For the purposes of this rule book and governing events at the speedway, the word "stock" means: - Available on stock passenger car models, from the car manufacturer, installed per the manufacturers specifications, with no modifications, visual or technical, stock appearing, stock performing unless as otherwise noted in this rule book. All items not mentioned are to be Stock.

It is our intent to provide a class of cars which:

Are fast and challenging to drive but less expensive to build, operate and maintain than Pro Stock class vehicles. These cars will provide close, exciting competition for the fans and the competitors with the emphasis being on the driver, his crew and their setup and driving skills. This class is a logical choice for every driver who wishes to ultimately race in the Pro Stock class at the speedway.

North American, front engine, rear wheel drive cars, only. No sports car models.

108" minimum wheelbase with not more than one inch variance (+ and -), side to side.
Stock length as registered on your race application.
No Camaro front frame sections or equivalent.

Models must remain Chev on Chev, etc.

Stock except as otherwise stated.

Chev 350, Ford 351 (Windsor) or Dodge 360 ci engine. Open chamber heads only.

Maximum compression ratio of 9.0:1 (9.0:1 = 9.0:1)

Heads must have had an original combustion chamber of:

Chev 76 cc

Mopar 67 cc

Ford 60 or 69 cc (Depending on the piston)

- GM head - Maximum intake diameter of 1.94", maximum exhaust diameter of 1.50".

- Ford head - Maximum intake diameter of 1.84", maximum exhaust diameter of ï.55".

- Dodge head - Maximum intake diameter of 1.88", maximum exhaust diameter of 1.5I7".

Steel retainers must be used.
Stainless steel valves are allowed.

Minimum weight for the Piston and rod assembly is 1350 Grams.

Dished or flat top, cast or forged, 4 eyebrow pistons.

CAM - Stock Lift. Any duration with a Maximum Valve Lift as follows;

Valves must not have over zero lash clearance
Maximum over bore allowed without penalty is .030.
Any larger overbore must be brought to the attention of the tech prior to the start of the season or race event.

A steel kick out style oil pan is allowed.

Any car which wins three features is eligible to have it’s engine claimed by the Speedway.

The Claim amount is $3950 (plus tax).  Anyone refusing a claim will lose his points and purse for that event. If an engine is claimed it is the responsibility of the Claimee to remove it before the car can be removed from the speedway.

Failure to do so will result in disqualification.

SPEC ENGINE - An inexpensive, reliable and competitve Spec Crate engine is available. 

For information on the crate engine please click here.

Any steel oil pan may be used

No, dry sump systems

Valley trays may be used

Aluminum allowed in stock location. Hood must close without modifications
One electric fan may be used if a Stock Steel (minimum 4 fin) operating fan is installed
Water is the only coolant allowed
Cars which have other coolants will be fined for creating an environmental and driving hazard
Over flow cans must remain

Stock 500 cfm HOLLY Carb. # 4412 only
Choke assembly may be removed
Serial numbers must be readable
No Barry Grant Carbs

A Carburetor Claim will be in effect
Any carb may be claimed by the speedway for the value of a legal replacement Carburetor, including taxes
See Engine rules for details on refusing a claim and penalties
Two return springs are compulsory
A 1" thick spacer plate is permissible
GM and Mopar are allowed two stock type gaskets, one thin and one thick
No carb hats or air deflecting devices are allowed

Stock Air filter housing only

The following manifolds will be legal:

Stock Ram Horns
180 Degree Header up to a maximum of 1 5/8 inch outside tube diameter with up to a 3" collector, joining into one 3 ½ inch outside diameter exhaust for at least 1 foot prior to exiting
Exhaust must be made in such a way that gasses are directed away from the drivers compartment and away from any areas of possible fuel spillage. May not pass through door panel. Must point down toward ground and outward
Exhaust must be covered if passed through the car
Exhaust must extend behind the driver and exit on the right hand side of the car one foot in front of the rear wheel
Mufflers are not required

Stock
A 3 or 4 speed (steel cased) manual transmission is allowed
If a 4 speed transmission is used both 2nd and 3rd gears must not exceed the maximum allowed overall gear ratio of 530.

No variable ratio transmissions allowed

A Clean drivers fire suit is mandatory. 

A minimum, 4-point safety harness no older than 5 years, fastened to frame or roll cage

A Snell 85 registered helmet is required to be worn on the track

A minimum of 3 inches of clearance between the drivers helmet the overhead roll cage bar is required

All glass except windshield must be removed
Windshield must have safety glass or Lexan

Quarter windows and back windows are optional, and must be made of the same material as the windshield

Drivers window net is mandatory

Must have a minimum 2 1/2 lb.. fire extinguisher in the race car, securely fastened, within easy reach of the driver, and with recharge date no later than January of current year.

If battery is in drivers compartment, it must have a protective covering and be securely fastened to the floor

Every car must have a kill switch (shut off switch), located on or near the window opening on the drivers side (where windshield wiper was originally mounted or in front of drivers window opening)

Stock appearing

Steel , fiberglass, or aluminum body or kits allowed

Safety retainers on hoods are required
Trunk lids must be functional
Body must be centered on frame and retain its stock appearance, dimensions and angles
Must have all doors, fenders, trunk lid and hood on the car when the race day begins

A Complete steel firewall and floor boards around the driver of 22 gauge steel or better is mandatory

Aluminum is allowed elsewhere in the interior but steel is recommended for optimum fire safety

An after market rubber nose and tail "cones" are allowed, providing they match the body

No ground effects are allowed

A maximum 5" x 60" trunk deck spoiler is allowed
No side boxing of the spoiler

No, holes in hood. No, cowl induction. Hood must fit against windshield. 1" Tolerance

Minimum Ride Height for GM Metric cars = 6" as measured from any part of the frame to the ground

Minimum for all others with longer than 108" wheelbase is 4"

A 5" diameter, maximum, left side mirror is allowed. Mirror must be inside the car body. A Rear mirror is allowed

The back of the drivers seat to the center of the rear housing should measure no less than 25"

Rub rails, must be of flat aluminum and must be flush with the body with bolts countersunk and have no sharp edges

Note: Ford and Dodge power trains may run on a stock GM A Body Chassis. Otherwise car must be GM on GM, Ford on Ford, and Dodge on Dodge

No, mismatching parts

The following body guidelines will apply per the corresponding body measurements templates

"A" Minimum Front Nose Height = 18 "

"B" Maximum Front Overhang = 45"

"C" Minimum Window Opening = 16"

"D" Maximum Rear Window Length = 37"

"E" Minimum Body "Side Panel Clearance" to the Ground = 4"

"F" Maximum Rear Bumper Height = 17"

"H" Minimum Roof Height = 47"

"J" Minimum Door Height at the Rear = 35"

"K" Maximum Quarter Panel Height at the Rear = 35"

"M" Maximum Rear Deck Length = 23"

Spoiler must be no more than 60" long x 5" high.

No roof rails or wings

No side windows

No "cut down" body panels

Cars, especially top teams, found outside these guidelines in one or more areas will be penalized and or required to modify to the guideline based on competition.   Top teams should adhere to these rules strictly to avoid penalty.

All panels and windows or windshields must be braced to prevent bowing at race speed, as necessary.

"Mother of Downforce" or other high performance body sytles are not allowed.

A full 1/8" thick lexan windshield is required.
A rear window is recommended for better performance due to the higher speeds at the facility.

Dodge or Ford running on a GM Metric Chassis must run a full Dodge or Ford Power Train.

Anyone wishing to run Dodge or Ford power on a GM Chassis must receive prior written consent.

Dodge or Ford on a GM Chassis may be subject to weight adjustments to ensure fair competition.

Front quarter fender and side of the nose must remain open for "Driver Contingency Award" sponsors

Top 8" of Windshield, full width, must remain open for the Class Points Fund Sponsor

Bumpers must be used both front and rear. Bumpers can be reinforced from behind.

Click here to view the Body Template


The top 8" of the Windshield must be kept open for the class sponsor.  In addition the space behind the front right wheel and in fron to of the door numbers must be left open for contingency award sponsors.

Stock.

Master cylinder must be under hood in stock location.

Stock type aluminum brake drums are allowed.

Braided Steel Brake lines are allowed.

Stock.

You are allowed a mini locker, which is a piece of pipe to join the two axles. Or, you may weld your axle
gears.

Stock.

Must have blow proof bell housing or scatter shield around bell housing at least 1/4 inch thick or approved blanket. 180 degrees around, is required on all cars with manual transmission.

Automatic transmissions must have stock torque converter. Torque converter must have a scatter shield.

A minimum 21 lb stock steel flywheel is required.

Stock clutch plate, measuring a minimum of 10 ½ ". 

A minimum weight for the clutch and pressure plate will be announced for 2007. 

Steel roll cage constructed of no less than 1 1/2 - .095" wall - tubing around driver or any pipes specified below.

Tubing around the driver recommended as 1 ¾ - .095 recommended.

No exhaust pipe is allowed.

Must be welded directly to the frame of the car.

Roll cage can not be set back on the frame.

Must be four upright pipes joined at top with four pieces of pipe to form a top "hoop".

Uprights must be welded directly to frame and ahead of raised portion for rear wheels.

The bottom of top hoop must be a minimum of 3" above the top of the drivers helmet.

Must extend the full width of the roof so that the roof will be supported on the passenger side as well as drivers side.

A bar from the frame to the driver' s door is required to protect the drivers feet .

There must be three pipes a minimum of l 1/2 inches in diameter and .095 thick on the inside of drivers door between front and rear roll bar.

1 ¾ " recommended.

It is required that a minimum 1/16" plate be welded between or over (covering) these door bars to form a solid mass.

Fuel cell protection bar is required.

Roll cage must have two braces going back to the frame at the rear for support.

Drive shaft must be painted white.

N0, aluminum drive shafts.

Safety loops must be made for drive shaft, front and rear.

Stock.

Spring wedges may be used in coils.

Single coil springs only may be used. Lowering blocks may also be used.

Any spring may be changed as long as it is the same style after-market or otherwise.

All springs must be in stock location.

Jacking Bolts allowed.

Upper control arm may be cut to allow clearing of the jacking bolt.

Spring pockets may be reinforced or cut out to allow a longer spring. Stock 2 x 3 tubing material may be used to replace the frame from the rear housing to the back.

Wheel base may not vary more by more than 1" from one side of the car to the other.

Stock sway bar remains in stock position on frame and lower control arm. Sway bar may be adjustable at lower control arm.

If chassis came with sway bar on the rear, it may be used, as long as it remains in stock location.

A 6" tubed upper control arm is allowed.

Grandfathered Leaf Spring Cars may compete and may be subject to a competition penalty as necessary.

Ford Crown Victoria or Chev Caprice frame may be shortened to 108".  Frame rails must be at least 54.5 " long if shortened and all 108" rules will apply (eg. ride height, crank height, engine setback. etc.)  

The speedway is announcing, for planning purposes that beginning in 2008 a new chassis will be allowed.  This will not obsolete the existing chassis but will provide a more readily available and lower cost alternative for competitors who wish to build a sportsman car.   Details will follow.

Maximum of 55% left side weight.

Maximum 45% rear weight.

Minimum total weight for all cars will be 3000 lbs with the driver in position, full of fuel.

Car must be full of fuel to start each race.

Shortened full size chassis' may have weights adjusted in the interest of fair and close competition.

A minimum weight, after the race, may also be required as deemed appropriate by the officials.

Must be enclosed in a steel box, installed in trunk with filler neck inside of trunk.

Four Drainage holes should be drilled in the bottom of the steel box to not allow gas to lay in the box.

Fuel tank cannot be lower than the middle of the axle tube.

No electric fuel pumps or pressurized fuel tanks.

Must have full 22 gauge steel fire wall between gas tank and driver.

Gas line must be under floor. Regular (81 Octane) gas only. Maximum specific gravity =.765.

Track tire for the class is the Hoosier 890 purchased from the CENTRE
Tires will be durometered and documented each week
All tires must meet an average minimum durometer rating of 62 at 150 degrees (or less) prior to and after the race. No tolerance. 
To ensure the lowest cost for all competitors and eligibility for the sponsors points fund teams must purchase their tires from the CENTRE
This will ensure the lowest costs for all competitors

Steel wheels, 10" maximum. Larger wheel studs are recommended
Tires are not to extend past the body more than 2"
Maximum tread width of 68" measured from outside of tire to inside of tire

All competitors are encouraged to notify the speedway prior to April 1st of your requirements so that we have enough supply.

Note:  CENTRE for Speed Sportsman competitors may trade-in used Hoosier 890 Tires prior to the season beginning and receive a $20 credit toward new tires for each used tire traded.  Only tires that have been traded to the Speedway are eligible to be used by Street Stock competitors.  This will ensure the lowest cost and fairest competition for all competitors.  New for 2008 will be a tire trade-in date(s) TBA.  Sportsman will have the opportunity to trade in tires on these dates only.      

No two way communications equipment is allowed. 
A Scanner is required
Only the speedways race control channel may be coded in the scanner