2022 MCCTA

Official Montana 500 Website


Updated OCTOBER 10, 2021

Note: All cars that tour along must meet the rules flagged with a *.
Note: 2021 newly adopted or changed rules in green italics.


A1These rules dated October 10th, 2021 supersede all others. These rules are intended to outline current acceptable practices. Deviation beyond these practices may result in disqualification or time penalty. Directors are responsible for interpretation of all the rules pertaining to the Association and assessment of time penalties. Decision of the Directors is final.

A2. * All cars must comply with Montana license and insurance requirements.

A3. * No alcoholic beverages will be allowed in competing cars. Substantiated violation is cause for disqualification.

A4. * Drivers exhibiting un-sportsman-like behavior or demeanor will receive one warning.  Second infraction may result in disqualification upon review and affirmative vote of 2/3 of the remaining drivers.

A5. Not more than two people are allowed per endurance car while under time.

A6. * All drivers and relief drivers must be a paid-up member of the MCCTA.

A7. * Do not tailgate or draft any vehicle.  All drivers must maintain a safe following distance, but no closer than the ratio of 10 feet per 10 mph, i.e., 50 feet at 50 mph and so on.  Report any infraction to the President.  One infraction incurs one warning, a second infraction incurs disqualification. 

A8. *All participating cars must have attached or placed directly on both sides a sign with name of sponsor or owner and hometown. Use three (3) inch letters preferred.

A9. *Violating posted speed limits.  Any driver exceeding the posted speed limit by 6 miles per hour (MPH) will incur a 6-minute penalty.  The 6-minute penalty will be increased by 1 minute per every mph over the posted speed limit.  I.e., 5 mph over posted speed limit has no penalty, 6 mph over incurs a 6-minute penalty, 10 mph over incurs a 10-minute penalty. 

A9.a. Challenge Exception.  Electronic device challenging the Radar Gun reports.  If you have evidence from within the posted speed limit zone from an electronic device that clearly indicates your vehicle, the speed limit sign, and your vehicular speed, you may use it to challenge the Radar Report.  Show your evidence to the Directors and they will decide to impose the Radar Report penalty or not. 

A9.b.  The President will pick one non-driver person to be in charge of the radar guns.  This person will select the locations for radaring and other non-driver persons for running the radar guns.  This person and helpers are on their honor to not discuss the radar location whereabouts with anyone else.  (October 10, 2021.) 

A10. Drivers are responsible for following the prescribed route. Failure to travel the entire prescribed route will result in an assessment of slow time for that leg plus a penalty of fifteen minutes. Flaggers or signs may be posted as deemed necessary or advisable.

A11. Routes will be planned to avoid running through stoplights under time.

A12. * All Ts will be available for subsequent inspections at any time. Any member may initiate an inspection at any time, subject to approval by a majority vote of the director’s present. 

A13. * All drivers and relief drivers must sign an Endurance Run Waiver and Inspection Form.

A14. Every year new inspection seals will be placed on each competing car.  Drivers are required to remove and properly discard existing seals and seal wires from the head bolts, carburetor bolts, and windshield sticks before inspection begins.  New seals and new seal wire will be installed by the inspectors each year.  (October 10, 2021).  Also see Rules B2d, B2k, and E3. 

A15. Placement position results for cars that do not complete the entire endurance run will be based on actual mileage completed.


B1. Body must be painted. Body parts must be stock for year of car, sawed off touring cars allowed. Cars must have four fenders, splash aprons, running-boards, and if so equipped: front splash apron, dash, and radiator shell, and all replacement body parts must be made of metal. Chassis parts may be assembled from any year T parts. Gas tank must be stock for that year of car and mounted in stock position. Exception:  “1925 and earlier cars may have gas tanks raised 1-5/8 from the stock position”.  No fuel additives are allowed. Cars must use straight automotive pump gas as fuel during the Endurance Run time, starting with inspection and continuing until the end of the Run.

B2. All T’s must be assembled from stock parts and/or reproduction parts equal to stock specifications, with the following exceptions:

B2a. * All competing cars must be equipped with two headlights and one or more rear stop and tail light in working order. The stop and tail light does not have to be a single unit. 

B2b. * Horn of any type in working order required.

B2c. * Rear view mirror of any type required.

B2d. Windshields must be stock for year of car. No altering. Must have safety sheet or safety plate glass top and bottom. Windshields to be completely closed and sealed by an inspector. 

B2e. * Padded seat and back rest of any type required.

B2f. Original turtle deck may be replaced by some type of substantially built box or turtle deck. Minimal length and width equal to size for stock turtle deck on that year of car, with floor, sideboards and end-gate. Sides and end no less than six (6) inches high from the floor and made of no smaller than 3/4″ wood.

B2g. Fuel line not to exceed 3/8″ I.D.

B2h. * At least 36 inches of 1 1/2″ exhaust pipe required, properly attached to and extending from the exhaust manifold.  Exhaust pipe wrapping on the first 36 inches of the exhaust pipe not allowed. (October 11, 2015).

B2i. Only stock cast iron or stock aluminum or new manufactured intake manifolds with ports not to exceed 1 1/8″ diameter are allowed. No grinding or performance enhancing alterations of the intake or exhaust ports allowed. Chaffin’s manifolds under current production are allowed as long as the gland ring is 1 1/8” or less.

B2j. Only stock Ford roller type, New Day, Anderson flapper type timers, Crystal or TW timers allowed.  A Rush Roller is allowed in Ford Timers.  Quick couplers NOT ALLOWED in timer wires. 

B2k. Holes must be drilled through the heads of the following bolts for seal wire: two center head bolts, middle two small pan bolts, and a hole must be drilled through the threaded end of both bolts that fastens the carburetor to the intake manifold. Please paint the heads of the drilled bolts a contrasting color.

B2l. Only NH swayback or Ford “F” swayback carburetors allowed. Carburetor must be complete, including choke butterfly.  The Association’s 0.710″ gauge  MUST NOT go through the carburetor from either side. The club’s W gauge shall not pass from the choke side of the carburetor. Carburetor must conform to the diagram as printed.  No material can be added to the interior of the carburetor. The spray needle diameter must be 1/8” +/- .015”.

B2n. Only Model T type wire wheels, Model T type wooden spoke wheels, Model T type disk wheels, Model T type aluminum spoke wheels, Model A 21″ wire wheels, or 30 by 3 1/2″ wire wheels are allowed.   Radial Tires not allowed (2019.)

B2o. Only stock Model T or Ruckstell rear-ends and axles with 3.64: 1 Ratio:

– standard eleven tooth pinion
– forty tooth ring gear
– stock roller bearings
– Ruckstell rear-ends must be locked in high

-Modern drive shaft pinion bearings allowed in the pinion spool.  (October 10, 2021).

B2p. Cast iron or aluminum pistons of stock Model T type required. Cast iron pistons must have a full set of .250″ width rings in place. Aluminum pistons must have two (2) .125″ width compression rings and one (1) 0.1875″ width oil ring in place. Pistons must conform to the attached diagrams. Refer to Illustration for Piston Dimensions

B2q. There must be one stock piston, rod and cap assembly in the engine. Exceptions: Cap may be drilled for dipper, and grooved for oil. The other three (3) assemblies can be balanced to this one. Piston is not to exceed a height of .400” above the head gasket.

B2r. Rods must be Model T Ford script. Maximum center to center distance of 7.030″ measured from center of rod journal to center of wrist-pin.

B2s. Any cast iron original Ford script head is allowed, but the combustion chamber is limited to 270cc minimum. The head will be measured without the head gasket, without spark plugs, and the spark plugs holes will be plugged with clay to be flush. One stock combustion chamber is required, the other chambers to mimic the stock chamber. No material can be added to the combustion chamber to equalize.

B2t. The crankshaft must be Model T Ford Script with a stock stroke of four (4) inches + / – .030. Chroming, hardening or grinding of journals allowed, not to exceed 1.250″ maximum or 1.208″ minimum diameter.

B2u. For all valves use a minimum stem diameter of 5/16″, a maximum head diameter of 1.500″ and seating face of 45 degrees. Use either pins or two-piece keepers. Radiused, 45 degree or three angle seat grinds allowable.

B2v. Any cam that doesn’t require modification of the block may be used. Bearing bores must be standard size, no relieving of the bearing bores. Adjustable timing gears allowed.

B2w. Adjustable flat tappet lifters (push rods) of stock dimensions, stem oversize to 1/32″ allowed.

B2x. Only stock Model T Ford and Model A Ford valve springs are allowed.

B2y.  Original Ford u-joints modified with needle bearings allowed.  (October 10, 2021.)


C1. * Emergency brakes must be in good working order.
C2. * All transmission bands must be in good working order.
C3. * Complete set of floorboards required.
C4. Rebuilt or new radiators allowed. Must be built to stock dimensions including tanks and side brackets.
C5. No modifications of the inside oiling system allowed.
C6. Non-Model T style and size tops not allowed.
C7. Throat of carburetor may be smoothed as long as the Association’s .710″ gauge does not pass. No altering of the basic design of the carburetor allowed. Carburetor must be complete including all butterflies, adjusting needle, and stock spray needle. Choke and throttle rods must pass a visual inspection for stock uniform shaft dimensions with no obvious modifications. Butterflies must be original size.
C8. Bolts on wishbone at rear of pan must be safety wired. Front wishbone accessory braces on pre-1920 cars allowed. Use standard wishbone sizes.
C9. Use stock configuration spring sets with a minimum of seven leaves per spring set.
C10. External auxiliary accessory type brakes are not allowed.
C11. Belly bands are allowed and if the motor mount breaks the car takes the standard penalty. The belly bands cannot be used for support at any time.
C12. Accessory pan arms are not allowed except for as an emergency repair while under time.
C13. Steering dampeners are not allowed.
C14. Ignition battery must be 6-volt type.
C15. Accessory battery charging devices must be disconnected.
C16. Battery disconnect switches and fuses are allowed in the primary circuit, excluding the ignition system.
C17. Original type ignition switch required.
C18. Cylinder bore not to exceed 3.825″ maximum or 3.750″ minimum.
C19. Counter-balanced crankshaft not allowed.
C20. E-timer is not allowed.


D1. Optional equipment must serve the original purpose and no other purpose. 

D2. Optional equipment includes:
-Balancing of rotating parts
-Band material type-Body color
-Bronze or roller thrust washers and neoprene seals on Model T or Ruckstell rear ends and axles
-Camshaft bearings and seal 
-Camshaft gear may be drilled
-Camshaft timing gear material type
-Coil box material type
-Engine splash pans

-Exhaust Pipe Wrap after the first 36 inches (2015-Oct-11)
-Fan use and type
-Fourth main type
-Gas strainers allowed
-Gas tank.  1925 and earlier cars may have gas tanks raised by 1-5/8”. 
-Grooving and drilling of the rod bearings and main bearings 
-Hardened valve seats
-Hood use
-Hot air stove, original type
-Internal timer material type
-Knurling of piston
-Maximum of one outside oil line allowed
-Muffler use and type
-Multi-piece piston rings
-Neoprene seals use
-Rod bolts and nuts choice
-Shock absorber use and type
-Spare tires and type of carriers
-Stainless steel and swirl polished valves
-Timers, ball or needle bearing rollers, Anderson flapper, Crystal timer, Ford Roller, New Day timer,      Rush Roller, and TW timer.

-Triple gear bushings may be replaced with needle bearings and hardened flywheel triple gear pins.  (October 10, 2021).
-Tops of open cars use
-Transmission oil screen and steel band drums allowed
-Turn signals 
-Use and type of high-speed clutches, such as Watts and Turbo 400
-Use of offset key between crankshaft timing keyway and the crankshaft timing gear keyway
-“V” type belt and pulleys
-Water pump design and use
-Windshield wiper of any type
-Zerk fittings in place of oil and grease cups


E1. Timing will begin as designated for each car whether or not the car is on the starting line. Starting times can be adjusted at the timer’s discretion. If the timers recognize a beneficial savings in time, a lagging car may be sent out ahead of its designated time. Usually this will be discussed with the Directors ahead of time. Time will start for this car when it leaves the starting line.

E2. * Each car will come to a complete stop before starting at the timer’s direction.

E3. Removal of head or pan while at stop (not under time) or on tour day, if tour day occurs during the endurance run, will impose a time penalty of 1 hour. Report this infraction to the directors immediately. Removal of head or pan under time must be reported to the directors at the first opportunity for replacement of seal.

E4. Changing the carburetor imposes a time penalty of 15 minutes. Report the infraction to a director immediately. Replacement carburetor must meet the requirements stated in the Inspection Rules.

E5Trailered cars will receive slow time.  (Penalty rescinded October 10, 2021.) Cars trailered on the last day are not eligible for prize money or trophies.

E6. Replacement of complete engine is cause for disqualification.

E7. All Directors are expected to attend the teardown. The top car will be torn down immediately following the last flag. Additional teardowns will be put to a vote of the Drivers. Drivers will be allowed to view the teardown from a respectable distance.  Disruptive people will leave the area. (October 10, 2021). Directors will discuss and vote to accept or reject items of question.

E8. The first-place car will be torn down by a panel of five inspectors. The driver in the top position at teardown cannot be an inspector, but the next five place drivers are required to be inspectors for teardown. If the first-place car is disqualified, the next place lower will be inspected, until a car has been found qualified. All inspectors must vote.  Any driver has the right to consult with an inspector on any issues concerning the cars.  The five teardown inspectors have final say in what is brought to the vote of the drivers.   

E9. The Tear-Down Manual is a supplement to printed Rules. If there is conflict then the printed Rules will take precedence.

E10.  Homologated cars will be placed higher in the finish order than non-homologated cars.  (October 10, 2021.)

The Montana 500 is Sanctioned by The Montana Cross Country T Association.