2015 SPORTSMAN MODIFIED RULES
These rules are posted here as conveyance only, Not responsible for any type Os or other copying mistakes.
Call the track office at 607-657-8222 or ask at the track for a official printed copy.
SPORTSMAN MODIFIED STYLE BODY
ALL MEASUREMENTS WILL BE TAKEN WITH OR WITHOUT DRIVER OR FUEL.
BODY MATERIAL ALLOWED
Only aluminum or steel will be allowed for all inner and outter body panels. The roof must be fiberglass only.
Hood, hood scoop, windshield cowl, right rear inside tire clearance cover and front spoiler may be constructed or either fiberglass or aluminum. Only clear lexan will be allowed for the rear spoiler and the rear wing windows.
Roof must be covered from side to side on roll cage and also be centered on frame, no offset bodies. Leading edge of roof must be fastened in a stationary position a minimum of 33" and a maximum of 48" in front of rear axle centerline. The roof must be securely fastened at the back and on both ends. Length of roof will be a maximum
60", minimum 48". Width of roof will be maximum 52" and a minimum of 48". Must display a turtleback style and shape. No flat roofs. Overall height will be minimum 52' and a maximum 61", measured from the ground. All roofs must be one piece fiberglass only. No carbon fiber. Rollbars must be exposed from any angle. No vertical metal used to mount roofs will be allowed covering roll bars. Roof must weigh at least ten pounds.
FRONT DOOR POSTS
Door posts must be 2" wide from the side view from the roof all the way down to the door. The posts must be flat, no angle shape or round tubing will be allowed. No lexan vent windows or excessive sheet metal will be allowed in the vent corner where the post meets the door panel.
REAR WING WINDOWS
All window styles must be clear, smooth lexan with no bends or breaks. No writing or decals allowed on the wing windows. Rear view of the wing window must go in a straight line from top of quarter panel or body line to the roof with a maximum gradual deflection of 2" in the center of wing window. Side view of the rear wing window must extend from the roof to the rear top of quarter panel in a straight line or in accordance with the window style chosen. A maximum of 3" higher than the rear deck height at that point will be allowed.
BODY WIDTH AND GROUND CLEARANCE
Body width, measured anywhere along the body line, front or back: 68" maximum, 64" minimum. Minimum body and chassis ground clearance 2 1/2". No fan or ground effects cars. No rubber skirts, fins, or spoilers are
permitted under car,
Side door panel: minimum 60", maximum 70" in front of centerline of the rear axle. Doors must be straight up and down within that measurement. Front door extensions will be allowed up to 20" behind the front axle centerline.
"Front door height must be a maximum of 38" and minimum of 30" from the ground measured at 60" from rear
axle centerline. Ground clearance on the bottom of the doors must be a minimum of 6" and a maximum of 12" from the ground. All doors and rear quarter panels may have a maximum lip of 1 1/2" rounded at 90 degrees and facing inward only, on the top and the bottom.
REAR QUARTER PANELS
Rear quarter panels must match each other. They must be a maximum of 45" and a minimum of 40" from the ground at the rear and continue in a straight line with top of door. You may use a fender flare, up to a maximum
of 2" from the body but overall body width must still be maintained at a 68" maximum. Rear quarter panels can extend back to 48" maximum at top and may incline down to 44" maximum at bottom measured from center of rear axle to rear of car. Ground clearance on rear quarter panels must be a minimum of 8" and a maximum of 16".
The rear spoiler must be clear lexan with a maximum height of 5" from the rear deck and must not have any writing or stickers on it. The rear spoiler must be non-adjustible with no hinges or slides. A maximum of three vertical supports may be used to fasten the spoiler to the rear deck. These supports may not exceed 2" in vertical height and 10" in length.
Must be a maximum height of 45" and minimum of 40" from the ground. Rear deck lid or trunk lid must be fully enclosed from quarter panel to quarter panel and have a minimum height of 9" and a maximum of 14" in vertical coverage behind the fuel tank. Left and right rear trunk lids must be symmetrical in size and shape and show no specific bulge or extension to cover fuel filler hose or apparatus within the 9" to 14" of vertical coverage. This panel must completely cover the fuel cell, filler hoses, and vent lines. The fuel tank must be completely enclosed from the bottom of this panel to the bottom of the fuel cell. The fuel cell must also have both sides completely covered by sheet metal in addition to the container it is enclosed in. Within these dimensions there can be no openings. No openings from top of fuel cell to bottom of trunk lid are permitted. Any vent line nozzle used for catch can purposes must be mounted on the left side quarter panel only. No crew member will be permitted behind the car during pit stop refueling.
HOOD, NOSE, AND FRONT SPOILER
The hood, nose, and front spoiler can be no wider than 36" and no narrower than 24". Shock covers or deflecters may not be part of or riveted to the nose or spoiler exceeding the 36" width maximum, fabric shock covers are allowed as long as they are used for the prevention of dirt getting at shock piston and not used for any aerodynamic advantage. The front spoiler may not extend any more than 20" in front of the front axle centerline. T'ne front spoiler must be non adjustable, no hinges or sliders. Hood shall be considered from the front roll cage to on top and even with the front of the radiator. Nose piece shall start from where hood ends to a maximum of 20"
in front of front axle centerline. They all may have 2" maximum lips up or down on both sides following the
contour of the body. The hood, nose, and spoiler may not overlap each other's location on the frame. Any part of the hood may not exceed 10 degrees nor can sheet metal have an opening or extrusion between the hood and nose. Hood must extend over the radiator and have complete sides.
Front windshield opening: for the optional ram air style scoop, a 10" vertical measurement from lowest point of
roof or roll cage to highest point on hood, including the hood scoop. is required. For the conventional type scoop a 8" vertical measurement will be required.
An optional hood scoop mounted on top of the hood for the purpose of enclosing the carburetor or ram will be allowed providing they meet specifications. Both style scoops may use fiberglass. The option of keeping the hood fully enclosed will also be allowed.
Ram air type scoop: Maximum length is 30" measured from rear motor plate to front of hood scoop.
Maximum width 18". The front vertical opening of the scoop can be a maximum of 6" at the beginning of the scoop only, The overall height of this scoop must maintain a minimum of 10" of vertical vision for the driver. The measurement will be taken from a horizontal line from the highest point of the hood scoop to the lowest point of the front roll cage and or roof. Hood scoop must be fastened to the hood and completely enclose the carburetor and air filter. A tolerance of 1/2" will be allowed on all these dimensions.
Conventional no ram air scoop: a maximum of 25" is allowed from center of the carburetor forward. The width allowed is a maximum of 22". The height must maintain a minimum of 8" of vertical vision from the top of the scoop to the lowest point under roof or roll cage.
INTERIOR SHEET METAL
Any horizontal body support, other than the inner pods, whether in front or rear must be a maximum of I" deep
by I" thick tubing or flat stock only. No inside or outside wings, spoilers, air foils or wind deflectors are allowed. No double panels will be allowed that creates a wing effect. A I" maximum reinforced lip will be allowed on all lexan, but all allowable measurements must still be maintained. All inner sheet metal used must completely cover areas from door to door, quarter panel to quarter panel. No holes or openings are allowed in this area. No vertical fins, air dams, or farings allowed on the sides or behind the roll cage. Sheet metal must be flat single plane across the inside of the car. No covered roll bars for aerodynamic purposes are allowed. Sheet metal that is one piece and part of a body panel bent around tubing, for purposes of protecting the driver or finishing off panel, is not considered an aerdynamic advantage provided it is not to excess. No louvers or holes in the interior or exterior sheet metal are permitted with the exception being the cooling of the radiator, engine, and oil cooler. The floor
pan or underpan may not be any wider than the frame, from front to back, and may not have any lips or fins
Numbers must be distinguishable. Limited to three digits, two shall be primary numbers. Numbers are required on roof, nose, rear deck and both doors. Numbers shall be a minimum of 18" high on the roof and doors, and 8" high for the rear deck and nose. Do not let nerf bars block scorer's visibility.
SPORTSMAN CHASSIS SPECIFICATION
1. Only 2X4 box frames are permitted between axle centers, front and rear. The 4" side must be vertical. Frame rails must be steel only. All 2 X 4 rails must be .120" wall thickness only. A 3/16 hole may be drilled in frame rail
to check for thickness. No other holes are allowed. All tubing allowed for the frame rails must either be 1 1/2" diameter x .095" wall or 1 3/4" x .095" wall.
2. Frame width shall be as follows: Front at shock towers: 24" minimum, 35" maximum. Rear: 26" minimum, 35" maximum. The minimum frame width at the rear roll bar must be 26". All measurements are to be taken from the outside of the frame rails. All measurements shall be taken at both top and bottom of frame at its longest length. Clips, sub-frames, etc. are considered part of the frame.
3. Minimum length of the 2 X 4 frame rails must start at 14" in front of rear axle centerline and extend to the front of the radiator. All kick up material must be same specifications as the roll cage or frame material. Left and right frame rails, both top and bottom rails, must be equidistant from the driveline centerline in a vertical plane along the total length of frame.
4. Titanium or carbon fiber materials are not allowed on the chassis.
1. Only round steel roll over bars may be used. Front and rear roll bars must be connected at top in a cage type configuration. Two round horizontal side bars on each side are mandatory. The top side bar must be a maximum
of 20" below the top roll bar. Proper bracing and triangulation on front and rear roll bars is required. It is recommended that all roll bar bracing be a minimum of 1 1/2" diameter by .095" wall thickness, A minimum of
one diagonal bar across the top of the roll cage is mandatory.
2. The rear main roll bar hoop must be a minimum of 26" measured across from outside to outside of tubing and must maintain that measurement from the bottom all the way to the top of the cage. Bottom of the rear roll bar must be welded to the 2 x 4 frame (No outriggers). The front roll bar must be measured and constructed the same way, except that the allowable taper in the frame rules will govern the width dimension.
3. Only two roll bar diameters will be allowed. Roll bars of 1 3/4" diameter will require a minimum of .095" wall thickness. Roll bars of 1 1/2" diameter will require .120" wall thickness.
Seat and steering wheel must be centered in the frame. The seat must be a maximum of 16" from the center of the rear end to back of seat bottom. A high back seat made completely from aluminum is mandatory. No fiberglass or carbon fiber materials are permitted.
Only one radiator allowed and it must be centered squarely, not angled, in front of the motor in a vertical position. No plastic or carbon fiber allowed. No auxiliary cooling tanks or catch cans allowed in driver's compartment.
The engine must be centered in the chassis and placed in an upright position. Engine set back: minimum 56", maximum 66" with 112" absolute maximum tolerance. Set back will be measured from the center of the front axle to the rear machined bell housing surface of the engine. No rear engine cars allowed.
Approved North American manufactured manual shift transmission only, no automatics. No overdrive or
under drive transmissions allowed. No running through reduction gears, transmission must be direct drive to rear end at racing speed. Transmission must have forward, neutral, and reverse gear in good working condition. From a neutral position with the motor running, a car must be able to go forward and backward in a smooth manner. Transmission must bolt to the bellhousing. Car must have a battery and a self starter in working condition. The car must start and move under Its own power.
No chassis, driveline or suspension components made of carbon fiber allowed. Only two u-joints per driveline. A drive line shield is mandatory.
Competition rears only. No hyphoid type rears allowed. No limited slip type rear ends or hubs are allowed. No lockers or two speed rears are allowed. Rear end must have solid aluminum or steel spool only, Rear spindles may be steel or aluminum only. If aluminum it must be a one piece tube and spindle with a minimum outside diameter of 2 7/8" and maximum inside diameter of 2 1/2". Live rear ends with aluminum or steel axles are allowed, The rear end or chassis must not be offset any more than 4" from center of the inside tire width, measured from the inside of the left rear tire to the inside of the right rear tire, at axle height. Must use conventional type quick change rear end only. Axles on closed rear must be steel only.
The front axle must be straight, one piece steel tubing only with no camber adjustments. No split axle or dropped axle allowed. All brackets on front the axle must be bolted or welded, no bird cages or slides. Modified type front spindles only. It is recommended that bearing shafts be made of steel. Chassis may not be offset any more than 4" from center of inside tire width, measured from the inside of the left front tire to the inside of the right front tire at axle height. Front wheels must be fully exposed. No fenders are allowed.
CHASSIS GROUND CLEARANCE
There must be a minimum of 2 1/2" ground clearance from the chassis or anything attached to it, including any part of the body. No metal, lexan, or rubber air dams, fins, spoilers, or skirts are permitted under the car. No ground effects car.
No independent suspensions front or rear, No "A" frames or ball joints may be utilized for steering axis, kingpin only. No four wheel steering allowed that Is actuated by steering wheel. All suspension systems must be mechanical with no form of electrical, radio, or computer assistance. No form of traction control is permitted. No weight jackers or panhard rod adjusters which can be adjusted from the cockpit allowed. Cantilever suspensions and inboard shocks are not allowed. No sway bar adjustments that increase wheel weights from the cockpit, Sway bar quick disconnects are allowed.
Any form will be allowed (torsion bars, coil overs, leaf springs, etc) providing they are made from steel, No carbon fiber or titanium are allowed.
Only one shock per wheel. No titanium. No shocks that can be adjusted from the cockpit will be allowed.
All cars must have four wheel hydraulic brakes in good working order. No carbon fiber or no aluminum rotors and pads. On live rear axles, one Inboard and one outboard brake assembly is allowed.
Must be made from round steel tubing only, with a minimum diameter of 1 1/4" by .095" wall thickness for main bumper and all bracing. It must consist of two rails, an upper and lower. These rails must have four sockets or supports attached to the frame. The four tubes that support the bumper from the four frame sockets must be horizontal. These rails must also be a minimum of 6" apart and a maximum of 12" measured from top to bottom and maintain that measurement for a minimum width of 24" or a maximum width of 30". It must also have an
18" center measured from the ground up to the middle of the bumper. The front bumper may not extend more than 24" in front of front axle center centerline. No V-shaped bumpers, crash area must be flat and vertical for the full width of bumper. Bumper must have no sharp edges.
Must be made of round steel tubing only, with a maximum diameter of 1 1/2" by .095' wall thickness for main bumper and all bracing. It must consist of two rails, an upper and a lower, which must have four sockets and horizontal support bars attaching it to the frame, These rails must also be a minimum of 10' apart and a maximum of 16" measured from top to bottom and maintain that measurement for a minimum width of 64" or a maximum width of 86". The rear bumper or any side bars cannot extend past the outside of tire sidewalls on both sides. It also must have an 18" center measured from the ground up to middle of bumper. The rear bumper may not exceed 52" In back of rear axle centerline. No V-shaped bumpers, crash area must be flat and vertical for the full width of bumper. Bumper must have no sharp edges.
Must be made of round steel tubing only, with a minimum diameter of 1 1/2" by .095" wall thickness. All bracing must also be a minimum of 1 1/2" outside diameter by .095" wall thickness, Maximum wall thickness must be .095" with no solid bars or ballast added Inside. Rub rails must be outside of body panels but may not exceed the outside edge of the tires. The exception is the left rub rail only, which may extend an absolute maximum of 2' outside the left rear tire sidewall. Rub rails must be rounded with no sharp edges and bent at a gradual 90 degrees and must protrude a minimum of 6' back in past the body. Rub rails must be a minimum of 50"iong, end to end. Single bar rub rails only.
One fuel tank with a maximum of 22 gallon is mandatory, used for gasoline only. Fuel tank height will be 12' minimum from the ground to the bottom of the tank. Tank must be centered Inside of the frame rails and be rectangular or square in shape on all sides for measuring capacity. Fuel tank must be fully encased in a steel container with a minimum thickness of 20 gauge. An optional aluminum container may be used with a minimum thickness of .060". Fuel tank must be fully foamed with a minimum cut out for filler. Cut out may be no more than 6' wide by 10" long by 7" deep. Fuel lines must siphon from top only, No fuel lines bigger than #10. No auxiliary tanks. No fuel filters with more the 1/2 quart capacity. Fuel tank vent line must have an inline one way valve for the prevention of fuel spillage. Only one carburetor fuel log will be allowed and is limited to a maximum outside diameter of 1'.
Muffler is not mandatory. If one is used the exhaust must exit past the driver and must be directed to the rear of the car.. No pipe may face outside the car. Any manufacturer of exhaust header is allowed, but header material is limited to steel or stainless. No crossover pipes are permitted connecting the two banks of cylinders.
Any ballist weight must be mounted within the vertical planes formed by the frame rails, must be securely
fastened, and must remain stationary while racing.
One oil cooler, and one passenger car size battery will be the only exceptions allowed to be mounted outside the
TIRES AND WHEELS
Will be allowed to run any tire or any steel or aluminum wheel, up to and Including 92". Beadlocks allowed. No plastic wheels. Maximum tire size will be 29"x 11" The right rear tire softness will be 38 American Racer minimum.
Weight is taken with driver and no fuel added after race is finished. Must weigh 2450 lbs. Min. (Legal GM Crate engine 2350 lbs. Min.)
Track scales will be the official scales.
This class is reserved for North American passenger car V-8 engines with cast Iron blocks and cylinder heads. All engine parts must have casting or part numbers
on them for Identification. All engines must maintain stock bore and stroke combinations.
Engine Maximum Overbore
Chevy 350 ci., 4.00" bore x 3.480' stroke +.070"
Chry 360 ci 4.00" bore x 3.578' stroke +.0200
Chry 340 Ci 4.04" bore x 3.313' stroke +.0600
Ford 351 ci 4.00" bore x 3.5' stroke +.0601
A 4 cu. in. wear allowance is allowed for all manufacturers
Engines must remain stock as manufactured with the following exceptions,
May run a sealed 602 crate, Following the DIRT rules.
The engine block and all internal parts must meet stock specifications for Its make. No Bowtie or other performance type blocks allowed. Dart *LittleM" sportsman block, part #3115111 is allowed.
Cast iron OEM stock production heads or 180/200 DART Iron Eagle heads, straight plug or angle plug),-only. Chevy bow-tie, Chrysler W-2, and Ford performance heads are allowed providing they meet the rules and not fall into the category of unfair competition. The Chevy Vortec and the Ford GT 40 are not allowed. Cylinder heads must be from the same manufacturer as the engine block (except Dart). Milling or angle milling of the cylinder head to any amount is allowed. No epoxy or coating of heads is allowed. Heads may be ported but no material may be added. Intakes may be port matched to cylinder head only. Valve head sizes are optional providing they maintain stock OEM positioning In valve guides (distance apart and angles). Valve guide liners are allowed. Valve material must be one piece solid steel or stainless steel, no titanium, or sodium filled valves allowed. The only titanium allowed in these engines is the valve spring retainers. Any carbon fiber engine parts are illegal, Any amount of valve seats per cylinder head may be installed for the purpose of repairing a head. Any angle valve job will be permitted as long as it is done on a machine that cuts concentric to the valve guide center. Valve stern maximum and minimum diameter, plus or minus .005" must be as follows: Chevy 11/32, Ford 11/32", Chrysler 11/32". No hand grinding, sanding, blending or de-burring where a cutter or stone leaves off.
OEM stock production or aftermarket solid steel rods are allowed. No titanium, aluminum, or billet. Rods may not be polished. Rod lengths must be OEM specs for the engine block used.
Any steel or cast iron crankshaft is allowed providing it maintains stock stroke as manufactured for the engine
block used. Aftermarket OEM replacement crankshafts with holes drilled through crankpins are allowed providing they maintain stock appearance and specs. No lightweight cranks. Minimum rod and main journal sizes must be either Chevy, Ford, or Chrysler specs only. Minimum rod journal is 2.100". Knife edging, narrowing, or cutting down the diameter of the crankshaft counter weights is not allowed. No polishing of the crank.
Any brand, three ring flat top aluminum pistons only, No coating of any kind are allowed.
Any steel or cast iron, stock OEM vibration dampener is permitted providing it is not machined or altered in any way. No fluid or friction dampeners.
Any make hydraulic or flat tappet allowed. No roller cams, roller gear driven cams, mushroom lifters or lash caps are allowed. Shaft rockers and stud girdles are not allowed. Engines with stock OEM shaft rockers are legal. Roller rockers with optional ratios are legal. Lifters must maintain stock OEM diameters. Lifter bores must remain in stock OEM positions and angles, but may be re-bushed for wear. A flat steel lifter galley plate may be used to prevent engine damage in case of push rod failure.
May use a stock passenger car, cast iron 2 barrel Intake. An optional aluminum four barrel as cast box stock, spec manifold may be used. No work of any kind may be done on this optional manifold. No porting, polishing, welding, or acid dipping. Intakes may be port matched to cylinder head only. May use Chevy SP1, Ford 2980 or 2981, Chrys 2920
Any American Stock OEM 2 barrel carb. up to 1 1 1/16" throttle bore with no adaptor plate is legal on cast iron manifolds. The Holley carb. 4412 is acceptable and must run a maximum spacer adapter of 1 1/16 including gaskets. No modifications of any kind will be allowed to these carbs. except those listed below. Conventional round type air cleaners only, Air cleaners that provide ventilation through the top cover such as K&N are permitted. No air induction plastic carburetor inserts or other devices to direct air into intake, No air diffusers are allowed. CARBURETOR MODIFICATIONS ALLOWED ARE LISTED BELOW, ANY OTHER MODIFICATION NOT MENTIONED ARE NOT LEGAL.
Holes drilled in the throttle plates for proper idling
Drilling, tapping and plugging of unused vacuum ports.
Welding of throttle shaft to linkage arm
Drilling of idle or high speed air correction jets
Milling of center carburetor body metering block surface a maximum of .015" on each side.
Removal of choke plate and shaft
The jets may be changed as needed
MSD IGNITION WILL BE AN OPTION PART NUMBER 6ALN AMY RPM CHIP NO EXTERNAL AJUSTERS NO SOFT TOUCH NO CRANK TRIGGERS NO MULTIPLE BOXES ONE COIL
One point type distributors, coils must be stock. With any system used, only one coil will be allowed on the car. One 12 volt battery allowed.
No dry sump system is allowed, Oil must be in steel pan only, Oil pan must have 3/4" inspection hole for connecting rod verification on left side of pan. No external oil pumps or Accu-sumps allowed. No form of engine evacution system by internal or external driven pumps or by connection between exhaust system and valve covers, intake manifold or oil pan. Only two breathers on any valve cover will be allowed. Oil coolers will be permitted providing they are mounted under the left wing or under the hood only.
Must be cast iron only. Radiator fan must be steel only, No electric cooling fans or pumps.
Must remain in and be driven as stock OEM equipment. No electric fuel pumps are allowed.
Racing gasoline only. No nitrous or any other additives are permitted.