05/18/2026
Notice: Please share for them.
I am not able to put in comments.
2026
BEMIDJI SPEEDWAY
FOUR CYLINDER MINI-STOCK RULES
The rules and regulations set forth herein are designed to provide orderly conduct of the racing events
and to establish acceptable requirements for such events. These shall govern the condition of all events,
any participating in these, all participants are deemed to have complied with these rules.
NO EXPRESSED OR IMPLIED WARRANTY OF SAFETY SHALL RESULT FROM PUBLICATION
OF OR COMPLIANCE WITH THESE RULES AND REGULATIONS. They are intended as a guide for
conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator or
official.
Bemidji Speedway shall be empowered to permit reasonable and appropriate deviation from any of the
specifications herein or impose any further restrictions that in their opinion do not alter the minimum
acceptable requirements. Any interpretation or deviations from these rules are left to the discretion of
Bemidji Speedway. THE DECISION IS FINAL.
Age limit for the Mini-Stock class is 14 years old, as determined by the insurance carrier.
Points will follow the Wissota points system, points will stay with the car unless the car is sold to another
person, this allows the use of a substitute driver or a group to share a car as a team.
COMPETING MODELS:
Any car or truck with any transmission-motor combination in a rear wheel drive vehicle which came factory
stock with a four cylinder engine on which 13” or 14” rim must be bolted onto the rotor. No rear engine
cars are allowed. Only domestic trucks can swap engines with other manufacturers.
ENGINE:
The engines will follow the Wissota Mod four engine rules except where noted. Engine must be a stock
factory issue 4 cylinder with maximum 151 CID or 2500cc and remain in factory stock position, and must
come stock for that make and model of car. Engine components may be interchanged from all year’s
motor available. Only Toyota may swap TO large engine displacement not available in the year model
of car (must not exceed 2500cc). No rotary, turbo or high performance engines allowed. Engine may be
bored to allow the use of a maximum .060 oversize piston. D-port heads and intakes allowed No 2500cc
Ford engines allowed. Mini trucks may swap engines to other manufacturers as long as it complies with
mod 4 rules.
1
2
Bore, stroke and rod length shall be:
Bore Stroke Rod
GM 151 4.000” 3.000” 6.000”
GM 140 3.500” 3.625” 5.700”
Ford 2000 3.570” 3.030” 5.000”
Ford 2300 3.781” 3.126” 5.200”
Chrysler 2.2 3.440” 3.620” 5.945”
Intake and exhaust measurements must be:
Intake Exhaust
GM 151 1.720 1.500
GM 140 1.625 1.375
Ford 2000 1.653 1.418
Ford 2300 1.739 1.500
Chrysler 2.2 1.600 1.390
Engine
•
No Duratech engines allowed.
•
Grinding is allowed on crankshaft rod and main bearing journals only. No dual overhead cams
allowed. Any flat tappet cam with .525 lift measured at the value with no roller followers. No
portinga polishing. Solid lifters allowed. Any valve spring, valve spring retainer must be steel,
valve face diameter must be stock to trat engine. Longer valve stems allowed to correct valve
train geometry.
•
No gasket matching. No multiple valve or turbo heads. Adjustable cam gears are allowed. Fan
and drive pulleys diameter may be changed. Decking the block and milling the head is allowed.
No marine parts.
•
No stroker cranks, long rods, aluminum rods on aftermarket rods allowed. Forged and racing
pistons are allowed.
•
Stock intake manifold with no modifications other than block off water intake passage. Exhaust
manifold on header must run underneath the car, not through it.
•
No roller cams on components in the head are allowed.
•
Pump gas only. Aviation fuel allowed. No octane on alcohol booster allowed. No nitrous oxide
on nitro allowed. Fuel cells are required. Safety personnel may require additional bars to protect
the fuel cell. Cell must be in a steel can.
•
No fuel injection on related parts (manifold)
•
Stock downdraft gas carburetor only.
•
Two-barrel carburetors may be wired up to and including Holley 500.
•
Removal of chokeplate is allowed.
•
Carburetor air horn must not be modified.
•
Adapter plate and gaskets will not exceed 2 inches in measured height from the top of the in-
take manifold to the bottom of the carb plate on a Holley/Weber 5200 carburetor. Any carburetor
other than the Holley/Weber 520 Series (Pinto/Mustang) carb will be required to use a restricter
plate #135-1955 (Speedway).
•
Alternative 18-gauge sheet metal plate 1.100” and/or 0.005 in the throttle bores may be avail-
able at the parts trailer for a much lower cost.
•
No blowers on turbo chargers allowed
•
Stock fuel on electric pump allowed – rollover safety switch mandatory on electric fuel pumps
•
Mandatory 2” hole that provides access to measure flywheel thickness must be placed in the
bell housing.
•
Transmission bell housing must have scatter shield installed
•
•
•
•
•
•
•
All gears must remain stock OEM – subject to check
No brake control devices. All 4 wheels must have OEM breaks. All 4 wheels must lock up.
No aluminum or nonferrous flywheels. OEM flywheels only, no drilling flywheel to lighten. Must
not be turned thinner than minimum Thickness of 1”, and a minimum diameter of 10.125”, not
including the ring gear. Balancing recommended.
Must have a working clutch (No couplers).
No racing power steering pumps on alternators - must be OEM.
OEM brakes on all four corners of the car.
No electric power steering.
*Track reserves the right to tear down an engine at any time to promote fairness of the class.
Replacement gaskets will be provided if found legal.
Welded or spooled rear ends are required. Any gear allowed in stock rear end housing for year and model
and make of car. The transmission must remain stock for the engine. Automatic transmissions must use
stock torque converters.
Holley 4412 carburetor is allowed. Casting number L6R1998 main body number R4412-14 or R4412-
15. Cannot remove air horn. Can not have adjustable screw in air bleeds. Must meet all 4412-500 CFM
tech tool measurements. A Holley 4412 carburetor may only be used with Wissota spacer/restriction from
Speedway motors p/n 135-1955 with 11/4” max thickness with gaskets.
•
Single 5200-series pony car carb; E.G.R. plate O.E.M. to engine, if used, must be bolted - not
welded - to manifold. On GM 151 c.i.d. engines, the use of a redrilled EGR plate, bolted - not
welded - to the manifold, is the only acceptable mounting. Choke plates may be removed. No
milling or grinding on choke tower, top of carburetor or intake. Chrysler and GM 151 c.i.d. -
large venturi goes outside. Carb fuel inlet is always forward. Number 6500 carburetors are not
allowed. Replacing throttle shaft bushings in carb base is allowed.
Bottom of carburetor can be no more than 1” above the E.G.R. plate [or intake manifold, if no
E.G.R. plate is used]. No spacer between E.G.R. plate and manifold may be used. EGR plate,
if used, may be modified. No devices can be added to the inside of the intake to increase or
redirect the airflow.
Carburetor throttle plate & bore must be stock: primary throttle bore 32.0 mm maximum and
secondary throttle bore 36.00 mm maximum. Primary venturi diameter 26.00 , secondary bore
27.00 mm maximum.
No floatless carburetors allowed. EFI or mechanical injection is NOT allowed. Throttle plates
must be round.
Body + Chassis
Roofs and truck lids may be gutted. Windshield must be replaced with a minimum of three 3/16” diameter
bars or 1/16” full screen supported in the center of the car windshield with a ¾”diameter bar.
Replacement tin is required to cover lower portions of the rear deck. Wheel wells may be radiused
a maximum of four inches from stock. Bumper corners must be capped or covered with belting.
Frames may be reinforced. May reinforce inside of bumpers and inside of frame rails. Brace pipes which
extend forward from the roll cage to the front hoop will be allowed to remain outside of the frame rails as
long as they angle into the front loop and stays inside and behind the bumper cover.
Those who are running cars with strut suspension will be allowed to brace the upper frame under the
3
•
•
•
hood and should cut their front bumper even with the outside of the hood and fill in and cap the end of
the bumper. Connecting front and rear stubs is allowed.
Any springs or shock that will fit stock location is allowed. No racing struts allowed. No adjustable .
screw jacks allowed.
Factory bumper cover and grill covers may be used (Mustang).
Total weight of car and driver 2350
Any car radiator allowed, mounted in stock location. Cars may run electric cooling fans. Radiator
mounting girdles may be removed.
Lettering will follow Wissota rules.
Numbers must be 18” tall and in a contrasting color to the background color. Must be displayed on both sides
of the car and roof facing the grandstand.
Use a color that can be seen on read for the scorers. Driver assumes all the risk for the readability of his/her
number. If not in a color that can be seen, you may not be scored properly.
All sheet metal must remain intact. Front fenders are required. Door skin and other body parts may be replaced
with tin minimum of 24 gauge or .040 aluminum and must conform to body contour. Inner door panels and
dashes may be removed. Spoilers are allowed with a maximum 5 inch height, with 6 inch spoiler supports.
The Driver’s compartment must be securely braced with welded roll bars of at least 11⁄2” OD tubing.
(NO muffler pipe, aluminum pipe or conduit allowed.)
There must be a complete four (4) point roll cage all around the driver with a three (3) inch head clearance
minimum, constructed with a minimum of .095 wall thickness.
There must be at least three (3) bars in the driver’s door and one (1) bar in the center of the roof. Full cages
must have a bar added down from the top left front of the top loop to the uppermost sidebar, so the cage
doesn’t collapse during a rollover (vent bar)
Center cage must have a brace bar connecting the front, back and driver’s door upright bars. Upright bars
must be welded to 6” x 3/16 plate minimum, which must be bolted to the floor with four (4) 3/8” bolts with
corresponding plates under floorboard
Plates may be welded to existing sub frames. A 1/16” plate covering the driver’s side door bars is required.
NOTE: Safety person may approve other mountings provided they are safe and do not give the car a
competitive edge.
Doors must be welded or bolted shut. Grills may be removed. Rock deflection screens may replace grills.
Stock roof and window support must be used for safety concerns
Maximum body width of a car will be 713/4” (this measurement is based off of a stock fox body mustang).
This includes any side/rub rails on nose pieces.
4
Rub rails must be tight against the body and be no more than 2” off the body.
*The bodies will need to be legal by July 1st, 2026.
Safety
Cars must have:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Racecievers must be used.
Driver side window net.
5-point 2” or 3” wide belts. Month, year, and date of manufacture must be on all belts. No OEM
factory-type shoulder belts on straps will be allowed. Metal-to-metal buckles are required on the
shoulder harness and lap belt. The harness must be mounted in at least (5) points below the
drivers shoulders.
Helmets – All helmets must be rated SNELL SA 2020 or SFI 31.1/2015 or newer. Must have a
face shield + eye protection.
Head and neck restraints are highly recommended.
Roll cages must be constructed of 1.5” tubing. .095 wall for all of the 4 point cage and the 2
support bars running from top of roll cage to the rear of the vehicle.
Fire retardant racing gloves are mandatory
Exhaust systems must be mounted in such a way as to direct exhaust away from the cockpit
area of the vehicle and away areas of possible fuel spillage. Car number must be present on
the last piece of exhaust. All cars must run a muffler.
Driving suits and gloves of a flame-retardant nature must be worn by all competitors. If the suit
is a 2-piece both top and bottoms must be worn
Recommended is a 1-piece 2 layer suit of fire resistant material and underwear, socks,
shoes, and hood.
A full containment seat is highly recommended. When mounting the seat, a minimum of 4-3/8”
bolts must be used.
While sitting in the seat – driver’s head must be below the roll cage. This will be checked for
safety during inspection.
Ballast may be added provided that they are painted white and the car number is welded on
clearly marked. Any car loosing ballast during a race will be disqualified. All ballast must be
under the deck. No ballast allowed in the cockpit.
Battery must be contained in a sealed battery box.
Drive shaft must be painted white. Steel drive shafts only. Drive shaft hoops are required.
Fuel cell must be enclosed and separated from driver compartment.
Tires + Wheels
•
•
•
•
•
Either Wissota Mod 4 tire is allowed. If using the newer tire – only used tires are allowed. Tread
depth – 21/128 on .165 will be measured on the middle 2 ribs. Grooving will only be allowed on
crosshatch on the face of the tread with a #2 blade only. Same as Wissota. We will be checking
on the newer tires. These will be the only racing tires allowed.
Up to 7” wide wheels allowed. 13” or 14” inch wheels allowed.
Beadlocks will be allowed on front right and rear right.
Offset wheels are allowed. Spacers up to 1” behind the wheel is allowed.
No snow tires/ tires with snow like tread or retreads.
Tear Down Protest
•
Any mini stock driver wanting to request a tear down of another driver must have raced at least
50 percent of the races raced.
5
•
•
•
Example – if 4 scheduled races have been raced, the driver protesting must have
raced 2 times before at least.
Any driver wanting to tear down may only tear down 1 car any given night.
Drivers may only protest 2 times in a season.
Opening weekend and stamped-only track will tear down if deemed necessary.
For the protest the head and intake will be removed. Various measurements will be checked. Bottom
end will be scoped with the scope. Bore and stroke will be checked. Flywheel will be checked from the
bellhousing hole. No need to pull clutch on tr**ny.
Before the feature starts, $300 cash must be given to the mini stock tech inspector (Tim Carlson) in an
envelope stating the car they want torn down. This will not be accepted after the start of the feature (must be
done at intermission). Track officials will be notified of the car that will be protested. The driver doing the protest
must start the feature and finish on the lead lap. If the driver does not finish the feature, the protest will not go
through. The car that is being torn down must finish the feature also. Money will be returned to protesting driver
if protest does not go though.
Protest:
•
• Tech man will inspect the car of the driver protesting to make sure they are legal also.
• Only people allowed in tear down area – car driver, 1 pit crew member, 4 cylinder tech person,
promotor + security. (head tech may be asked for clarification if mini stock techman has
questions).
• If found legal: the driver will be awarded $250 from the protest money.
• If found illegal – driver forfeits all money and awards from that event. All pints from the year are
lost. A $500 fine will be imposed and illegal parts will become property of Bemidji Speedway.
Driver will be suspended for 2 weeks and fines must be paid in full before racing again.
*Refusal of teardown will result in loss of track points and a 30 day suspension from the mini stock class.
Rules may be amended on revised at anytime to ensure a fair and competitive race program.
Refusal on Termination of Inspection
Any driver who refuses to allow a pre-race on a minimum specification inspection to be conducted
will not be allowed to compete in the racing event.
Any driver who refuses to a post-race inspection, or who terminates an inspection in progress, shall
be fined $1,000, suspended for 30 days, lose all season points, and forfeit all money and awards for
that event.
Any driver on car that is found with illegal parts at a non points race - example, Paul Bunyan
Stampede - will be fined $500 and suspended for 30 days and forfeit all money and awards for that
event. The suspension will start at the beginning of the next race season for 30 days.
The Bemidji mini stocks will follow the Speedway rules for all events that they attend. Even though
the point season is over - the Bemidji mini stock rules will be followed! It is not a free for all at non-
point races. There will be consequences to not following the printed rules.
When going thorugh a pre or post race inspection - any illegal parts that are found will become
porperty of Bemidji Speedway. Refusal to give up the part will result in a ban from Bemidji
Speedway.
The Bemidji Ministock Class will use the Wissota Code of Conduct for diver and crew behavior.
Thank you.
•
•
•
•
6
