Add
the following language to GCR section
17.1.9:
SPEC
MIATA (SM)
17.1.9.
Spec Miata Class (SM) (Regional Class Only): These specifications are part of
the SCCA General Competition
Rules (GCR) and all auto-mobiles shall conform to GCR Section 17.,
Automobiles.
A.
PURPOSE AND INTENT
The
Spec Miata (SM) class is intended to provide the membership with the opportunity
to compete in low cost cars with limited modifications, suitable for racing
competition. It is the intent of the Competition Board that the philosophy of
this class be similar to the Improved Touring classes, it shall always remain a
regional only class to encourage low cost, entry level, production car based
competition.
Further,
the rules are intentionally designed to be more conservative than the Improved
Touring class, but with equivalent safety standards. The Spec Miata class will
be reviewed on a yearly basis for participation. If the class participation
drops below a reasonable level, the cars will be assimilated into the
appropriate Improved Touring class.
These
rules are intended to SUPPLEMENT those of the Showroom Stock Category
Specification (SSCS). The Spec Miata class shall strictly follow the SSCS except
for the modifications permitted by these rules. Unless specifically mentioned
or approved in these rules, no additional modifications may be made.
B.
CLASSIFIED CARS AND WEIGHTS
1990
- 1993 Mazda Miata 1600cc at 2275 pounds
1994
- 1997 Mazda Miata 1800cc at 2430 pounds
Cars
are to be weighed with the driver.
C.
AUTHORIZED MODIFICATIONS
The
following items represent the only modifications and safety items permitted
and/or required on Spec Miata automobiles beyond those of the SSCS. No permitted
component/modification shall additionally perform a prohibited function.
1.
Engine Modifications
a.
Induction System
1.
All air entering the intake tract shall pass through the fuel injection
air inlet.
2.
1600cc cars may replace the stock air box with a cone style air filter
assembly. The air filter element is unrestricted. 1800cc
cars must use the stock air box, but the air filter element is
unrestricted.
3.
1800cc cars shall use a restrictor in the fuel injection system. The
throttle restrictor shall be placed between the throttle body and plenum
and shall be a 0.060" flat steel or Aluminum plate with the specified
orifice. No
air shall bypass the throttle restrictor.
1994
- 1995 47mm restrictor
1996
- 1997 45mm restrictor
b.
Fuel System
1.
Unleaded fuel filler trap door and
c.
Ignition/Electrical System
1.
Ignition wires may be substituted.
2.
Ignition timing is unrestricted.
3.
Batteries may be replaced with those of an alternate manufacturer,
provided they are of similar amp-hour capacity, size, and weight and are
fitted in the standard location. Additional battery hold-down devices may
be used, and are strongly recommended.
d.
Exhaust System
1.
The factory exhaust system beyond the OEM front down pipe may be replaced,
provided:
a.
Said replacement system retains the original configuration, e.g. single
tube design, and the tubing diameter is a maximum of 2.25".
b.
The system shall exit behind the rear subframe.
c.
No expansion chambers.
d.
The system meets all event specific sound requirements (see GCR Section
15).
e.
Clutch System
1.
Any clutch disc and pressure plate of stock diameter may be used, provided
that they shall be bolted directly to an unmodified stock fly-wheel. The
addition of an external scattershield per GCR 17.24., is permitted and
recommended.
2.
Cooling System
a.
Any radiator may be used, provided it is mounted in the original location,
maintains the same plane as the
b.
Thermostats may be modified, removed, or replaced.
3.
Transmission/Final Drive
a.
Transmission and final drive ratios must remain stock for the year of car.
b.
1990 to 1993 Miatas may use the stock, unmodified viscous limited slip
differential or the MAZDASPEED Motorsports Development limited slip
differential, part number #QN10-64-A00 (previously TOY1-27-200 &
0000-02-5501).
c.
1994 to 1997 Miatas may only use the stock Torsen limited slip differential.
4.
Chassis
Chassis
modifications are limited to the addition of the MAZDASPEED Motorsports
Development "Spec Miata kit" and those modifications detailed in
this area.
a.
MAZDASPEED Motorsports Development Spec Miata kit
1990-93
1.6 DOHC K-SPEC-M5-SUSP
1994-97
1.8 DOHC K-SPEC-M5-SUS8
The
following is a breakdown of components supplied within these kits. All parts
numbers are MAZDASPEED Motorsports Development parts numbers. No
substitution of parts is allowed. The kits must be used in their entirety.
1.
Shocks
Front
Bilstein 0000-04-5225-BL
Rear
Bilstein 0000-04-5226-BL
2.
Springs
Front
Eibach ERS 700 lbs/6" 0000-04-9700-06
Rear
Eibach ERS 325 lbs/7" 0000-04-9325-07
3.
Coil-Over kit Front/Rear 0000-04-5402AW
4.
Anti-Roll Bars
K-SPEC-M5-SUSP
Eibach
kit - front / rear bars 0000-04-5302-EB
Front
24mm Adjustable
Rear
15mm Adjustable
K-SPEC-M5-SUS8
Eibach
kit - front / rear bars 0000-04-5303-EB
Front
27mm non-Adjustable
Rear
15mm Adjustable
b.
Cars registered prior to 1/1/2003 may weld a 63.5 mm centering ring to the
shock top mount and turn the stock length bump stop (Part# NAO1-28-111) to
an outside diameter of 58mm.
c.
Subframe braces may be updated to stock 1997 configuration utilizing the
MAZDASPEED Motorsports Development Spec Miata kit.
d.
Anti-roll bar links may be replaced, but the attachment points must remain
stock. The control arms and specified anti-roll bar may not be modified.
e.
Cars may decamber wheels by the use of factory means to a maximum of two (2)
degrees negative in the front, and two and one half (2.5) degrees negative
in the rear.
f.
No other relocation or reinforcement of any suspension component or mounting
point is permitted.
g.
Hardware items (nuts & bolts) may be replaced by similar items
performing the same fastening function(s).
h.
Manual or power steering racks may be used. Power steering racks may be
converted to manual by removing all power steering components.
5.
Brakes
a.
Backing plates and dirt shields may be ventilated or removed.
b.
Brake lines may be replaced with steel lines or Teflon lined metal braided
hose. Cars with antilock braking systems must have the system disabled as
specified in GCR 11.2.1.E.
c.
Parking brakes, mechanisms, and actuating components may be removed.
6.
Wheels/Tires
a.
Any wheel/tire may be used with-in the following limitations:
1.
Maximum rim diameter is fifteen (15) inches. Maximum rim width is seven (7)
inches.
2.
Knockoff/quick change type wheels are prohibited. Wheels must be made of
metal.
3.
Any DOT-approved tire is permitted. Racing, recapped, or regrooved tires are
not allowed. Tire size is unrestricted. The only modifications allowed to
tires are having treads "shaved" or "trued." Individual
regions may require spec tires. Supplemental regulations for specific events
should be checked.
4.
Track may be changed to accommodate larger tires, provided that there is
safe tire/fender/chassis clearance under all conditions of steer, bump, and
rebound. Wheel spacers are permitted.
5.
Tire tread (that portion of the tire that contacts the ground under static
conditions) shall not protrude beyond the fender opening when viewed from
the top perpendicular to the ground. To determine compliance, the vehicle
should be rolled through a powdered substance, as raced with driver, in
order to indicate the tire tread contact patch under static conditions.
7.
Body/Structure
a.
Fenders and wheel openings shall remain unmodified. It is permitted to roll
under or flatten any interior lip on the wheel opening for tire clearance.
Non-metallic inner fender liners may be removed.
b.
The "R" package Miata chin spoiler is allowed provided it is
mounted in the location intended by the factory.
c.
Minimum ride height is unrestricted, but no part of the car, except for the
exhaust system and suspension components, shall be lower than the lowest
part of the wheel rims.
d.
Windshield clips per the GCR Section 17.33. are permitted and recommended.
e.
Convertible tops and attaching hardware shall be completely removed. Cars
may compete with the Mazda factory detachable hard top in place (latches
shall be replaced with positive fasteners), but it is not mandatory. When no
top is used, driver shall wear arm restraints, and the cage will meet the
helmet clearance rule. See GCR 18.3.1. for additional information.
f.
Body side moldings, rocker panel moldings, and wheel opening trim pieces may
be removed.
g.
Hood inner plastic liner may be removed.
h.
Hood clips are permitted. Stock hood latches may be disabled or removed.
i.
Ducting may be added to provide fresh air to the driver compartment. This
ducting shall be located in the driver and/or passenger vent window area by
a means of a transparent/alternate vent window material and duct with no
modifications to the bodywork.
8.
Driver/Passenger Compartment –Trunk
a.
Any steering wheel except wood rimmed types may be used. Any shift knob may
be used.
b.
Gauges and instruments may be added, replaced, or removed. They may be
installed in the original instrument(s) location using a mounting plate(s),
or any other location using a secure method of attachment. Other than
modifications made to mount instruments and provide for roll cage
installation, the remainder of the dash "board" or panel shall
remain intact.
c.
Any interior or exterior mirrors may be used.
d.
Front passenger seat, sun visors, seat belts and their attaching hardware
and bracketry may be removed.
e.
Carpets, center consoles, cargo bins, drivers seat belt, floor mat, radio
system, headliners, dome lights, grab handles and their insulating and
attaching materials may be removed. Other than to provide for the
installation of required safety equipment or other authorized modifications,
no other driver/passenger compartment alterations or gutting are permitted.
The driver's door window glass, window operating mechanism, and inside door
latch/lock operating mechanism may be removed and the inner door structural
panel may be modified, but not removed. The stock side impact beam, if
equipped, and the outside door latch/lock operating mechanism shall not be
removed or modified. This gutting of the door shall only be made to the
driver's door and shall only be made if roll cage incorporates NASCAR-style
side protection extending into the door.
f.
Any removable covers used to cover spare tires, tools, bins, etc., may be
removed along with attaching hardware and bracketry. Carpets, mats, and
their insulating or attaching materials may be removed from the floor and
recesses of the cargo/ trunk/spare tire area.
g.
Dead pedal/foot rest and heel stop may be added.
h.
Ballast up to 100lb maximum may be located in the front passenger footwell
area, aft of the firewall and any footwell angle, and forward of the
passenger seat. Installation shall be per SSCS.
9.
Safety
a.
Roll cages shall meet all requirements of GCR Section 18., requirements for
Showroom Stock cage configuration,
tubing size, and material.
1.
Regardless of car weight, all Spec Miata autos may be constructed to the
requirements for a 2095-pound car.
b.
Steering lock mechanisms shall be removed.
c.
An electrical master ("kill") switch is required. See GCR Section
17.27., for requirements.
All Spec Miata Competitors are encouraged
to join Mazda’s Team Support Program. The program enables competitors to
purchase Mazda stock and competition parts at discount prices. Call
800-435-2508, e-mail to comppart@mazdausa.com,
or Fax 949-727-6943 to request an application and further details. |
