Mini Stock Rules

Mini Stock Division

Mini Stock Division

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Eligible Models
Four cylinder compact cars
a. Foreign or Domestic
b. Stock wheelbase less than 104"
c. No four wheel steering cars
d. No four wheel drive cars
e. No convertibles
f. Mechanical fuel injection allowed if stock for that model
g. Fuel injection may be allowed on models not offered with carburetion. The 141 Speedway Officials will determine eligibility on a case by case basis.

Chassis
Frame
a. Must be stock for the make and model as produced and sold by the manufacturer
b. No modifications or alterations of any kind
c. Frame ties are optional
d. Vehicle must maintain a minimum of 4" ground clearance
    1. All measurements will be taken with the driver in the vehicle
    2. Exhaust must be at least 3" off the ground
    3. A small section of the floor may be boxed to raise the muffler

Suspension
Springs
a. Stock appearing steel spring that fits in original mounts in original location.
    1. Aftermarket springs allowed minimum 5" in diameter
        a. Front wheel drives may use an aftermarket 2.5" diameter spring on the front only
b. Springs may be altered (cut, heated, or bent)
c. No twist-in spring spacers allowed.
d. Lowering blocks allowed on leaf spring cars.
e. 2 weight jacks are allowed, front or rear, but NOT both
f. Spring spacers allowed
Shocks
a. Any OEM type shock allowed.
    1. No adjustable shocks allowed period!
b. Must be in stock location on stock mounts.

Spindles & Hubs
a. All components must be stock OEM.
b. No drop spindles.
c. Spindles stock for that make of car
d. No lightening of hubs.
Steering
a. Cars using aftermarket steering shaft must...
    1. Install a safety sleeve in the main shaft OR
    2. Use a complete aftermarket collapsible racing column
    3. An impact collar must be welded on the shaft before the final mounting bearing.
b. Stock tie rods only
Modifications
a. Upper A-frames or bushings may be altered for camber
b. Upper strut mount may be altered for camber
    1. Strut mount may be raised
c. Lower A-frames or strut mounts must remain unmodified
Track Width
Maximum front track width 61.5"
OEM Stock Sway Bars Only
a. Must be mounted to frame in stock position in stock mounts
b. End links may be adjustable

Roll Cage
a. 6 point roll cage is mandatory
    1. No offset cages
b. Minimum 4 drivers side door bars.
    1. Drivers side door bars must be plated with minimum 1/8" plate steel
    2. Door bars must have 2 uprights between each door bar.
    3. Drivers door bars should be flush with inside of door panel.
c. Cage must have 1 bar side to side at dash level
d. Minimum 2 right side door bars.
    1. Which may run straight between front and rear uprights.
e. Minimum 2 side to side bars behind drivers seat
    1. 1 bar side to side at shoulder height
    2. 1 bar diagonally from top to bottom
f. Each side of cage must have an upright bar at vent window area (Wing Window Bars)
g. Cage must be securely mounted to unibody
    1. 1/8" x 4" steel plates welded or sandwich bolted to the floor OR
    2. Bottom door bars on each side stitch welded to rocker panels
h. Mandatory bars will be 1 3/4" x 0.095 round steel tube
i. Driver foot protection bar highly recommended
j. 2 bars from top of rear hoop extending through to the trunk area and mounted securely to trunk floor
k. Bars from firewall forward optional
    1. But may not be connected to front bumper
l. All 90 degree connections must be gusseted
m. All roll cages, installations and welding will have to meet approval of safety inspectors
n. A 1/8" steel plate must be welded to left side floorboard area from firewall to behind seat mounts
o. While sitting in seat, mandatory 3" clearance between top of driver's helmet and top of roll cage

Bodies
Body must be complete.
a. Double wall panels may be trimmed
b. Aftermarket or neatly fabricated nose may be used (officials discretion)
c. Doors may be gutted for installation of door bars.
d. Doors must be welded shut
    1. Door skins may be fabricated of comparable thickness steel
e. Floor pan must be complete with any holes sealed
f. Trunk floor may be trimmed out for installation of fuel cell only.
g. All interior upholstery and flammable material must be removed.
h. All exterior chrome, door handles, etc. must be removed
i. All glass, except windshield, must be removed
    1. If using lexan or screen for windshield, must be braced with either (2) 1" x 1/8" straps, or (3) 3/8" minimum square or round steel tubing, evenly spaced.
    2. Mesh must be 1" or smaller, 0.035 minimum wire diameter type 304 stainless steel or equivalent
    3. Drivers using screens must use approved full face helmet
    4. No tinted windows
k. Front and rear firewalls must be completely sealed with minimum 20 gauge steel
    1. If car is a hatchback, a 20 gauge compartment must separate driver from fuel cell (in addition to fuel cell can)
Hood & Trunk
a. Remove stock latches
b. Hood and deck lid pins mandatory
c. Hood must be sealed tightly at firewall or dash
d. Hood scoops are allowed
e. Cold air induction is allowed
f. Spoiler may be stock or fabricated if less than 5".
Bumpers & Protection Bars
a. Stock type steel or aluminum bumpers
    1. Cars with rubber noses may use round tubing bumpers
    2. Maximum 1 3/4" diameter
    3. Non factory bumpers must have a collapsible section built in (such as shear pins)
b. No reinforcing - factory energy absorbing shocks must remain functional, not welded tight
c. Bumper brackets may be welded or bolted to frame horns
d. Bumpers must be capped to fenders to prevent hooking another car
e. Must have front and rear tow hooks, chain loop or cable OK
f. Radiator protection bar behind grille between frame rails only
g. No cowcatchers or brush bars
h. Side rub rails maximum 1" square tube
    1. Must have 45 degree capped ends
    2. Must be securely mounted no further than 1" from the end of the rub rail
    3. Competition Committee members will closely inspect rub rail mounting

Numbers
a. Contrasting Colors
b. Height:
    1. Doors: Minimum 16" high
    2. Roof: Minimum 24" high
    3. Letter suffixes must be at least 50% of Number size
c. Width: Minimum 3"
d. Clearly readable from the scoring tower from any point on the racing surface
e. Front and rear bumper numbers must be a minimum of 5" high
f. No "spray can" numbering
General Appearance
a. All cars must be neat appearing
    1. Cars must be painted
    2. No loose body panels
    3. No dented up cars
    4. Damage should be repaired weekly
    5. No profane or otherwise offensive slogans
    6. Rust should be repaired
b. Cars not meeting appearance standards will not be allowed to compete.

Drivers Compartment
Kill switch
a. must be "push-pull' or metal toggle type
b. Must be clearly labeled
c. Must be easily accessible from either side of car
d. Must be reachable by driver when strapped in
Fire Extinguisher
a. Must be fully charged
b. Must be securely mounted within reach of driver
c. Must be quick release mounting
Padding in Drivers Area
a. Center of steering wheel must be padded
b. Roll bar must be padded by drivers head
c. Inside of drivers door must be padded
d. Additional padding required in areas of possible contact
Window Net
a. Net must be permanently mounted on bottom
b. Quick release mechanism must be toward front roll cage upright near roof
Seat
a. Must be aluminum only
b. Must be properly installed
c. Must be high back design
    1. Headrest must be supported
    2. Rib rest must remain flexible
d. Must be mounted with minimum 3/8" hardware
    1. Must use oversize washers
    2. Minimum 6 mounting points
        A. 4 points on seat bottom
        B. 2 points on seat back
Five (5) point racing harness
1. Condition of belts is up to the Officials discretion
2. 3" lap, 3" shoulder, and submarine belt required
3. Secured with minimum 3/8", grade 5 hardware
    A. Lap mountings must swivel
    B. Shoulder belts must be supported at shoulder level
Oil Pressure Lines
a. No plastic
b. Metal only
Mirrors
a. Are allowed

Engines
Definition
"Unmodified" - Sanding, grinding, porting, polishing, relieving, acid dipping, chemical treating, abrasive blasting, redrilling, addition of material, flow enhancing techniques, etc. are all considered to be modifications and therefore not legal in any further areas marked "No modifications".
Must Be Stock for Make and Model
a. Must be stock in location up and down, front and back, and side to side
b. No rotary engines
c. No dual overhead cam engines Holley 5200 or Weber 32/36 may be substituted on any car.
d. No more than 2 valves per cylinder
e. Aluminum blocks will be assessed a weight penalty
Maximum 0.060" Cleanup Overbore
a. Pistons must be stock or stock OEM replacements
    1. No changes in piston compression ratio allowed
    2. No lightweight forgings
Stock Crankshaft Only
a. No aftermarket cranks
b. No stroker cranks
    1. Ford 2300: Max stroke is 3.126"
        A. Offset crank grinding prohibited
        B. Ford 2500 crank is NOT allowed
c. No lightweight or lightening of crankshafts allowed
OEM Style Connecting Rods Only
a. No lightweight rods of any kind
b. Stock length rods only
    1. Ford 2300: 5.205" rods ONLY
c. Stock for that engine only
d. Connecting rods may be polished for stress relief
Maximum Cam Lift
a. measured at valve 0.510" at valve
b. No roller cams
c. Ford 2300 cannot have solid lifters due to rule V.G.6.a
d. Adjustable cam timing OK
Manifold and Carburetor
a. Must be stock 2 bbl manifold and stock carburetor for make and model
b. No modifications allowed
    1. No carburetor that flows over 280 CFM allowed.
c. Holley 5200 or Weber 32/36 may be substituted on any car
d. 1" maximum spacer or adapter plate over stock configuration
    1. All cars must use an approved 2 hole plate under carburetor
e. No Holley 350s or 500s allowed
f. Fuel injection may be allowed on vehicles that cannot be easily or competitively outfitted with a Carb
    1. Call for eligibility and special requirements
g. 2 throttle springs mandatory
h. GM intake manifolds must be stock or pre-approved
i. EGR plate may be removed
Cylinder Head
a. Stock for make and model with no performance advantage
b. No SVO cylinder heads allowed
c. No multi valve heads
d. Stock valve size (diameter) only
    1. No Chevy Valves in Ford Heads
e. Valve spring pockets may be modified for larger springs
f. Shaving head is allowed
    1. No other modifications allowed
Exhaust Header
a. Exhaust headers are allowed
b. Exhaust must end behind driver
c. Muffler is mandatory
d. 95 decibels maximum
    1. Measurement will be taken from pit grandstand
    2. One week to fix
    3. $20 fine every week not fixed
e. No exhaust pipe in drivers compartment
    1. Exhaust header may not pass through stock firewall or floor pan
Engine Location
a. Engine must be in stock location for make and model

Transmission & Drivetrain
Transmission
a. Must be stock for make and model
a. Transmission must remain completely unaltered
b. All gears must function

Clutch, pressure plate, and flywheel
a. must be stock for make
b. No aluminum flywheels
c. No aftermarket performance units allowed
    1. No aluminum allowed in any part of clutch
    2. Clutch discs must be round fullface, no puck style discs allowed
d. No aftermarket or excessively modified flywheels.
    1. No machining allowed anywhere besides clutch face area.
    2. All original casting and part numbers must be intact and unaltered.
    3. Flywheels must be within 3.5 lbs. of original weight.
    4. No holes allowed under ring gear.
    5. Ford flywheels must be at least 1" thick
e. Scatter shield or explosive blanket required
    1. 14 gauge steel plating covering the top 180 degrees of bell housing is adequate
Clutch/Flywheel Inspection Hole
a. All cars are required to have a clutch/flywheel inspection hole
b. If dust cover or clutch release fork hole is in appropriate position to view them, it will be adequate
c. 1" hole is preferred
d. If inspection is not convenient, disassembly will be required
e. Track may ask for disassembly of a transmission/clutch/ flywheel at any time

Differentials & Driveshafts
Rear End
a. must be stock for make and model
b. May be locked with a spool or mini spool
c. Stock type limited slip allowed
1. No Detroit locker or other ratcheting types allowed
2. No inserts: EZLock, LockRite, Powertrack, Gearless Locker
Driveshaft Color
a. must be white or bright
Driveshaft Composition
a. No aluminum driveshaft
b. No composite driveshaft
Rear Wheel Drive (RWD) Cars
a. All RWD cars must have driveshaft safety hoop of minimum 1" x 1/8" strap steel
b. Hoop should be 6" behind front U-joint

Cooling System
Radiator Eligibility
a. Any radiator may be used
b. Must fit between uncut frame rails
c. Hood must close
Coolant Requirements
a. Water Only
b. Anti-freeze is $20.00 fine
Fan Shroud
a. Top 180 degrees of fan must be shrouded with minimum 18 gauge steel
b. Factory stock shrouding acceptable if it covers top of fan
Electric Fan
a. Electric fanss must operate by a clearly labeled switch
b. No automatically controlled fans
Overflow Catch
a. Required: 1 quart (minimum) overflow catch can

Brakes
a. All cars must have safe functioning brakes at all four wheels
b. Stock master cylinder only, must remain in stock location
c. No made for racing components
d. NO Four wheel discs allowed unless they were original equipment on that model

Wheels & Tires
a. Maximum 6" wide rims
b. No aluminum or mag wheels
c. Aftermarket or approved reinforced rim on right front
d. Minimum backspace 2"
e. 1" lug nuts required
f. Track tire is Hoosier 790
1. 13" or 14" only
g. No Tire softening or chemical treatment of any kind allowed
1. Track reserves the right to impound any tire for whatever length of time necessary to determine if it has been chemically treated.
Wheel Spacers
a. A maximum (1) wheel spacer is allowed per wheel.
b. Must be at least 6" in diameter.
c. Must be 1/4" thick +/- 1/16"

Electrical
a. One 12 volt battery only
1. Securely mounted in a battery box away from fuel cell and lines
b. Stock ignitions only
1. Stock for make and model

Fuel & Tanks
Fuel Cell
a. A fuel cell recommended
    1. If fuel cell is used, trunk may be trimmed out for installation
    2. Minimum 10" ground clearance
    3. Must have fuel cell protector bar angle braced to frame
    4. Cell must be in a minimum 20 gauge can
    5. Must be secured by four 1/8" x 1" straps
    6. Maximum 12 gallon capacity
Farm or Marine Tank
a. Maximum 6 gallons
b. Trunk floor must be fully intact and trunk sealed
c. Must be in 20 gauge can
d. Mounting will be heavily scrutinized, inspectors decision is final
Fuel Lines
a. No fuel lines through drivers compartment, unless through continuous conduit
b. All vent lines must have check valves
Fuel Tanks
a. No bottom draw fuel tanks
Fuel Types
a. No alcohol
b. No oxygenators or nitro additives
c. Fuel must be automotive gasoline only
d. Track reserves the right sample fuel to determine legality
Fuel Pumps
a. Stock fuel pumps
b. Electric fuel pump allowed if stock for make and model only
    1. Must have manual shutoff and be clearly marked

Weight
a. A minimum weight is 1400 lbs. + [(0.5 x engine displacement I n cubic centimeters)]
b. 2600 lb. Maximum required weight of any car
c. Fuel injection: Track discretion on a Case by Case basis
d. Weighing includes driver in drivers seat
e. All ballast must be painted white and have car number on it
f. All weights must be bolted; (1/2" diameter minimum hardware) or welded to frame
g. Loss of weight; immediate disqualification and $20.00 fine
h. Due to significant differences in chassis design and drivetrain configurations, on a case by case basis, any model may be subject to special weight requirements in an effort to equalize the competition
i. Maximum 60% left side weight
j. Tech Inspectors may, at their discretion, add weight penalites for infractions

Teardown and Penalties
Track Teardown
a. The 141 Speedway will teardown engines on a regular basis.
1. Top End teardown - $40 awarded if legal
2. Bottom End teardown - $125 awarded if legal
b. Any car subject to teardown that leaves the grounds or refuses the teardown will be suspended for 4 weeks.
c. The track retains the right to tear down any engine at any time without compensation.
Competitor Teardown
A driver competing in the same feature event may request a teardown of another competitor.
Requirement of Challenger
a. Request Must Be in Writing
b. Drivers making the request must have finished on the lead lap
c. Protestor's own car must pass inspection
Time Requirement
Requests for a competitor teardown must be made within 10 minutes of the end of the event.
Amount of Protest Money
a. $200.00 to do a Top End Check
b. $500.00 to do a Bottom End Check
Teardown Findings
a. If found to be legal, protestee receives the protest money
b. If found illegal, the protester receives the protest money; illegal car earns no points or money for that evening as well as possible long term suspension
Refusal to Teardown
Any car subject to teardown or that has been notified of a protest, that leaves the grounds or refuses the teardown will be suspended for 4 weeks
Infractions and Penalties
a. Depending on the severity of the infraction, the track may issue a penalty up to loss of all accumulated points, surrender of pay, and/or suspension up to a year. Refer to the Section 5 - Penalties

Safety Requirements
Competitors must meet the following safety requirements in order to participate in an event
a. Driver's suit made of a flame retardant nature. The condition of the suit is subject to the officials' discretion.
b. A minimum Snell 2000 rated or newer helmet. SA rated helmets recommended. M rated helmets allowed if used in conjunction with fire retardant head sock.
c. Eye protection is required.
d. Fire retardant gloves are required
e. Fire retardant neck brace is required. A Hans or other style head and neck support system may be used in place of a brace

Restrictions
a. No two way radios allowed in cars
b. No traction control
c. No turbos, superchargers, or nitrous oxide
d. No Titanium allowed anywhere