Colorado National Speedway

Colorado National Speedway 2015 Modified Coupe Rule Book Rev: 2-23-2015 Definitions: Box Stock: The part must remain unaltered. No grinding, lightening, porting, or polishing of any kind is allowed for any purpose other than to make the part fit in its intended place for its intended use. Interchanging parts to change performance unless specifically outlined within the rule book is strictly prohibited. Factory Stock: The part or series parts must remain unaltered. The part or series of parts must remain in the condition and perform as they were produced by the factory. Any changes made to increase performance are strictly prohibited. Bodies: Design optional, but within the following guidelines: 1. Shall be 1939 vintage or older 2. Body shall appear Vintage in appearance, construction and design. 3. No IMCA or dwarf type bodies. 4. Body shall not obscure the view of traffic to the car behind 5. All cars shall be neat appearing with no sharp edges at all times throughout the season 6. Bottom of body skirt shall be no higher than bottom frame rail 7. Dimensions a. Bodies shall be a minimum 36 high and 35 wide at the widest point. b. Bodies shall be no more than 66 wide at the widest point. 8. Any additional panels utilized to create down force are prohibited. 9. No wicker bills of any kind or size will be allowed on the body. Hood: 1. Constructed of fiberglass or metal 2. Shall cover the entire area from the front of the radiator to the front of the cowl 3. Shall be as wide in the back as the front of the roll cage 4. Shall extend over the full width of the radiator making certain all water outlets are covered 5. Securely fastened in place and required at all times when a car enters the track surface 6. Hood will not have more than a 10 degree forward slope 1

Floor or Belly Pan: 1. Shall be fabricated of metal 2. Shall be securely fastened in place 3. Shall cover the entire area from the front firewall to rear firewall and frame rail to frame rail 4. No unnecessary holes permitted Firewalls: 1. Shall be fabricated of metal no less than.025 thickness material 2. Shall be securely fastened in place 3. Shall be as wide as the body in the front 4. Shall extend from the belly pan to cowl height in the front 5. Shall extend from the rear frame rail to bottom of rear window opening 6. No unnecessary holes permitted 7. Hole in rear firewall allowed for driveline. 8. Sedans shall cover the top of fuel cell can to separate fuel cell from the drivers compartment 9. All firewalls to meet safety tech approval. Frames: 1. Type of frame optional 2. Shall be fabricated of steel 3. Stock frame rails shall be completely boxed to a minimum of 6 on both sides of the roll bar attachment points. 4. Frames shall be 1 1/2 minimum O.D. a..095 minimum wall thickness 5. Engine, seat, battery and fuel cell shall be completely inside frame rails 6. Engine offset shall be a Maximum of 4 to the left a. Off set shall be measured off of center line between the lower frame rails b. No cutting of frame rails to offset engine. 7. Engine setback shall be a Maximum of 38 a. Set back shall be measured from the centerline of kingpins or ball joints to the back of the engine block 8. All drivelines shall be protected with at least 2 driveline hoops providing 360 degrees coverage. One hoop shall be near transmission tail shaft and one within 40% of the length of the shaft. 9. A cross member minimum 1 O.D.... 083 inch steel tube utilized to triangulate the 2 main frame members is mandatory. The cross member must be directly within the drivers area. 2

Roll Cages: 1. Shall be fabricated of steel or 4130 Chromoly. 2. Minimum 1 ½ O.D. a..095 minimum wall thickness 3. All roll cages shall have a minimum of a 6-point cage construction a. 3 door bars on each side mandatory with a minimum of 2 rows of bars equally spaced running vertically between all horizontal bars. 4. The roll cage when measured with a straight edge from the top of the rear hoop to the top of the front hoop shall extend a minimum of 4 above the driver s helmet with the driver securely belted in place. 5. All roll bars shall have padding anywhere driver body contact is possible with the roll cage. a. SFI rated high density padding is mandatory on all bars surrounding the head. 6. All top four corners of the roll cage shall be gusseted. Bumpers: 1. Front and rear bumpers are mandatory. 2. Shall be fabricated of steel 3. Center of bumpers, front and rear shall be 18 from ground a. plus or minus 1 inch 4. Front bumpers a. Shall be a minimum of 4 wide and or maintain 4 of spacing between tubes b. Shall be as wide as the front of the frame c. Shall extend in front of front wheels 5. Rear bumpers a. Shall be a minimum of 4 wide and or maintain 4 of spacing between tubes b. Shall be no wider than the outside edge of rear tires. 6. No Sharp edges. Side Kick-Off Bars: 1. Shall be fabricated of steel 2. Shall extend to the outside edge of rear tires at a minimum. a. Plus 1 inch past the outside edge of the tires maximum. 3. No sharp edges 4. No solid bars allowed. 5. One piece of sheet metal maybe added vertically to the outside edge of kickoffs for the purpose of deflecting exhaust noise or increasing signage space. No wicker bills or material of any kind will be allowed to be mounted so that any down force is created. Must meet safety tech approval. 3

Seat: 1. Shall be constructed of aluminum 2. Shall be securely fastened a. A minimum of 6-3/8 grade 8 bolts and locking type nuts b. 2 bolts in bottom of the seat c. 2 on the back of the seat shall be no further than 16 from bottom of seat d. 2 bolts on the back of the seat within 6 vertically above the base of the seat. e. 3/8 fender washers shall be installed on each fastener surface that is in contact with the aluminum seat 3. Full head & shoulder containment seat is MANDATORY. 4. Head and Neck system (HANS) or similar restraint system is MANDATORY. 5. Driver s seat must set over the driveshaft with a maximum offset of 4. 4 offset is measured off of the center line of bottom frame rails. Seat Belt and Shoulder Harness: 1. Shall be SFI approved 2. Shall be a minimum of 3 wide 3. Shall not be older than 3 years from date of manufacture 4. Shall be a minimum of 5 point (anti-sub) type 5. Shall be securely mounted to the frame. Steering: 1. Steering type optional 2. Quick release steering wheel mandatory 3. Center of steering wheel shall be padded. 4. Minimum of 2 U-joints on the steering shaft to create a collapse zone in the event of a crash. Wings: Optional A wing is defined as an air foil that allows air to flow over a surface and under a surface with the intention of developing down force by accelerating the air speed under the surface of the air foil. 1. Only one wing shall be allowed. 2. Wings shall not obscure the view of traffic to the car behind 3. Shall be independently suspended above and away from the car. 4. 25 sq. ft. maximum combined surface area for any part of the wing creating down force. 4

5. Side boards a. Maximum 10.2 Sq. ft. per side b. Must be symmetrical c. Must be mounted symmetrically 6. Maximum of one (1) - 1 wicker bill shall be permitted on the wing only and cannot be installed on any other area of the car. 7. No Driver adjustable wings 8. No mechanically or hydraulically adjusting devices allowed Tires: 1. Size shall be stamped on tire 2. Manufacturer stamping shall not be altered 3. Right side and left rear tires shall be the current CNS track tire, Hoosier 3035/3045 4. Left front tires optional **Competitors will be allowed a 6-tire bank on the car's first night of competition and one (1) additional tire for each race meet completed. Wheels: 1. Steel or Aluminum only 2. Shall be no more than 14 maximum width 3. Wheel studs shall be a minimum 5/8 Shock Rules: a. Only one shock per wheel b. Only shocks cataloged from a reasonably recent period @ less than $225.00 Note: Price to include Racers Net; it will be the responsibility of the Driver/Owner to prove the cataloged pricing upon request from a CNS Official Suspension: Type optional: Wheel Base 90 minimum - Tread width 70 maximum a. Measured from the inside of the tire sidewall to the outside of the opposite tire sidewall at spindle height. b. No operator controlled, computer controlled or automatic weight transfer, weight shifting or weight altering devices or techniques. c. No chassis, shock adjustments are allowed from the driver s compartment (except brake bias) 5

Brakes: 1. Shall lock all four wheels Engines: OPTION 1 -"Big Engine Package Minimum PRE RACE total car weight 2300 lbs. With maximum 56% left side weight. (No Tolerance) (CNS Tech department will issue a 1.438 Restrictor Plate) subject to change **MUST RUN 4.86-1-Final Drive Ratio** American Manufactures Only Maximum 360 cid plus.060 overbore for cleanup. (-370.8 cid-) Blocks: 1. Must maintain Manufactures Casting numbers. no purpose built, specially cast or manufactured one of a kind blocks 2. No aluminum blocks 3. No roller bearing cam bearings Heads: 1. Aftermarket Steel heads allowed a. 23 degree valve angle only on Chevrolet heads b. Ford and Chrysler heads shall only run the valve angle that comes with that engine application stock from the factory. c. For inspection purpose a deviation of plus or minus 2 degrees will be considered based on the average of both heads. d. Heads shall be readily available from any parts store or catalog with that particular brand or manufacturers part number cast into that part. Camshaft/Valve Train: 1. Shall be Flat Tappet 2. No Roller Cams a. No roller cam bearings 3. Lifters shall be flat a. No radius lifters b. No mushroom lifters 6

Crank Shaft /Connecting Rods: 1. Steel Rods only a. No Aluminum Connecting Rods 2. SFI Rated front balancer mandatory Oiling System: 1. No external oil pumps 2. No dry sumps Fuel Management System: 1. One 4 barrel carburetor only, normally aspirated a. Any CFM b. 2 opposing throttle return springs required 2. No fuel injection 3. No external vacuum pumps Intake Manifold: 1. No Sheet Metal Intakes a. Intake manifolds shall be readily available from any parts store or catalog with that particular brand or manufacturers part number cast into that part. Part numbers shall be visible on any intake manifold or block. OPTION 2 604 Crate Engine: Minimum PRE-RACE total weight 2000 lbs. Maximum 56% left side weight NO TOLERANCE. **Gear Ratio 4.86 5.30:1 final Drive Ratio Mandatory** 1. Engines may be freshened for the purpose of returning a used engine to factory original performance and condition. Any alterations not outlined in these rules shall be considered prohibited. a. Factory seals are not required b. Engine still subject to all tech inspection procedures. c. Must remain within 5% of factory horsepower ratings as determined by the C.N.S. Modified Coupes d. 1.6:1 maximum rocker arm ratio is permitted. No shaft systems e. Valve Springs may be replaced with Comp Cams #26975 only f. Must run 650 cfm carburetor Must remain box stock (no porting or polishing) Jets, Squirters, and power valves may be changed or plugged 7

Due to the GM non-availability of the cylinder head specified Vortec Large Port Bowtie Cylinder Heads 25534446 for the spec engine the following will apply for the 2015 Season: OPTION 3 SPEC ENGINE: Minimum PRE-RACE total weight 2100 lbs. Maximum 56% left side weight NO TOLERANCE **Gear Ratio 4.86 5.30:1 final drive ratio mandatory** 1. Maximum 360c.i. a. Maximum bore 4.060 No tolerance b. Maximum compression ratio of 11.0:1 2. Carburetor a. One 650 cfm carburetor only b. Monday, March 09, 20158Must remain box stock (no porting or polishing) c. Jets, squirters, and power valves may be changed or plugged. 3. Intake Manifold/Heads Rev: 2-23-2015 for 2015 Any non-ported cast iron cylinder head with a combustion chamber 64 cc or larger and a valve size 2:02 or smaller will be allowed. Port matching will be allowed but may not extend more than 1 inch into port. Any non-ported intake manifold will be allowed. Any valve spring will be allowed. No titanium of any kind will be allowed on cylinder heads. a. Edelbrock Super Victor Intake Manifold part #2814 only Heads b. Chevrolet Performance Vortec Large Port Bowtie Cylinder Heads 25534446 c. Must remain factory stock d. No porting, polishing, or port matching e. Altering of valves or valve angles is prohibited f. Valve Springs may be replaced with Comp Cams #26975 only 4. Rocker Arms a. 1.6:1 maximum rocker arm ratio b. No shaft systems c. 3/8 or 7/16 stock or screw in studs only 8

5. Camshaft a. Maximum lift.520 measured @ zero lash @ zero valve retainer b. Mechanical flat tappet only c. No hydraulic or roller cams d. No roller cam bearings e. No gear or belt drive systems 6. Lifters a. Minimum.842 Tappet b. No roller, mushroom, hydraulic, or radius tappets 7. Pistons a. Flat top only b. Aluminum only c. Minimum of 420 grams per piston d..043,.043, 3mm ring package e. Minimum 3mm oiling ring thickness f. No stainless steel compression rings 8. Rods a. I or H beam steel construction only b. 5.7 length maximum c. Rod journal 2.100 minimum d. Plug required in the oil pan in-line with a rod for inspection 9. Crank Shaft a. Cast Iron or Steel Only b. 48 lbs. minimum weight. NO TOLERANCE (i.e. 47.8 is illegal) c. Main bearing 2.45 minimum d. Stroke 3.48 maximum e. No knife edging or undercutting of crank shafts allowed. 10. Harmonic Balancer a. SFI Mandatory b. Minimum of 6 diameter 9

11. Oil Pump a. Wet sump only b. No vacuum systems of any type 12. Oil Pan a. No crank scrapers 13. Misc. a. Titanium and/or composite materials are prohibited b. All engine components shall be steel unless the rule specifically states otherwise. Ignitions: 1. Type optional 2. No magnetos 3. No crank trigger ignitions Transmission, Rear end, and Driveline: 1. Standard 3 or 4 speed Transmissions 2. No Automatic Transmissions allowed 3. All cars shall be self-starting 4. All cars shall have a working clutch 5. Drive shaft must be constructed of steel a. Minimum 2 O.D.... 120 wall tubing. b. shall be painted white c. Shall have car number on drive shaft 6. No In and Out boxes are allowed 7. Scatter Shields a. a. If a car is using full flywheel and a stock type clutch disc and pressure plate; a scatter shield or safety bell housing is mandatory. b. All cars using flex-plates must have flex-plate explosion protection (i.e. scatter-shield, steel bell-housing, steel flex-plate shield, or bellhousing blanket) SFI approved highly recommended. 8. Internal-clutch type transmissions (Bert, Brinn, and Falcon) are allowed 9. No forward Gears may be closer in Ratio than 1.23.1 of the mandatory final drive Ratio of 1.1 10

Exhaust Pipes and Mufflers: 1. Exhaust types optional 2. Mufflers shall meet all current noise restrictions. a. 95 DBA at CNS Fuel: 1. Track fuel or pump gasoline only. No exceptions. a. Tech officials reserve the right to sample and test fuel from any car at any time. Fuel Systems: 1. Fuel cells mandatory 2. Fuel cells shall have foam installed in the cell 3. Fuel Cells shall be enclosed in Metal Can 4. Shall be securely mounted between frame rails 5. Refueling shall take place outside of the vehicle a. Filler tube shall be installed so that the person filling the tank remains on the outside of the car 6. Manual fuel pumps recommended. 7. Electric fuel pumps must be wired to the ignition switch. An impact switch is mandatory and must be mounted to the chassis or roll bar. Electric pumps shall be mounted outside of cockpit. 8. Fuel shut off valve mandatory a. Valves shall be clearly marked b. Valves shall be accessible from the outside of the car the car. 9. Fuel Tank Flapper Valve MANDATORY on all fuel cells Electrical System: 1. Battery shall be securely fastened between frame rails 2. Battery shall be equipped with a suitable cover if not gel filled 3. Ignition switches a. Shall be clearly marked ON and OFF b. Shall be easily accessible to a person outside the car. 4. Master switches mandatory a. Shall be mounted in center of dash b. Shall be clearly marked ON and OFF c. Shall be easily accessible to a person outside the car. 5. No Traction control devices (electrical or mechanical). 6. All batteries located inside the driver compartment must be gel filled or AGM. 11

Cooling System: 1. **1 Quart (minimum) Overflow tanks are mandatory** 2. Water only a. No alcohol b. No ethylene glycol (antifreeze) c. $100.00 Fine for all cooling liquid violations d. Water wetter or similar products shall be permitted 3. Cowling in front of radiator for the purpose of deflecting air into the radiator is permitted. One box for the purpose of cooling only shall be permitted. The box shall not exceed a 10 angle up or down and shall not extend further than 12 forward of the radiator. The cooling box must be symmetrical. Fire Suits: 1. All drivers are required to wear minimum one or two piece single layer fire suit with current SFI rating and in good condition. 2. Nomex underwear is required 3. Racing gloves are required 4. Racing shoes are required. 5. Head and Neck Restraint (HANS) or similar devices REQUIRED 6. All safety equipment shall be inspected periodically Helmets: 1. Shall be Snell SA2010 or newer 2. No open face helmets. Weight: See Engine Rules: 1. Any rule indicating car weight is measured pre-race with driver in a normal driving position with helmet. 2. No items shall be passed to the driver before the car is scaled. 3. Manipulation of this process may result in penalties. Gears: See Engine Rules: 12

Fire Extinguishing System: 1. On board fire suppression SYSTEM is MANDATORY. Minimum of (1) one discharge nozzle to cover driver's compartment and should be installed per manufacturer's specifications.. Installation subject to tech inspector approval. Miscellaneous: 1. All drain plugs shall be drilled, securely installed and safety wired a. Rear ends b. Transmissions c. Oil pans, tanks, and plugs Radios: 1. Radios are MANDATORY. Spotter to driver communication required at all tracks. Either one way or two way communication acceptable Transponders: 1. A transponder will be mounted no farther forward than the rear of the driver's seat (a minimum of 106" from the leading edge of the front nerf bar). Transponder must have an unobstructed view of the racetrack. 13

Colorado National Speedway 2015 Modified Coupe Rule Book Owners: Jim and Sue Nordhougen Head of Tech: Mark Rush General Manager: Brian Laurence CNS Marketing Department Track Photographer: Joe Starr CNS Webmaster & PR: Eric Guttormson Track Announcer: Marc Moser Assistant Promoter: Colleen Lyons-Cubides HOTLINE: 303-665-4173 PHONE: 303-828-0116 FAX: 303-828-2403 Email: info@coloradospeedway.com Mailing Address Colorado National Speedway 4281Graden Blvd Dacono, CO 80514 14