Magic Valley Speedway            
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Mini Stocks

Magic Valley Speedway Mini Rules 2019

10.1       DEFINITION.

10.1.1    The word stock will mean unaltered as originally factory produced and installed for make. All Cars and trucks will be stock unless otherwise specified within these rules.


10.2.1    1960 newer 4 cylinder sedans, coupes, or pickups.

10.2.2    Any front or rear wheel drive non-turbo 4 cylinder approved. Fiero models not approved.

10.3       ENGINES

10.3.1    Must be same make as the body.  4 cylinder only.

10.3.2    Only factory produced OEM parts and components will be approved unless otherwise specified.

10.3.3    Connecting rods of  aftermarket supply are approved of similar weight and material

10.3.4    Intake manifold will be stock with factory casting numbers. No porting. No grinding or modifications of any kind allowed other than the 4 hole aluminum intake for 2.3 Fords and Chevy Monza, plenum (plenum means inside of manifold) area may be cut down 1" maximum in order to run the class carburetor.  Must pass tech approval.

10.3.5    Header or exhaust manifold type is optional

10.3.6    Flywheel may be cut or surfaced but must retain factory casting numbers.

10.3.7    Clutch disc and pressure plate will be stock type replacement only.

10.3.8    No porting of cylinder heads allowed.

10.3.9    Stock type rocker arm assembly only.

10.3.10  Pistons, valves, and valve springs may be factory type replacement of similar weight and material.

10.3.11  SPRINGS/RETAINERS/LOCKS– May be aftermarket to match cam. Double SpringO.K. May machine heads to use double springs.

10.3.12  Fuel pumps must be factory type replacement. Electric pumps must have oil pressure shutoff switch. (If engine dies, fuel pump must shut down immediately.)

10.3.13  Engine must remain in stock location.

10.3.14  One two-barrel carburetor only. Any OEM 2bbl carb, or Holley 7448 or 4412 approved. Maximum 1” adapter or spacer plate allowed. Two Throttle return spring will be required.

10.3.15  Injection cars must have OEM fuel log, intake and throttle body.

10.3.16  Air cleaner or butterfly cover required.

10.3.17  Oil pans may be over-sized, interior baffles allowed. Claimer pan approved. Oil coolers and remote filter locations are approved. Oil coolers must be mounted outside of the driver’s compartment. Must be located forward of the front firewall and rearward of the radiator.

10.3.18  Camshafts may be after-market type of any manufacturer. Roller cam and lifters not approved, unless OEM for engine being used.

10.3.19  Cam timing gear is optional.

10.3.20  After market and speed parts not approved in the above section will be subject to removal at track discretion.


10.4.1    Body and chassis must be of the same make and model.

10.4.2    Body must be complete for declared make and model. Aftermarket steel panels approved.

10.4.3    Bodies to remain stock in appearance. Destroyed panels must be replaced or repaired.

10.4.4    Fenders and quarter panels may be trimmed for tire clearance. Trimming not to excee3” from top of the tire.

10.4.5    All exterior molding and lights must be removed. Including rear and side glass.

10.4.6    Windshield optional. If removed it is recommended that it is replaced with a maximum of ½” X ½” mesh screen covering the entire opening and be securely mounted. Lexan windshields are approved. Windshield opening must have one or two tire bars” securely welded into opening to prevent a tire like object from entering the driver’s compartment. Mirrors optional.

10.4.7    Front inner fenders may be removed. Both inner door panels may be removed. All other inner panels must retain stock location and be complete. Hood and rear deck lig, roof panel and inner quarters may be skinned. A hole in the hood may be cut to allow air cleaner clearance.

10.4.8    Inner panels in trunk area may be removed/replaced.

10.4.9    Exterior nerf iron is not approved

10.4.10 Wings and/or Rear Spoilers are optional.    Any wing must be securely mounted to the roof or trunk area of the car and measure no larger than 52 inces long by 40 inches wide and be no taller that 8 inches. Side Panels shall be no taller than 18 inches.   Any rear spoiler will not exceed 48' in width and shall not exceed 18'' in height as measured from the deck, side panels are approved but shall not exceed 18 in height at the spoiler attachment point and shall be a maximum of 1'' in height at the forward attachement points.

10.5       BUMPERS

10.5.1    Bumpers will be stock for make and model.

10.5.2    Fabricated tube style bumper may be used if covered by a factory stock rubber bumper cover or After-market front bumper cover.

10.5.3    All rear bumper covers may be stock or aftermarket type.

10.5.4    Front and rear bumpers may be strapped to the fenders or quarter panels with a minimum 1/8” thick steel strap. Recommended piece 1 ½” X 12” should be securely bolted or welded in place, unless covered by a bumper cover.

10.5.5    Front bumper may be reinforced for radiator protection. Two upright bars and two cross bars not to extend beyond the front bumper. Not to be connected to the roll cage in any way. Exception, rule number 10.6.5 below.

10.6       ROLL CAGE

10.6.1    A six-point roll cage is mandatory. The roll cage must be mounted to the frame, maximum seven points to the frame.

10.6.2    Main bars must be a minimum 1 1/4” black pipe, 2” O.D. maximum, with a 1/8” wall thickness, weld or securely bolt to the frame. Braced not less than half the height of the main bar back to the frame. At least one diagonal brace in main bar. Minimum three sissy bars on driver’s side and two on the right passenger side.

A minimum 1 1/2” O.D. roll bar tubing or manufactured roll cage kits are acceptable. No exhaust tubing or galvanized pipe allowed.

10.6.3    Gussets are required on all 90-degree joints.

10.6.4    Unibody. Roll cage must be securely fastened to the floorboards by welding 1/8” thick minimum plate, 4” X 8” or 6” X 6” on top and/or underneath the floorboards using 3/8” bolts per mounting, or cage may be directly integrated into the sub frame at all main points with full circumference welds.

10.6.5    Front hoops allowed to penetrate the firewall. Hoop bracing intergrated into strut towers is approved. Radiator support may be integrated into the hoop. All mounting to be ahead of the upper A-arms.


10.7.1    Automatic transmission use is optional.

10.7.2    Transmission must be stock for make.

10.7.3    Torque converters will stock stall speed.

10.7.4    Transmission coolers and cooler lines shall be contained outside of the driver’s compartment. It also must be located in front of the front firewall or behind the rear firewall, no exceptions.

10.7.5    Manual gearboxes will be stock for make with no alterations.

10.8       REAR END

10.8.1    Must be stock for make and model.

10.8.2    Gear ratio optional.

10.8.3    Unlocked differentials are optional

10.9       SUSPENSION

10.9.1    Suspension must be stock with the following exceptions.

10.9.2    Shocks and struts must be stock type and mount in original location. Notching of Strut tower bolt holes is permitted. Replacement tower plate approved

10.9.3    Front coil spring type, size and height is optional. No adjustable spacers on top of the spring allowed. No weight jacking bolts or devices of any kind allowed. Torsion bars will be stock or stock type replacement only.

10.9.4     Leaf spring cars will remain leaf spring cars. Stacks may be altered. Any spacers or lowering blocks used in the leaf stack must be securely mounted. Front mounts will be stock. Rear shackles/connectors may be stock or fabricated. No threaded or adjustable jacking devices approved.No chains or stopper may be used to stop suspension movement.

10.9.5    Use of twisties or spring rubbers are approved.

10.9.6    Rear coils springs of any type approved. Shims or spacers may be used to raise or lower either corner of the car.  No threaded or adjustable jacking devices approved. Spring pockets may be altered or replaced, but will remain in stock location.

10.9.7    Sway bars will remain stock for make and must be mounted in stock location.

Connection method to lower control arms is optional. Sway bars may be adjustable. Poly bushings approved. No heating, cutting, welding, grinding, or bending of any suspension component allowed, unless otherwise noted.

10.9.8    A-arms must be stock for MAKE AND MODEL, this means: UPPERS AND LOWERS. Poly or steel bushings approved.

10.10     BRAKES

10.10.1  All four corners must be stock and in working order. Stock swaps for larger or disc brakes allowed in front.                                                                                        10.10.2  Rear disc brakes are not allowed, unless stock for make and model.

10.11     WHEELS

10.11.1  Steel Wheel not to exceed 8” in width. White spoke type wheel or better  mandatory on the right front corner, not to exceed 8” in width.                                  10.11.2  13” or 14” or 15" wheels are approved.                                                     10.12     TIRES                                                                                                        10.12.1   Hoosier 700                                                                                               23.5/7-13 available                                                                                                   23.0/7-13 available                                                                                                 23.5/7-15 available                                                                                                         23.0 and 22.5 Hoosier Sportsmans will be allowed through the 2014 racing season. All tires must be purchased at Magic Valley Speedway.                                                10.12.2  Chemical softening of tires is prohibited.

10.13     RADIATOR                                                                              10.13.1  Only one radiator allowed.                                                                        10.13.2  Must mount in stock location.                                                                    10.13.3  One gallon over flow tank required.

10.14  FUEL SUPPLY                                                                            10.14.1  Commercially produced fuel cell is mandatory. See Speedway Specs for installation instructions. exception: stock gas tank may be used and must remain in place if it is located forward of rear axle.

10.14.2  Rubber line passing through the drivers compartment will be contained in conduit or pipe from the front firewall to the rear firewall.                           

10.14.3  Racing fuel approved, no alcohol allowed.


10.15.1  Ignition will remain stock for make, after-market coils and/or replacement ignition modules are approved. Distributors will remain stock for make, HEI and single point approved.

10.15.2  Alternator is optional. Car must start on its own power.

10.15.3  See Speedway Minimum Specifications for battery mounting requirements.

10.16  SEAT

10.16.1  Aluminum racing seat required. Steel framework around the seat is recommended. Installation is subject to tech approval.


10.17.1  Mechanical or electric fan only, after-market allowed.

10.17.2  Fan must be shrouded, must cover both sides and top.


10.18.1  Participants car must be equipped with a 2 ½ lb fire extinguisher within easy reach of the driver, must be full at all times and have a readable gauge.

10.18.2  Each participant must keep a second fire extinguisher in his/ her pit area. The extinguisher will be a minimum 2 ½ lb or larger.




10.19.2  Left side window net will be fitted with a seatbelt connector for quick release.


10.20.1  No minimum ride height will be enforced.


10.21.1  See Speedway Engine Protest procedures.

10.21.2  See Speedway Chassis Protest procedures.


10.22.1  Minimum total weight for 2 valves per cylinder engines as weighed with the driver wilbe 1.0 lbs per cc of engine displacement. Includes overbore.

10.22.2  Minimum total weight for cars with engines that have more than 2 valves per cylinder as weighed with the driver will be 1.05 lbs per cc of engine displacement. Includes overbore.

10.22.3  Maximum left side weight percentage as weighed with the driver will be 55.0%

10.22.4  Engine size must be noted in a minimum 6” tall letters on the hood or top left corner of the windshield in easy view of the scale master.

Declared Weight must be noted instead of motor size for Multiple Valve per cylinder cars.

10.23  RADIOS

10.23.1  One-way radios (scanners/ race scan) are required, must be on race control channel at

all times.

10.23.2  Two-Way radios not permitted.
11.1 MVS Mini Mods allowed Bone Stock 4 cylinders 10" Wheels 3025-3035-3045 
Hoosier take offs only.