FOUR-CYLINDER MINI STOCK RULES
(Formerly the Bomber Class)
This class is intended to be an entry level class. It is primarily for new or less experienced racers to get into our sport while having fun and gaining experience before moving up to a faster class. Please remember that these rules are to allow building and racing a safe and fun but inexpensive car. If you feel the need to modify your car or to go faster than these rules allow, please move up to a different class. Think cheap and fun!
DESCRIPTION OF CAR
Any stock four-cylinder, four or more passenger car or regular or extended-cab truck allowed. No twin carb, turbo, 4x4 or rotary engine vehicles allowed. Cars must be 10 years or older. Vehicles to remain stock-appearing. No alterations or modifications will be allowed unless specifically mentioned in the following rules.
BODY
b1. All flammable materials, chrome trim,
pot metal and glass to be removed.
b2. Firewall to remain stock and have all
holes covered or filled.
b3. No body panels may be removed except
for driver's door panel. This may be removed for door bar installation.
Driver's "B" pillar may be removed to allow easier exit
kkkifrom
car.
b4. Fenders may not be radiused.
b5. All body panels must be stock. Minimum
50% original material. Bumpers must remain stock with no reinforcing.
b6. Missing body panels must be replaced
by the next race weekend.
b7. Bumpers must be strapped to metal body
or frame with securely attached minimum 1/8" thick 2" wide steel.
b8. Doors must be welded or bolted shut.
b9. Stock latching of hood and trunk lid
must be removed and replaced with hood pins (reinforced with minimum
2" diameter washers).
10. One door mirror allowed (not to protrude past door). One rearview
mirror allowed inside car.
11. All cars must have either a factory glass or Lexan windshield or
a screen in front of the driver. No Plexi-glass allowed. Must have a
vertical bar in centre of windshield to kkkideflect
hood upwards in case of accident. Must be min 1/8" thick 1" wide steel.
Two bars required if using stock windshield. If factory glass windshield
or screen used,
kkkidriver
imust
wear either approved eye protection or a helmet with full face shield.
12. Quarter windows of tin or Lexan allowed for sponsors. No other windows
allowed except on trucks which must use a rear window. This is to isolate
the fuel tank area from kkkithe
driver's compartment.
13. May use single bucket seat or racing seat. Must be securely attached
to the roll cage from the lower left door bar to a bar in the center
of the vehicle.
14. Driver's door may have top 4 inches (maximum) folded in to allow
easier entry and exit. Top door bar must be at top of door openingbif
door is modified.
15. Must have four tow chains (one per corner of car).
16. Seatbelts must be attached with maximum size bolt that fits seatbelt
mounts without modifying seatbelt mounts. Grade 8 or better.
17. No brazing allowed on car-parts must be bolted or welded only.
18. No plastic fire extinguisher mounts.
19. Optional spoiler on front bumper, not to protrude past widest point
of fender.
20. Rub rails optional. Rub rails with a maximum size of 1" x 1" 1/8"
square tubing may be installed at the widest point of the body, touching
the body during its entire
kkkilength,
wheel well to wheel well. It must be painted the same colour as the
background it touches and be as inconspicuous as possible. Mounted with
minimum
kkki3
3/8" carriage bolts, with one bolt in centre of bar and one at each
end. Ends must be cut and capped at 45° angle (to prevent hooking of
other cars).
ROLL
CAGE
b1. Four-point roll cage only mandatory.
Cage may not be attached to the car in more than four places (i.e. door
bars may not be welded to body).
b2. Cage must be minimum 1 15/32" OD, .095
wall steel pipe. No exhaust pipe or galvanized pipe allowed.
b3. No front or rear hoops allowed. One
single bar allowed between front shock towers to keep towers from collapsing.
May not attach to either firewall or rad support.
b4. Must have minimum four door bars on
left side (extending into driver's door) and two door bars on the right
side. Top bar to be no more than 4" below top of door.
kkkiMust
have at least two rows of vertical bars between driver's door bars.
One vertical bar between passenger door bars.
b5. Posts to be welded securely to frame
or to minimum 4" square 3/16" steel plate fastened to floor with a minimum
of four ½" bolts. Must have steel plate under floor
kkkiwith
bolts going through top plate, floor and bottom plate.
b6. Bars that could come in contact with
driver must have approved padding on them.
b7. No nerf bars on outside of body.
b8. Roll cage must be passed by tech crew.
b9. Gusseting of cage recommended.
SUSPENSION
b1.
Absolutely no modifications allowed to suspension. Wheel alignment may
be adjusted within limits of stock parts with no modifications, except
as noted below.
b2.
On rear wheel drive cars: Camber on right front wheel may be adjusted
by stock vehicle adjustment procedure or by lengthening the control
arm bolts to add shims,
kkkire-drilling
or slotting mounting holes to adjust the mounting location of the strut
and/or control arm. No other
modifications may be done to allow adjustment.
b3.
On front wheel drive cars: The right front strut tower may be modified
for camber purposes only and may be braced to firewall or left front
strut tower.
b4.
Skid plate on RF lower control arm is recommended. Must be minimum 8"
long, 3" wide and ¼" thick with turned up ends. It must be mounted so
it will contact the
kkkitrack
before the rim or suspension.
b5.
May pre-load stock sway bar.
TIRES
AND WHEELS
b1. All cars must use either 13", 14",
or 15" wheels. No rim staggering allowed-all rims must be either 13",
14", or 15".
b2. All rims must be stock for that vehicle.
b3. No tires wider than P205/70 allowed
on carbureted vehicles and P195/70 on fuel-injected vehicles (i.e. tires
that would be allowed are: P195/70R14, P185/80R13).
kkkiBias
ply tires are NOT allowed-radial tires only.
b4. No tires without aspect ratio on sidewall
allowed (i.e. no 6.00-14" tires allowed). No studded tires allowed.
Stock, DOT approved street legal tires only. No recaps allowed.
b5. Cars with 13" tires can go down to
a 65 profile from a 70 profile. Only the 13" NOT 14".
BRAKES
b1.
Working four wheel hydraulic brakes mandatory. Brake checks will be
performed randomly throughout the season.
ENGINE
b1.
Stock four-cylinder engine only. Maximum 2.5L engine size. Engine must
be stock for that year and model of vehicle. No modifications to engine
allowed other than
kkkiremoval
of emissions equipment.
b2.
No twin carb, turbo or rotary engines allowed.
b3.
Air cleaner is mandatory but type is optional. Air cleaner must not
draw air from outside engine compartment.
b4.
Stock fuel injection allowed with no modifications whatsoever.
b5.
Dual cam, 16 valve engines will be restricted to 2.0L engine size.
b6.
In order to automatically shut off the electric fuel pump in case of
an accident, rollover, etc., all cars with EFI and with stockbelectric
fuel pumps (i.e. Honda Accord)
kkkimust
use a Ford inertia switch wired into the fuel pump circuit and mounted
to left of the steering column. See diagram below.
b7.
Maximum 94 octane pump gas only. No aviation or racing fuels allowed.
b8.
Engine mounts must be stock, but may have upper and lower sections welded,
bolted or chained together (to prevent mounts from breaking in the event
of a crash).
FUEL SYSTEM
b1.
a) On carbureted cars with mechanical fuel pumps: stock fuel tank must
be removed and replaced with an approved fuel cell or boat tank. The
tank must be mounted in
kkkikkkithe
trunk of the car as far forward as possible, preferably over the rear
axle. Plastic tanks or fuel cell must be encased in a metal box.
bbbb)
EFI and carbureted vehicles with stock electric pump must use stock
fuel tank with built-in electric pump, stock lines etc., and subject
to tech crew approval. Fuel
kkkikkklines
on cars with electric pumps must remain stock-no splicing in rubber
hose etc. Stock fuel tank must have a skid plate under it. Must be a
minimum ?" metal, the
kkkikkksame
size as the tank with sides open to allow spilled fuel to escape. Skid
plate must be attached with minimum ?" bolts and will be subject to
tech crew approval.
kkkikkkFuel
filler must be inside trunk compartment. Tank must be completely isolated
from the driver. In order to automatically shut of the electric fuel
pump in case
kkkikkkof
an accident, rollover, etc., all cars with EFI and with stock electric
fuel pumps must use a Ford inertia switch wired into the fuel pump circuit
and mounted to the
kkkikkkleft
of
the steering column.
b2.
Must have minimum 4" hole under tank to allow any spillage to escape.
b3.
Must have screw type cap.
b4.
Tank must be securely attached to car with steel strapping 1" by 1/16",
at tech crew's discretion.
b5.
Must have fuel tank vent pipe extending below bottom of tank and on
left side or an approved roll-over check valve.
b6.
Carbureted vehicles must have no more than 6 inches of rubber fuel line
in any one place allowed with a maximum of 18" of rubber fuel line in
the vehicle. Fuel lines
kkkion
vehicles with electric pumps must remain stock. No splicing in rubber
hose, etc.
bNote: The tech crew will not tolerate
improperly mounted fuel tanks. These rules are for everyone's safety.
EXHAUST
SYSTEM
b1. Stock size exhaust pipe only. Mufflers
optional.
b2. Exhaust must exit behind driver and
be pointed away from the fuel tank vent.
b3. Stock exhaust manifold only for that
model.
b4. Catalytic converter may be removed.
COOLING SYSTEM
b1.
Cooling system must be stock with no modifications other than removal
of thermostat.
b2.
Any OEM radiator allowed as long as it fits under the hood of the car
without excessive modifications.
b3.
No antifreeze allowed.
b4.
May use electric fan or stock fan and shroud. Vehicles without shrouds
may have a shroud added. All vehicles must have a shield to cover
the top of the fan.
b5.
Must have minimum ½ gal overflow container mounted in engine compartment.
TRANSMISSION
b1. Transmission must remain stock
for that model.
b2. Must have all working forward and reverse
gears.
b3. Must use stock flywheel, clutch, torque
converter, etc. for that model.
b4. Aftermarket transmission coolers allowed.
Rubber hoses to cooler must be double clamped and no longer than necessary.
b5. Must have scattershield such as conveyor
belting over top of the bellhousing to prevent a blown clutch from coming
into the driver's compartment.
REAR END
b1. Stock rear end only for that vehicle
model.
b2. No posi, welding of spider gears, etc.
allowed.
ELECTRICAL
SYSTEM
b1. Battery must be securely fastened
to car, preferably to the roll cage and completely isolated from the
driver.
b2. Battery must be in a metal box if not
mounted in interior of car. If mounted in interior, it must be either
in a plastic boat box or metal box and secured with steel
kkkihold-downs.
Battery must be covered and must have plastic or rubber over the terminals.
Installation must be passed by tech crew.
b3. Plastic 'boat' battery box may be used
to cover battery but battery must be secured to car with steel hold-downs.
b4. All switches must be clearly labelled
and be located where safety personnel and driver (while strapped in)
can easily reach them.
b5. Alternators must be used and working.
Items not specifically covered in the rules are to remain stock.
Any "grey areas" in the rules are to be referred to the tech crew. If
you have any doubts-ask the tech crew first!!
Any equipment that the tech crew considers exotic
or not in the intent of the rules will be considered illegal.
