Home of the SK Modifieds®

2016 SK Light Modified Rulebook


20E- 10.8 TIRES

20E- 10.6 REAR AXLE


The rules herein shall refer to Stafford Motor Speedway as “SMS”. These rules are intended to create affordable and fair competition. While they offer a good outline, every item cannot be covered by a written rule. If you have questions regarding something not detailed in these rules, please consult an SMS Official for clarification before proceeding. These rules are for SMS only with no expressed or implied agreement with any other speedway or series as to their interpretation, implementation and method of inspection by their technical inspectors and officials. No car, component or equipment will be considered as having been approved by reason of having previously passed through inspection unobserved. No car, component or equipment will be considered as having passed inspection for the event until the finish is made official.  All engine models, equipment changes, or modifications not specifically addressed in the rule book by SMS must be submitted in writing for consideration of approval on or prior to September 2, 2016 unless otherwise authorized by SMS to be considered for competition for the 2017 season. All equipment is subject to the approval of SMS Officials. You may be assessed penalties including but not limited to: added weight, fines, loss of points, loss of handicapping, and suspension, car parts, components, and/or equipment deemed as not in compliance with these rules. Any car part, component, and/or equipment which does not conform to specifications or tolerances contained in the 2016 rule book or is not otherwise approved by SMS may not be used in competition in 2016.

By engaging in competition at SMS, you hereby agree to have read the SMS 2016 General rulebook and the 2015 SK Light Modified rulebook.

SK Light Modified Mission Statement:
An open-wheeled Modified based upon the SK Modified® format integrating rigid cost controls. This division will provide a budgeted open-wheel racing opportunity for participants seeking to pursue an open-wheeled racing career.

DRIVER ELIGIBILITY – All drivers must have a NASCAR CHD (Charger Division Driver) or higher license. Drivers competing in the SK Light Modified division at SMS will not be permitted in the D.A.R.E. Stock, Limited Late Model, Late Model, or SK Modified® divisions on the same event date. Drivers must be minimum 15 years of age.

20E- 1.3 APPROVED COMPETITION MODELS- Approved model bodies are listed in the NASCAR Whelen Modified Tour (NWMT) Rulebook. Other models both domestic and foreign steel passenger cars may receive approval for the SK Light Modified division providing they are the same in body configuration and meet the spirit and intent of competitive racing in the SK Light Modified division.

20E- 2.2 OVERALL CAR WEIGHT– All specified weight requirements will include the driver and race gear. The minimum total weight for cars with the “A” engine package will be 2,630 poundsThe minimum total weight for cars with the “B” engine package will be 2,650 pounds. Maximum left side weight of all cars is 56% of total weight. Cars found under the minimum total weight rule after qualifying will be placed to last in that event. Cars found under the minimum total weight rule after the feature event will be penalized one (1) position per pound under.

20E- 2.3 ADDED CAR WEIGHT- Added weight must be in block form magnetic steel or lead only of no less than five (5) pound blocks (no pellets). Added weight must be securely bolted to the frame rail and painted white with the car number stenciled in black. No added weight will be permitted inside the driver’s compartment. Weight must be welded in a box or attached with two or more 7/16” diam. (minimum) grade 8 bolts and locking nuts.

20E- 2.4 CAR WEIGHTS AFTER RACE- Nothing may be added to or taken from the car to make total or left-side weight. Gas, oil or water may not be added. Wheels and tires cannot be changed, but an amount equal to one half of one percent (.5%) of the gross weight will be added for loss in weight due to race wear.

20E- 3.2.3 SIDE WINDOW GLASS/WINDOW NET – A nylon window net must be installed in the left side door window opening, and it must be positioned to cover the entire window opening. Window net should not be used beyond three (3) years from the date of manufacture. The window net must be rib type, made from minimum ¾ inch, maximum one (1) inch wide nylon material with a minimum one (1) inch and a maximum 2¼ inches square opening between the ribs. The minimum window net size must be must be 22 inches wide by 16 inches high. All window net mounts must be a minimum ½ inch diameter solid steel rod on the bottom and a minimum one (1) inch wide by 3/16 inch thick flat steel or a minimum ½ inch diameter solid steel rod on the top, with mounts welded to the roll cage. The window net, when in the closed position, must fit tight and be secured with a lever-type quick release latch acceptable to SMS Officials. The lever must be secured by a detent ball in the lever and may be supplemented by Velcro® fastener only – pins or clips will not be permitted. The latch must be mounted at the top in the front to roof bar (#3) release from the inside.

WINDSHIELD – A flat windshield is mandatory, per the NWMT rule book, made of a minimum of 1/8” polycarbonate that extends from the left A-pillar to the #4A center windshield bar and from the roof to the cowl. A minimum of three Dzus type fasteners must be used on each of the four sides. For additional specifications see the NWMT rule book.

20E- 3.2.5 REAR VIEW MIRROR- One (1) single image 8” x 2” rear view mirror mounted in the center of the upper windshield is permitted. If you use a head and neck restraint system, you may run a 14″ x 2″ mirror. A side view or spot mirror is permitted. Oversized mirrors maybe blacked out by the use of paint only, to obtain the correct size allowed.

20E- 3.5 DOORS – Door panels may be made of magnetic steel or aluminum. Aluminum crush panels must be installed per the NWMT rulebook. Aluminum crush panels must be installed per the 2016 NASCAR Whelen Modified Tour rules. For additional specifications see the NWMT rulebook.

20E- 3.6 QUARTER PANELS – All quarter panels may be made of aluminum or magnetic steel.

INTERIOR SHEET METAL – The rear center panel (over the fuel cell) must be made of magnetic sheet steel, 22 gauge, .031” thick, with a minimum width of 28”, and must extend from the rear vertical panel forward to the #7 roll bar, per the NWMT rulebook.

20E- 3.8  HOODS / ROOF-
C. All roof panels must be made of magnetic sheet steel, or be an SMS approved manufactured fiberglass roof panel. All cars utilizing an approved fiberglass roof must install the (minimum) 1/8” thick aluminum anti-intrusion plate in the roll cage halo as described in the following diagram.
For additional specifications on letters A. B. D. E. and F. see the NWMT rulebook.


20E- 3.11 IDENTIFICATION- All car number configuration and design is subject to approval by SMS Officials. Only single or double-digit numbers will be permitted. The size, color, and style of numbers must be adequate to permit prompt identification by SMS Officials at all times. Numbers must be solid color, at least 18 inches high, measured vertically, excluding borders and silhouettes, must be neatly attached to or painted on both sides of the car on the center of the door. Door numbers must be a minimum of four (4) inches in width, and slant no more than 30 degrees from vertical. The tops and bottoms of all numbers must be even (not staggered). Two (2) digit numbers must not overlap and must have a minimum of ¾ inch separation. A solid number 18 inches high, excluding borders and silhouettes, must be neatly attached to or painted on the roof, reading from the passenger side. A solid number a minimum of 12 inches high, excluding borders and silhouettes reading from the passenger side neatly attached to or painted at a 45 degree angle on the right front corner of the roof is also acceptable. Solid numbers, as large as possible, must be attached to or painted on the right outer nose and taillight covers. The use of number decals is acceptable if SMS Officials determine that the number is legible. Mirror foil numbers and decals will not be permitted. Paint schemes using a mirrored or holographic appearance will not be permitted.

Authorized SMS service centers for the GM Performance Factory Sealed Circle Track Crate Engines are:
R.A.D. Auto Machine             Ludlow MA                1-413-583-4414
T/A Engines                            Plainville, CT              1-860-747-6713

The GM part number 88958602 factory sealed circle track “602” crate engine is the only engine permitted. The motor may be purchased and delivered to one of our authorized SMS service centers, or you may purchase the engine through one of our authorized SMS service centers. This engine requires specific changes made to it to compete, and the work will be performed at the authorized SMS service center, then the engine will be resealed by SMS Officials. Any service work requiring the removal of any seal bolts must also be scheduled with, and approved by SMS Officials before the seal bolts are removed (see engine package “B” below). Tampering with seals will result in penalties and loss of eligibility of the engine to compete in the SK Light division. All engines must be sealed and documented to compete at SMS. All of the parts specified and/or that come stock OEM on these engines must remain as delivered, with no modifications or alterations of any kind. Engines may not be disassembled without being in need of repair. A maximum overbore of .030″ will be permitted. The maximum static compression ratio is 9.3 to 1. Please call our authorized SMS service centers or email the SMS technical staff at j3ams@comcast.net with any questions on these rules.

20E- 5-A CRATE ENGINE “A” REQUIREMENTS – Required internal changes to this factory sealed engine are: new valve springs, timing chain, and gears. The required external changes are a new harmonic balancer and oil pan. The “A” package engine is factory standard bore. The base price for this motor with the required changes is $5,800.

20E- 5-B CRATE ENGINE “B” REQUIREMENTS – Once you have disassembled the “A” engine package (for rebuild or repair), additional work is required to bring the engine up to the “B” specification. Please consult your authorized SMS service center for details and price (dependent on service required). .020″ up to .030″ overbore is permitted for the “B” package.

20E- 5.10-A CARBURETOR – Holley two-barrel model #4412 carburetor must be used. All parts must be a Holley manufactured part for the 4412 model. Polishing, grinding, resizing or reshaping of any part or orifice is not permitted. The body, base plate, metering block, and bowl must be a standard Holley 4412 part, HP parts are not permitted. OEM type gaskets, jets and power valve must be used.

The diameter of every hole in carburetor must pass the standard NASCAR /SMS pin and tooling gauges as part of our routine tech process.
(1) Body of carburetor and metering block: No polishing, grinding or reshaping of any part. Drilling of additional holes or plugging holes is not permitted.
(2) The choke may be removed, but all screw holes must be permanently sealed.
(3) Choke Horn: Choke horn may not be removed.
(4) Boosters: Boosters may not be changed. Size or shape must not be altered. Height must remain standard.
(5) Venturi: Venturi area must not be altered in any manner. Casting ring must not be removed.
(6) Alterations to allow additional air to be picked up below the opening of the venturi such as altered gaskets, base plates and drilling holes into the carburetor will not be permitted.
(7) Base Plate: Base plate must not be altered in shape or size.
(8) Butterflies: The stock Holley 4412 or Stainless Steel Holly part #346 butterflies must be used. They may not be thinned or tapered. The Butterflies must remain as manufactured, and must maintain the Holley production tolerance thickness of .0438” to .0398”.  Idle holes may be drilled in butterflies. Screw ends may be cut even with shaft but screw heads must remain standard. (9) Throttle Shaft: Shaft must remain standard and must not be thinned or cut in any manner.

20E- 5.10.4 CARBURETOR ADAPTER – Big Haus U.S.A. #001 aluminum adapter plate must be used. Alterations of any kind to the adapter plate are not permitted.

Only a round dry type paper air filters elements maintaining a minimum 12 inches and maximum 14 inches diameter is permitted. The air filter element must be a minimum of 1-1/2 inches, maximum five (5) inches in height. All air must be filtered through the element.
B. Only a round, magnetic steel or aluminum filter housing is permitted. The top and bottom of the air filter housing must be solid with no holes. A maximum of one (1) inch lip will be permitted from the air filter element to the outer edge of the air filter-housing top and bottom. The air filter-housing carburetor mounting ring must have only one (1) round hole a minimum of five (5) inches in diameter. It is permissible to attach a shield to the front area of the air filter housing up to a maximum of one half of the air filter circumference. The shield must not be higher than the height of the air filter element. The air filter housing top and bottom must be the same diameter. The air filter housing must be centered and sit level on the carburetor. No air induction, ducts, baffles, tubes, funnels or anything else which may control the air entering inside of, or between the air filter and carburetor is permitted.
C. The bottom of the air filter element must measure within one (1) inch of the carburetor’s top flange. A spacer may be used between the carburetor and the air cleaner so long as the one (1) inch specification is not exceeded.
. No portion of the hood may be higher than the bottom of the air cleaner.

20E- 6.1 IGNITION SYSTEM- NASCAR approved ignition system must be used.
A. Electronic distributors are permitted. All electronic distributors must be in stock type housings, have stock type controls and modules, be equipped with a magnetic pickup, be gear driven, and be mounted in the stock location. Billet distributor housings are permitted.
B. Single or dual point camshaft driven distributors are permitted.
C. Only one (1) ignition coil is permitted and must be mounted on engine side of the firewall.
D. Electronic firing module amplifier box is not permitted.
E. Computerized, multi-coil, dual electronic firing module box or crank trigger systems are not permitted. Magnetos are not permitted. All ignition systems are subject to approval by SMS Officials.
F. Adjustable timing controls are not permitted.
G. Retard or ignition delay devices are not be permitted.
H. A MSD # 8728 External RPM limiter with a 6000-RPM chip is mandatory. The violet wire of the MSD # 8728 must be cut back flush to the units housing. The green and the white wires of the MSD # 8728 must run directly to the coil negative. As an option, a MSD #8727CT digital RPM limiter set at 6000-RPM may be used. The MSD # 8728 or the #8727CT must be mounted on the engine side of the firewall in plane view. SMS Officials may require on the #8728 a replacement of the 6000-RPM chip with an SMS supplied chip at any time during an event. RPM limiters must be fully functional and operational at all times.
I. Accessories to regulate the power supply are not permitted.
J. The tachometer wire must run from the distributor to the tachometer along the #8 dash bar separate from any other wires and in unobstructed view for inspection. The tachometer wire must be isolated from any other wires, connections or devices. The entire length of the tachometer wire must be visible from distributor to the gauge.
K. The vacuum advance unit may be replaced with a manual non-electronic timing adjuster that does not extend more than two inches beyond the distributor housing.

20E – 6.3 ALTERNATOR- A functioning 12-volt single alternator system with an internal voltage regulator and one (1) output wire must be used. External voltage regulators are not permitted. The alternator must be mounted on the front of the engine. Only standard production V-type or flat type V-ribbed alternator drive belts will be permitted. 

20E- 6.5 BATTERY – One (1) 12-volt Gel or Glass Mat type battery with a minimum weight of 17lbs. is mandatory. The battery must be located between the frame rails under the hood or the floor of the car. If located under the floor, the battery must be completely encased, if located under the hood the battery must have a suitable cover. The battery must not be forward of the radiator or rear of the rear end housing of the car. The battery location must be acceptable to SMS Officials.

20E- 6.7.1 RADIOS- Monitoring of SMS Race Control on Frequency 461.13750 is mandatory via a Raceceiver, Microscanner, or Receiver. The approved one-way receiver must be mounted in plain view for inspection on the back of the driver seat. Any car not monitoring the Race Control frequency during practice will be black-flagged to be made aware of their failure and is required to remedy it before proceeding further in the event.

Track Frequency Channel SK Light – 461.13750

20E- 6.7.3 TRANSPONDERS- Transponders are required on the cars at all times. See SMS General Rules section for locating transponders properly. Any car not registering a transponder signal during practice will be black-flagged to be made aware of their scoring transponder’s failure and is required to remedy it before proceeding further in the event.

32 Highlands Parkway
Suite 104
Smyrna, GA 30082
Tel 678-816-4000
Fax 678-816-4001

20E- 7 ENGINE COOLING SYSTEM- Only water or SMS approved coolants or additives may be used in the cooling systems.

20E- 7.1 WATER PUMP- Steel or aluminum OEM type mechanical pump must be used. Combination water pump/alternator units are not permitted.  Any serpentine, cog or V-belt pulley system is permitted.

20E- 8 ENGINE OIL SPECIFICATIONS- Combustion enhancing oils or additives are not permitted.

The following part numbers are the only headers permitted. All headers must remain unaltered and exactly match the SMS factory sample headers. Troyer Chassis – Kooks # SMS1033 or Flowrite #SMS 25 Raceworks Chassis – Kooks # SMS1033 or Flowrite #SMS 45 Chassis Dynamics Chassis – Kooks # SMS1435 or Flowrite #SMS 35 SPAFCO Chassis – Flowrite #SMS 55
B. The exhaust header flange must mount directly to the cylinder head with no spacers between the flange and the cylinder head. A maximum header flange thickness of ½ inch is permitted.
C. Inserts are not permitted in any part of the header or collector. Merge, crossover and pyramid collectors are not permitted.
D. Exhaust pipes must come out of engine at cowl and must extend a minimum of six (6) inches past the cowl. Right exhaust pipe may run beneath the car, but must turn down and out toward the bottom of the right side frame rail.
E. LOBAK # RCM 30-12-30, LOBAK #35-12-35, Kooks #R300-10, or Flowrite P/N FR300 mufflers are required at all times. Modifications or repairs of any type are not permitted on the muffler. Both muffler flanges must be intact. Mufflers must be removable for inspection.
F. Thermal wrap is not permitted anywhere on exhaust system.
G. Only one muffler and exhaust pipe allowed per side.
H. Exhaust system subject to approval by SMS Officials.
I. Interior coatings are not permitted.
J. Exterior coatings other than paint are not permitted. All other coatings including powder coatings are not permitted.

NOTE: The life expectancy for all Lobak mufflers is two years. Each team is responsible for inspecting their mufflers to insure they are not illegal due to wear. A muffler will be deemed illegal if it is missing one or more of the internal baffles.

20E- 10 ENGINE DRIVE TRAIN – FLYWHEEL AND CLUTCH- Stock OEM dimension steel flywheel for engine type. OEM type steel pressure plate and steel disc only. Solid type disc only, no paddle or button type discs. Minimum diameter 10″ clutch and pressure plate. Drilling or lightening of any part is not permitted. Steel bolts only. Flat surface machining allowed only on the face of the flywheel, any cutting on the backside of the flywheel is illegal. The following weights are the minimum allowed for each part: Flywheel only (no bolts) 14.5 LBS. Pressure plate, Cover, & Solid Disc 16 LBS. The steel solid disc (no bolts) must maintain a minimum weight of 2.5 pounds and a maximum weight of 3.8 pounds after the combined weight has been determined.

20E- 10.3 BELL HOUSING – Only a commercially manufactured magnetic steel bell housing may be used. The bell housing must enclose the flywheel 360 degrees with minimum 3/16” inch magnetic steel. Any modifications you make to the bell housing must be done with 3/16” steel and welded in place (no bolt on pieces). A Commercially manufactured bell housing (like the Quarter Master # 008110440) with a bolt on bottom cover may be used. An opening no larger than 3 ½ x 4 inches may be used for throw out bearing access. This hole may be covered with sheet metal.

. Only OEM production stock 3 & 4 speed transmissions will be permitted. Top loader transmissions are not permitted. Gear ratio must be of stock OEM production.
B. Only stock O.E.M. factory housings will be permitted.
C. Only OEM type, steel, angle cut forward gears are permitted. Square cut forward gears are not permitted.
D. Removal of first gear or replacement of first gear with a metal spacer, in 4-speed transmissions is permitted. All other forward and reverse gears must be in working order, and they must be operational from inside the driver’s compartment. All transmissions must have a constant engagement of the input shaft with gear and countershaft with cluster gears.
E. Five-speed transmissions, with gears removed are not permitted.
F. Quick change transmissions are not permitted.
G. Automatic or semi-automatic transmissions are not permitted.
H. Machining or lightening of any internal rotating or non-rotating parts including gears, shafts and case is not permitted. Gun drilled transmission shafts are not be permitted. Welding on any internal part is not permitted.
I. Additional or different from OEM bearings other than the tail-shaft, which may have roller bearings, is not permitted.
J. Auxiliary, over or under drive transmissions are not permitted. High gear must have a ratio of 1 to 1 and no other gear may have a ratio higher than 1.20 to 1. The shifter and all of its components must be made of steel or aluminum.

20E- 10.6 REAR AXLE
B. Full floating magnetic steel double splined rear axles must be used.

B-1. All axles must be a minimum of 7.00 pounds while still maintaining a 1.250-inch manufactured outside shank size and a .6875-inch inside hole diameter.
E. Only magnetic steel axles, bearings, and axle housings are permitted. 
F. Only one-piece, magnetic steel axles will be permitted. The axle splines must be straight cut, not crowned.
Crown type axle splines will not be permitted.
G. Cambered rear axle housings or other cambered components will not be permitted. A tolerance of 1½ degrees of camber (positive or negative) will be permitted.
Only aluminum or steel drive plates, the same thickness on the left and right side will be permitted. The drive flange splines must be straight cut, not crowned.
Only ten (10) inch ring gear and housings are permitted.

M. Thermal dispersant coatings are not permitted.

GEAR RULE – 4.12 Maximum for straight rears, 4.26 Maximum for Quick Change rears. Rear ends and components will be weighed as part of post race tech.

20E- 10.8 TIRES – Hoosier Tire East of Manchester Connecticut will be the sole supplier of tires for the SK Modified® and SK Light Modified Divisions. The size and compound numbers are 26.0/13.0-15 M30 on the left side and 27.0/13-15 M45 on the right side. Tire purchases prior to the first scheduled race of the season may be made at Hoosier Tire East. After the first event of the season all tires used at SMS must be purchased at the track on race day. Each tire will carry a special bar coded serial number. The legibility of the bar code is the sole responsibility of the team. This number will be scanned and entered into a database designating it as a tire for use at SMS. Each scanned serial number will be placed on a Tire Inventory that will be assigned to the driver that the tires have been purchased for. In the event a driver changes cars for qualifying or feature racing, his tire inventory must accompany him to the new car. Each driver must update and return a Tire Inventory Card to the SMS Tire Delegate. For the first race of the season, SK Light Modified drivers will be allowed a maximum of eight (8) tires in their inventory. For each completed event (EIRI) attended an SK Light Modified driver will be issued one (1) tire credit for use at any future event as follows: Taking the green flag in the feature will allow a driver to receive one tire credit. These tire credits may be accumulated and used at any future race event. The amount of extra tires allowed for longer distance feature events will be determined by SMS Officials. After a designated number of weeks into the season and at the discretion of SMS Officials, any new driver will only be allowed to start their season off with four (4) new tires and two used ones (total of 6 inventoried tires). The maximum number of tires allowed in a driver’s race inventory throughout the season will be twelve (12) for the SK Light division. Once a driver’s inventory has filled up to 12 tires, that driver must begin to manage their inventory by replacing used/junk/scrap tires. Tires that you throw away must have their barcode number designated as such. Please notify the SMS Tire Official of any tires you discard and will not use. SMS Officials may change or amend this rule at any time. If a tire cannot be identified, it will be considered illegal. SMS Officials may confiscate and/or impound tires at any time for inspection. The JTR Eagle PPM Tester will be set at a fixed level and will be strictly enforced throughout the 2015 season.

20E- 10.8.1 PHYSICAL REQUIREMENTS E. Minimum circumference of the right rear tire@ 20 psi. is 84″. F. Minimum tire pressures for all inspection purposes are ten (10) psi for both left side tires and fifteen (15) psi for both right side tires. Air may be added to the tires to achieve only the minimum tire pressures during inspections, per an SMS provided tire pressure gauge.

NOTICE: A participant competing in any race at SMS specifically agrees that he/she acknowledges it is illegal to soak or treat racing tires and that said soaking or treatment of racing tires is against EPA regulations and further contains carcinogens and hazardous material which are unfit for his/her health and the health of all competitors and spectators. Any participant found violating the rule is subject to suspension.

The SK Light Modified division must utilize the track specified shocks only. Shocks are subject to dyno verification and must be within the manufacture’s tolerance limits for each part number. Shocks must remain as manufactured with no alterations of any kind.
B. The SK Light Modified track approved shocks are: Pro Shocks # TA55½B Front Pro Shocks # TA74½B Rear

Front spindles must be linked to frame utilizing two individual tethers per spindle. All tethers and their installation must be acceptable to SMS Officials. Low drag components (excluding seals) are not permitted. The use of oil filled hubs, oiled bearings, low friction bearings, non-steel bearings, coated or polished spindles, bearings or races will not be permitted. Two standard steel wheel bearings, a wheel bearing seal, a torque nut and a standard nut locking mechanism are the only components permitted on each spindle/hub assembly.
Oil filling of any spindles, wheel bearings or hubs is not permitted.

20E- 12.8.2 GROUND CLEARANCE REQUIREMENTS- The frame rail and sheet metal ground clearance is a minimum of two (2) inches. All ground clearance requirements are measured with the driver in the car. Frame heights will no longer be checked at the conclusion of feature events.

Four wheel disc brakes are mandatory. Only magnetic cast iron or cast steel round circular rotors permitted. Only metal brake calipers will be permitted. Drilled, slotted or grooved rotors are not permitted. Only factory dust cleanouts are permitted. Dust cleanouts should not exceed .038 in depth. If the dust cleanout exceeds .038 in depth, the rotor will be deemed illegal. The brake rotors must be bolted to the hubs. Floating brake rotors will not be permitted.
B. Only single stage master cylinders are permitted.
J. Brake calipers with a maximum of four (4) pistons are permitted. Each brake caliper’s pistons must all be of equal size. Each brake caliper may not exceed a racer net price of $265.00
K. All rotors and brake components subject to SMS Officials approval.

20E- 14.2 – BRAKE COOLING- Electric blowers are not permitted for cooling purposes in brake duct systems. Additionally electric blowers are not permitted anywhere on the car for cooling (i.e. brakes, rear end, etc.).

20E- 15 FUEL SPECIFICATIONS A. The fuels listed below are permitted for use in the SK Light Modified division. Any blending of fuels or use of any additives is not permitted.

Brand Name                Grade of Fuel
Sunoco Race Fuel       260GTX

This fuel is available for purchase at SMS. Several testing procedures will be utilized to insure that all racers use of the approved fuel. Fuel samples taken must exactly match all of the manufacturer’s printed specifications, or penalties may result.
B. Icing or cooling of the fuel system is not permitted in the garage, pit or racing area.
C Gasoline may be tested and certified at any event through the application of various chemical analyses as considered appropriate by officials. Gasoline may be checked before, during and after racing events.
D. Nothing may be placed in the fuel line except a standard fuel filter. The use of any type of fuel catalyst or other fuel-altering device is prohibited.

20E- 16 FUEL SYSTEM – See NWMT rule book

20E- 16.1 FUEL CELL- Must meet NASCAR specifications with a fuel cell bladder made of a material that returns to its original size and shape after deformation. Rotational molded bladders are not permitted. It is highly recommended that the fuel cell bladder be no more than six (6) years old. Competitor must provide bladder model, serial number and date(s) to SMS Officials before competing. If a gas cap is used it must be painted white with the car number on it for identification. For additional specifications see the NASCAR Rulebook. The minimum requirement for approved fuel cells at SMS are as follows: ATL Super Cell “100” FB1 – Series Bladders. (Note: the complete cell will be the SU1- Series), and the Fuel Safe Sportsman Cell (SM Series). Any cell that is rated above these cells (ATL 200 & 500 series), and the Fuel Safe Pro Cell (PC Series), will also be approved for competition at SMS.



20E- 16.20E- 16.3 FUEL CELL / CONTAINER INSTALLATION 5.3 FUEL SHUT-OFF- A 1/4-turn fuel shut-off valve of minimum 3/8-inch NPT with minimum 4-inch handle is required in the fuel line. The fuel shut-off valve must be located 8-inches inboard of the passenger side frame rail’s outside edge and 24-inches forward of the main roll bar (#1 bar). The fuel shut-off valve must be mounted securely to the underside of the driver’s compartment sheet metal. The fuel shut-off valve shank must protrude through a maximum 1-inch diameter hole in the sheet metal to the interior of the driver’s compartment. The fuel shut-off valve handle must be parallel with the sheet metal that the valve is mounted to. The fuel shut-off valve handle must be a minimum of 4-inches in length, red in color with a minimum of 1-inch clearance from the sheet metal throughout its full travel. A minimum 6-inch by 6-inch square area must be painted white with the fuel shut-off valve’s ON and OFF positions clearly labeled with 1/2-inch tall, black in color lettering. The shut-off valve must rotate clockwise from a ON position with the handle parallel with the frame rail, pointing towards the rear of the car, to the OFF position with the handle perpendicular to the frame rail pointing toward the driver.

20E – 18 ROLL BARS (8) (A) The door bars (#9 A & B), on both the left and right sides, must have a minimum of four (4) bars equally spaced from top to bottom that must be welded horizontally between the vertical uprights of the main roll bar (#1) and the front roll bar legs (#2 A & B). The top door bar on each side must maintain a minimum vertical height of 15-1/2 inches from the top of the main frame rails to its centerline and match up with the intersection of the dash panel bar (#8) at the roll bar legs (#2A & #2B) at the front and the intersection of the horizontal shoulder bar (#7) at the main roll bar (#1) at the rear. All door bars must be convex in shape. The door bars (#9 A & B) must have a minimum of six (6) vertical supports per side with two (2) equally spaced between each door bar. These supports must be made from a minimum of 1-3/4 inches by 0.090 inch wall thickness magnetic steel seamless round tubing (not numbered but shown in the left side view of diagram #3). Right side door bars must cover a minimum of 25 inches of door length and may be either four (4) horizontal bars with six (6) vertical studs or two (2) horizontal bars and two (2) bars configured in an X design. If the X design is used, a vertical bar must connect through the center of the X from the top horizontal bar to the frame.

(B) A 13-gage (0.0897 inch thick) magnetic steel anti-intrusion plate(s) must be securely welded to the outside of the left side door bars. The anti-intrusion plate(s) must fill the area between the horizontal centerlines of the top and bottom door bars, and vertical centerlines of main roll bar (#1), and the left front roll bar leg (#2A). The plate(s) must be formed to match the curvature of the door bars. Plate(s) welded between the vertical upright bars should be as large as possible. All plate(s) must have the corners welded with one (1) inch of weld followed by a maximum of three (3) inches of surface not welded and followed again by a minimum one (1) inch weld. To facilitate emergency removal of the left side door bars (#9A), the anti-intrusion plate must have six (6), 2-1/8 inch diameter holes cut in the anti-intrusion plate, with three (3) holes forward of the front vertical supports and three (3) holes rearward of the rear vertical supports in the following locations: The upper two (2) holes must be centered vertically between the left side door bars (#9A-1&2), at an on-center distance of three (3) inches from the center of the front vertical support and the rear vertical support. The middle two (2) holes must be centered vertically between the left side door bars (#9A-2&3), at an on-center distance of three (3) inches from the center of the front vertical support and the rear vertical support. The lower two (2) holes must be centered vertically between the left side door bars (#9A-3&4), at an on-center distance of three (3) inches from the center of the front vertical support and the rear vertical support (see Diagram #9A BELOW).

(9) All cars must have a foot protection bar acceptable to SMS Officials installed on the left side of the roll cage. The foot protection bar must be located at or in front of the pedal assembly, when viewed from the side and above. The foot protection bar must be completely welded to the left front roll bar leg (#2A) and extend forward and be completely welded to the main frame rail or front sub-frame.

NOTICE – Competitors are solely and directly responsible for the safely of their race cars and racing equipment and are obligated to perform their duties (whether as a car owner driver or crew members) in a manner designed to minimize to the degree possible the risk of injury to themselves and others.

CONTINGENCIES- Contingency Sponsors are a valuable part of the SMS program. Contingency stickers must be displayed for either product or monetary consideration. Each division will be notified as to what stickers are required to be eligible for contingency rewards. In particular, the decals must be mounted on the driver’s side of the car in such a manner that they are clearly visible in a photograph.

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