts except where noted in J.4. No modifications may
be made to any part or system unless specifically permitted in these rules. The 2.3L FE cars will continue
as a Runoffs eligible class through 2019.
B. 2. Safety Requirements
Car will be delivered from the manufacturer with approved safety equipment. Replaced items shall be
supplied through SCCA Enterprises, except safety harnesses may be replaced by any other that conforms
to GCR Section 9.
C. 3. Vehicle Configuration
All cars to GCR section 9 with the following exceptions: Section 9.3 Accumulators.
D. 4. Maintenance and Repairs
It is permitted to perform routine maintenance and repairs as long as existing parts are in no way
modified and replacement parts are official Enterprises Formula Car parts. If any official Enterprises’ seal
is broken, lost by accident or intent, the procedures outlined under I.18., shall be followed. Parts and
materials with an Enterprises part number having the prefix “WM10” are considered to be unrestricted,
providing their dimensions and materials are comparable. No other parts are to be considered
“unrestricted” except where specified.
E. 5. Chassis
NO MODIFICATIONS ALLOWED except as noted in these rules.
a. All cars shall use the stock, as delivered by Enterprises, wood floor of 6mm, with an allowable
deviation of 3 mm across the surface for wear.
b. Seats are free. Panels inside the cockpit may be attached to the frame as long as the points of
attachment are no closer than 6 inches apart. No welding or gluing of the seat to the structure of
the car is allowed.
Definition of cockpit is: area between the front roll hoop and rear roll hoop.
c. Painting or powder coating of the chassis is allowed.
d. Enterprises foot drop box part # WM180020J may be installed.
e. Enterprises impact attenuator part #WM180023 (crush box) shall be installed.
f. Transponder must be used per SCCA Enterprises Technical Bulletin 002-2016.
F. 6. Bodywork
NO MODIFICATIONS ALLOWED (except as specified). If any seal, label, stamp is missing the parts must be
returned to Enterprises for resealing.
a. Bodywork shall remain unmodified with the exception of holes for a slave or jumper battery plug,
trackside beacon receiver, and tow hooks. All repair work must match original body dimensions and
contours.
b. Bodywork fasteners are free.
c. The car may be painted any color(s), except primer.
d. It is required that all cars display the official sponsors of Enterprises decals and locations as
specified by Enterprises.
e. Radiator screens are allowed and recommended.
f. All aerodynamic devices shall be used as delivered: i.e. wings, body winglets. No modification to
mounting location or holes.
g. T The front wing main plane, front wing secondary elements, front wing support mounts, and front
wing endplates must be used and mounted as delivered from Enterprises. Any modification to these
parts, except as specifically noted herein, is strictly forbidden. The main wing plane angle is zeroed
on the rear upper aft transmission surface measured with a suitable angle gauge, i.e.: digital level on
the top main plane 2 inches outward from the nose box mounts. It must meet a minimum
measurement of negative .5 degrees (angled down in the back) and a maximum measurement of
positive 2.5 degrees (angled up in the back). It is acceptable to shim the main plane to obtain this
measurement. Wicker bill (Gurney flaps) are permitted as an option for installation on the trailing
edge upper surface of the front wing secondary elements only, not the wing main plane. They must
be attached in a secure fashion, without modification to the wing element except for mounting
hardware. Total height is .500”. Maximum number of mounting locations on front flaps is 2 on each
flap and maximum hard- ware size is #8 (.156). Gurney flaps, where attached, shall be 90 degrees
and parallel to the upper surface of the wing element and no taper or “saw toothed” Gurneys are
permitted.
h. The rear wing and its related mounting components are to be used and mounted as delivered.
Any modifications, except as specifically noted herein, are strictly prohibited. The lower plane angle,
zeroed on the rear upper aft transmission surface, measured with a suitable angle gauge. i.e.; digital
level on the top surface of the lower rear wing must meet a minimum of –3.0 degrees (angled down
in the back) and a maximum of +2.0 degrees (angled up in the back). It is acceptable to adjust the
lower rear element to meet these requirements. The upper rear wing element may only be adjusted
within the parameter of the endplates and wing adjusters as provided from Enterprises. No
additional holes may be added. Wicker bill (Gurney flaps) are permitted as an option for installation
on the trailing edge upper surface of the wing element. They must be attached in a secure fashion,
without modification to the wing element except for mounting hardware. Total height is .250” on
one or both elements. The Gurney flap only, may extend beyond the parameters of the end plate.
Maximum number of mounting locations is 5 and maximum hardware size is #8 (.156). Gurney flaps,
where attached, shall be 90 degrees and parallel to the upper surface of the wing element and no
taper or “saw toothed” Gurney are permitted.
i. The stock headrest may be modified or replaced with any headrest meeting GCR section 9.4. The
stock lateral bolsters may be modified or removed.
j. Enterprises windscreen P/N: WM137000 is allowed.
k. Enterprises bubble tail P/N: WM138014 is allowed for both FE and FE2.
G. 7. Engine and Drivetrain
a. Engine
1. NO MODIFICATIONS ARE ALLOWED EXCEPT WHERE SPECIFICALLY AUTHORIZED WITHIN THESE
RULES. This includes all fuel injection and engine management components, including exhaust,
cooling, electrical and lubrication systems. All systems are subject to test procedures and must
conform to OEM specifications as stated and supplied by Enterprises. All fluids, except fuel, are
unrestricted.
2. Enterprises seals on the engine, and other components shall remain in place at all times. All
engines shall be rebuilt, checked on an engine dynamometer, and sealed through Enterprises.
3. Engine maintenance, which is permitted, includes the replacement, but not modification of
external engine and engine systems parts.
4. There are six (6) seals on the engine. Two (2) on the timing cover, two (2) on the top of the
valve cover, and two (2) on the oil sump. They may not be removed or tampered with.
5. All rubber oil lines may be replaced with braided metal-covered (Aeroquip type) lines. Hose
clamps may be installed on the rubber oil lines.
6. Intake manifold: No modifications are allowed. Absolutely no porting or the addition of material
is allowed. No coating or painting is allowed on the exterior or interior of the intake manifold.
7. Only Engine Control Units (ECU) manufactured by MBE or Performance Electronics are
permitted. Modification of the ECU, ECU program, wiring or sensors is prohibited. ECUs are
password protected.
8. The flywheel weight is a minimum of 2.6 pounds for the Enterprises supplied flywheel. No
modifications to the flywheel with the exception of normal resurfacing for clutch wear are
allowed.
9. No modification to the crankshaft dampener is allowed.
The following parts must be used:
10. Clutch: Enterprises supplied clutch and flywheel contained in kit #WM701000A, Piston
#WM701004A, Throw out bearing #WM701006A, Small O-ring #WM1010405, Large o-ring
#WM1010406, Flexplate and Ring Gear # WM1101053.
11. Spark Plugs, Part # NGK PTR5F-11, NGK TR5AI-13, or Motorcraft # AGSF32FEC.
12. Fuel Injectors: Part # WM591929
13. Throttle Body: Part # WM591930 or WM591930-Jenvey (used with PE ECU only)
14. Fuel Filter: Any 10-micron fuel filter may be used as long as it performs no other purpose than
to filter fuel.
15. Air Filter: Part # WM301020
16. Exhaust systems may be thermal coated or wrapped.
17. A heat shield between the engine block and the exhaust system is recommended for the
purpose of protecting hoses, shifter cable, and wiring from the heat of the exhaust.
18. An Enterprises muffler kit part #WM1131046 (with packable muffler #WM301040A) or muffler
kit part #WM1131047 (with no pack muffler #WM301063) is required. The muffler may not
extend beyond the back of the transmission. An additional muffler may be added to accompany
the stock muffler as needed to meet sound requirements.
19. An optional air to oil cooler is allowed. The maximum core size is 13 inches wide by 6.5 inches
high. No water to oil heat exchanger is allowed.
20. An optional Enterprise alternator kit is allowed, Part # WM1100101
b. Transmission
1. The ELITE 5 speed or SADEV 6 speed sequential transaxles supplied by Enterprises are the only
permitted transmissions. No internal or external modification (including lightening) other than
normal racing repair or as noted below:
a. “SADEV Only” when tested and proven “Flat shift” may or may not be used, competitor’s
choice, only approved method is PE Electronics ECU with SADEV shift sensor. Optional “Auto Blip
Kit” may also be used when tested and proven.
b. “SADEV Only” 1-2019 SADEV gear box will be run as a sealed unit, can be serviced and
inspected by CSR or approved SADEV service center. At event damage can be inspected /
repaired / resealed if necessary, by CSR or approved personnel.
2. ELITE Transmission servicing, replacement of internal components is permitted by the
competitor with the following exceptions:
a. All components must be ferrous metal, except for bearing retainers and bearing cages.
b. Components manufactured by alternate manufacturers are permitted. Replacement
components must be direct replacements to the original components. Absolute minimum
weights are listed below.
3. The rear cover plate may be manufactured or remanufactured using aluminum.
4. Only approved ratios:

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

In the F500 engine table, change the restrictor as follows:
Honda CBR600RR (03-13): "29 28mm Flat Plate Intake Restrictor"
In the F500 engine table, change the restrictor as follows:
Suzuki GSXR600 (03-13): "29 28mm Flat Plate Intake Restrictor"
In the F500 engine table, change the restrictor as follows:
Yamaha R6 (03-13): "29 28mm Flat Plate Intake Restrictor"
Table 1
Car Engine Wheel
Width (in)
± .060
Aero Transmission Weight Notes
USF2000
Tube
Frame
2.0 Liter
Mazda MZR
See notes See notes See notes See
notes
Car must comply with the 2012
Pro USF2000 rules. Competitors
must have the current rules in their
possession and present them upon
request. The following sections of
the 2012 Pro rules do not apply:
14.1.1 thru 14.1.4; 14.12.2 thru
14.12.13; 14.13.1; 14.13.2; 14.13.5;
14.18 in its entirety; 14.19 in its
entirety; 14.27 in its entirety; 13.34 in
its entirety

In SRF, GCR section 9.1.8.E.1.X.h, make changes as follows:
"Shock Absorbers: Penske shock P/N 280396 with spec valving shall be used as a sealed
assembly with no modification of any kind. If shock seals are damaged in any way, the
shock must be sent to an authorized SCCA Enterprises service center for verification and
resealing at the competitor’s cost. Beginning
05/01/2020 2019, the SCCA Enterprises bump rubber stop P/N 280407 may be used as
delivered with no modification of any kind; if used, maximum of one bump rubber stop per
shock. Effective 05/01/2020, only the SCCA bump stop P/N 280407 may be used as
delivered with no modification of any kind; if used, maximum of one bump stop per
shock.”

In GCR section 9.1.1.I.2.H.b, change as follows:
"Effective June November 1, 2020, Part # WM203013 Front and Part # WM203014 Rear will be required
for FE2 and optional for FE."

In FE, GCR section 9.1.1.I.2.F., clarify wording as follows:
"g. Wicker bill ( Gurney flaps) are permitted as an option for installation on the trailing edge upper
surface of the front wing secondary elements only, not the wing main plane.
h. Wicker bill ( Gurney flaps) are permitted as an option for installation on the trailing edge upper surface
of the wing element."

Thank you for your letter. After reviewing the response to the WDYT published in the May 2020 Fastrack
Minutes, the Club Racing Board does not recommend this change.

Thank you for your letter. Please see the response to letter #28359 in this Fastrack.

Thank you for your letter. Please see the response to letter #28359 in this Fastrack.

In GCR section 9.1.1.I.2.F.g, clarify as follows:
"Gurney flaps are permitted as an option for installation on the trailing edge upper surface of the front wing secondary elements
only, not the wing main plane. They must be attached in a secure fashion, without modification to the wing element except for
mounting hardware. Total height is Only .500" +/- .030" flaps are allowed."
In GCR section 9.1.1.I.2.F.h, clarify as follows:
"Gurney flaps are permitted as an option for installation on the trailing edge upper surface of the wing element. They must be
attached in a secure fashion, without modification to the wing element except for mounting hardware. Total height
is Only .250” +/- .030" flaps are allowed on one or both elements."

In the F500 engine table, update as follows:
"Suzuki GSXR600 (03-13 19)"

In SRF, GCR section 9.1.8.E.1.I, change as follows:
"NO MODIFICATIONS ALLOWED. Only SCCA Enterprises sealed Penske shocks P/N 280396 shall be used. Only front spring P/N
280387 or P/N RO28037 shall be used. Only rear spring P/N 280390 shall be used. Effective May 1, 2020, o Only the SCCA Bump
Stop P/N 280407 may be used, with no modification of any kind. Bump stops are optional. If used, only one bump stop per shock
is permitted."
"All shock absorbers must be sealed by SCCA Enterprises. Prior to sealing, the shock absorbers will shall be rebuilt
by SCCA Enterprises or its authorized rebuilders."
In SRF, GCR section 9.1.8.E.1.X, change as follows:
"c. Rear Springs: 412-429 lbs./in Enterprises P/N 280390 or previous Enterprises supplied part (ex.RO280388 or RO280389)."
"h. Shock Absorbers: Only the Penske shock P/N 280396 with spec valving shall be used as a sealed assembly, with no
modification of any kind. If shock seals are damaged in any way, the shock must be sent to an authorized SCCA Enterprises
service center for verification and resealing at the competitor’s cost. Effective May 1, 2020, o Only the SCCA Bump Stop P/N
280407 may be used, with no modification of any kind. Bump stops are optional. If used, only one bump stop per shock is
permitted."
"i. Ground Clearance: Minimum is 2.75 inches measured at the frame on the front and rear axle lines without driver, as raced."

In Formula Enterprises, GCR 9.1.1.I.2.H.b, change as follows:
"Front Springs: 600 lbs. ±25 lbs. Faulkner Part # WM203008 or Hypercoil Part # WM203011
Rear Springs: 1000 lbs. ±25 lbs. Faulkner Part # WM203009 or Hypercoil Part # WM203012 or
Front Springs: 800 lbs. ±25 lbs. Hypercoil Part # WM203013, Silver
Rear Springs: 900 lbs. ±25 lbs. Hypercoil Part # WM203014, Silver
Effective November 1, 2020, Part # WM203013 Front and Part # WM203014 Rear will be requiredfor FE2 and optional for FE."

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 FE, GCR section 9.1.1.I.2.F.e, add language as follows:
"Radiator screens are allowed and recommended. Screens may be placed no more than ¼ inch from the vertical plane of the
front of the sidepods."

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 FE, GCR section 9.1.1.I.2.M, make changes as follows:
"WET
Hoosier
Front: P/N: 44195 W3, 22.0 X 7.5-13 (compliant through 12/31/2022)
or P/N: 44196 W3, 22.0 X 8.0-13
Rear: P/N: 44217 W3, 22.0 X 9.0-13
a. A competitor shall start the race on at least 3 tires used in a qualifying session for the race as identified by markings made on
the tires by a race official. It is the responsibility of the competitor to ensure that his or her tires are appropriately marked prior
to (e.g. on the false grid), during, or immediately after (e.g. as the car leaves the track) a qualifying session.
b. For races with more than one qualifying session, a competitor shall start the race on any 3 or 4 marked tires from any
qualifying session for the race.
c. If a competitor chooses to start the race on any more than one tires that was not used in a qualifying session for the race and
not appropriately marked, the competitor shall forfeit his or her grid position and start from the back of the grid. This forfeiture
of grid position shall not apply if all qualifying sessions for the race were run under rain or wet conditions.
Table 2 (Spec Line Cars)
Car Engine
Wheel
Width (in)
± .060
Aero Transmission Weight Notes
Ralt RT40, Ralt
RT41, Swift 008, and
Swift 014 chassis

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

RM 21-04. In FE, GCR section 9.1.1.I.2.F.e, change as follows:
"Radiator screens are allowed and recommended. Screens may be placed no not protrude more than ¼ inch from in front
of the outside vertical plane of the front of the sidepods."

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 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 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 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 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 FE, GCR section 9.1.1.I.2.M, change as follows:
"Tires must be run as delivered in sets of 4 as stated below:"

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

In FE, GCR section 9.1.1.I.2.K.c, change as follows:
"Master cylinders must be the Girling type:
Girling F front master cylinder is .700" piston diameter, Part # WM802005
Girling R rear master cylinder is .750" piston diameter, Part # WM802006"

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 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 FE, GCR section 9.1.1.I.2.G.a.17, change as follows:
"A heat shield and heat insulation material may be used between the engine block and the exhaust system and is recommended
for the purpose of protecting hoses, shifter cable, and wiring from the heat of the engine and exhaust. Heat insulation material
may also be used to protect the fuel cell, fuel filter, fuel rail, and fuel lines."

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 FE, GCR section 9.1.1.I.2.K, add the following:
"f. Driver adjustable manual brake bias is allowed."

In FE, GCR section 9.1.1.I.2.F.g, change as follows:
"The front wing main plane, front wing secondary elements, front wing support mounts, and front wing endplates assembly and
its related mounting components must be used and mounted as delivered from Enterprises. Any m Modifications to these parts,
except as specifically noted herein, is strictly forbidden are prohibited. The front main wing plane angle is zeroed on the rear
upper aft transmission surface measured with a suitable angle gauge, i.e.: digital level on the top main plane 2 inches outward
from the nose box mounts element may be adjusted +2.5 to -0.5 degrees. It must meet a minimum measurement of negative .5
degrees (angled down in the back) and a maximum measurement of positive 2.5 degrees (angled up in the back). It is acceptable
to shim the main plane to obtain this measurement. Shimming 2 of the 4 verticals through the main element mounting points to
achieve adjustment range is allowed. The main element angle is measured relative to the reference plane. The main element is
checked on the upper surface, midway between the vertical mounting and outer secondary elements on both sides. Note: The
reference plane is the machined surface where the shock clevises are attached to the transmission case. Secondary wing
elements may be used in any of the provided adjustment holes. Gurney flaps (0.500" +/- 0.030") are permitted allowed as an
option for installation on the trailing edge upper surface of the front wing on secondary elements only, not the wing main
plane. They Gurney flaps must be securely attached in a secure fashion, without modification to the wing element except for
mounting hardware. Only .500” +/- .030” flaps are allowed. Maximum number of mounting locations on front flaps is 2 on each
flap and maximum hardware size is with two #8 (.156) hardware or tape. Gurney flaps, where attached, shall be are bent or
formed 90 degrees to have a sharp inner radiusand parallel to the upper surface of the wing element and. no t Tapered or "saw-
toothed" Gurneys flaps are not permitted. Gurney flaps are measured for total height as mounted from the upper surface of the
element."
In FE, GCR section 9.1.1.I.2.F.h, change as follows:
"The rear wing assembly and its related mounting components are to must be used and mounted as delivered. Any
m Modifications, except as specifically notedherei n, are strictly prohibited. The lower plane angle, zeroed on the rear upper aft
transmission surface, measured with a suitable angle gauge. i.e.; digital level on the top surface of the lower rear wing must
meet a minimum of –3.0 degrees (angled down in the back) and a maximum of +2.0 degrees (angled up in the back). It is
acceptable to adjust the lower rear element to meet these requirements element may be adjusted +2.0 to -3.0
degrees. Chamfering the upper inner corners of the wing mounting brackets to achieve the adjustment range is allowed. The
element angle is measured relative to the reference plane. The element is checked on the top surface, near the center, without a
Gurney flap. Note: The reference plane is the machined surface where the shock clevises are attached to the transmission
case. The upper rear wing element may only be adjusted within the parameter profile of the wing endplates and wing adjusters
as provided from Enterprises using any of the provided adjustment holes. No additional holes may be added. Gurney
flaps (0.250" +/- 0.030") are permitted allowed as an optionfor installation on the trailing edge upper surface of the on one or
both wing elements. They Gurney flaps must be securely attached in a secure fashion, without modification to the wing element
except for mounting hardware. Only .250” +/- .030” flaps are allowed on one or both elements with five #8 hardware or
tape.The Gurney flaps only, may extend beyond the parameters of the end plate are bent or formed 90 degrees to have a sharp
inner radius. Maximum number of mounting locations is 5 and maximum hardware size is #8 (.156). Gurney flaps, where degrees
and parallel to the upper surface of the wing element and no t Tapered or "saw-toothed"
Gurneys flaps are not permitted. Gurney flaps are measured for total height as mounted from the upper surface of the element."