2024 FLORENCE MOTOR SPEEDWAY STREET STOCK RULES

1.0 - ENGINE/CARB/WEIGHT COMBINATIONS

*Yellow book blueprinted crates must add 75 lbs. Ex: Decking Block to specs, cutting cylinder heads to

minimum cc’s, no narrow bearings, etc.

2.0 - GENERAL ELIGIBILITY

1. Participants must be at least 12 years of age.
2. American made cars only.
3. No convertibles, station wagons, or pick-ups.
4. Camaros, Novas, and Firebirds will be allowed but must retain stock rear leaf spring suspension.
5. Entire interior must be removed.
6. All holes must be patched in firewalls and floor pans.
7. Two-way radios will be permitted for use.
8. All cars must have a spotter in the spotter’s stand for every race.

3.0 - WEIGHT RULES

1. Cars will be weighed pre OR post qualifying and must meet minimum weights. Cars will be weighed again post-race and will be allowed 1 pound per lap burn off. (Ex. 50 lap race = 50 lbs burn off)
2. No fuel, water or oils may be added after the race to any cars.
3. Maximum 49% percent rear weight checked with car filled with gas.
4. All cars maximum 55% left side weight.
5. Declared weights (including any penalties for engine, body, etc.) must be clearly marked on driver side window with sticker.
6. Lead will only be allowed in MINIMUM of 5 lb pieces.

4.0 - CHASSIS/FRAME

4.1 - GENERAL

1. Frame must remain stock specs from front of steering box to center of rear-end housing or subject to weight penalty.
2. Full frame car must remain full frame.
3. Frame must be same dimensions from front to back (length and width).
4. Frame and cage may be tied and reinforced together by rectangle, square or round tubing for safety.
5. Front clip must be OEM and may be notched for fuel pump and oil pan clearance.
6. Cars must have a complete steel firewall and floor pans. No boxed Interior. Sheet metal must be lower than driveshaft tunnel.
7. Any car that does not have an OEM floorboard will be assessed a 50 lb weight penalty.

4.2 - WHEELBASE

1. Wheelbase must be within 1″ of factory specs for make and model of car with a minimum of 105”, allowing 1” tolerance for alignment.
2. Any car that is not within 1″ of factory wheelbase specs will be allowed to compete with a 100 lb. weight penalty.
3. Wheelbase must be within 1” from side to side.

4.3 - RIDE HEIGHT

1. Minimum ride height for the body, chassis, and any component mounted to the body or chassis is 5″.
2. Minimum ground clearance for oil pan, sway bar, exhaust pipes, and headers is 3″.

4.4 - REAR END

1. A floater rear end will be allowed. Straight spine only.
2. OEM Limited Slip, OEM Open, Locked Up Spool, or Detroit Locker Allowed.
3. No Gleason or Gear Driven Devices allowed. No Tru-Trac allowed.
4. No cambered rear ends allowed (max .4 degrees).
5. No rear gear rule.
6. Steel third members.

4.5 - TREAD WIDTH

1. Maximum tread width for front and rear is 66 ½” measured from outside of left tire to inside of right tire at spindle height.

4.6 - SWAY BAR

1. Front sway bars must be stock type or Howe type.
2. Maximum diameter 1.375”.
3. No rear sway bars allowed.

4.7 - FRONT SUSPENSION

1. Cars must retain stock OEM spec parts.
2. Lower A-frames must be in stock mounts and stock locations.
3. UNALTERED lower A-Frames must remain stock OEM and must be same length on right side and left side excluding ball joints and bushings.
4. Lower A-frames, Spindles, trailing arms, and pitman arms must remain stock OEM parts.
5. Centerlink may be aftermarket.
6. Upper A-frame mounts may be altered.
7. Tubular upper A-frames may be used.
8. Tie rods may be steel sleeve with steel heims. Heim joints allowed with washer bigger than heim joints.
9. Front hubs and rotors must be same size and in OEM location and not be lighter than OEM stock.

4.8 - REAR SUSPENSION

1. Leaf spring suspension can have rear adjustable shackle plates to raise or lower car since there is no screw jacks.
2. A leaf spring car will be allowed adjustable lowering block to straighten rear end.
3. A trailing arm car will be allowed eccentric or steel heims to be able to straighten rear end.
4. Truck arms will not be allowed on any chassis.
5. Pinion wedges or adjustable top links allowed to adjust pinion angle.
6. Chassis hookups must be OEM for make and model chassis.
7. For any car, if your rear suspension chassis hookups/pickup points are changed or altered from stock OEM design you must add 100 lbs to total weight. Including an adjustable track bar on frame connection.

4.9 - SPRINGS AND SHOCKS

1. One steel shock or strut per wheel, $175 each claim rule.
2. No travel limiting devices of any kind allowed. No coil binding of springs, chassis stops, or bump stops.
3. Strut equipped cars may take guts out of struts and mount an external shock on car.
4. Ride heights can be checked at any time during the event.

5.0 – ENGINES

5.1 - CRATE ENGINES

5.1.1 - GENERAL ELIGIBILITY

1. The following crate-type engines will be permitted and must be used as supplied by the manufacturer and/or per the specifications manual provided by the manufacturer: i) General Motors #88958602 / ii) General Motors #88958603 is legal with a 75 lb weight penalty.
2. Crate motor technical specifications will be based on the following manual: i) GM Performance Parts Circle Track Crate Engine Technical Manual – Revised May 2010
3. Crate engines are designed to cut the cost of racing. Run them as supplied from the factory to ensure legality. Any competitor found to be tampering with these engines will be disqualified and forfeit monies and points won.

5.2 - BUILT ENGINES

5.2.1 - GENERAL ENGINE CHARACTERISTICS

1. Only standard production engines from manufacturer allowed. GM 350 cubic inch maximum, Ford 351 cubic inch maximum, and Chrysler 360 cubic inch maximum.
2. Maximum of .060 overbore permitted.
3. No high performance parts allowed unless listed below.
4. No polishing or coating any parts including inside of block.
5. No electric fuel pumps
6. OEM Stock or OEM replacement parts for OEM cubic inch including cylinder heads, pistons, crankshaft, and steel connecting rods only.
7. Flat top or dish three ring pistons are permitted. Pistons may have min “two eyebrows”.
8. Crankshaft with stock stroke must be retained. 50 lbs min weight. Crank journals may be ground for undersize bearings. No lightening or drilling. No other machine work will be permitted.
9. Enlarged OEM oil pan permitted.
10. OEM stock production steel heads only with OEM steel valve size and combustion required.
11. Piston must not extend above top of block.
12. Four bolt-main blocks permitted.
13. Aftermarket pulleys allowed.
14. Unaltered Edelbrock 2101 or 2116 or steel intake allowed on built engine.
15. 602 GM Crate intake ok.

5.2.2 - HEADS AND CAMSHAFT

1. Stock production steel heads only. No angle plug heads. Vortec heads must have a restrictor plate on a .450-.480 cam lift built vortec head engine with a max 1.357 spacer plate adapter with no bevel. No restrictor plate required on low lift camshaft (.449 and under). Stock Replacement (SR) head will be allowed with a 100-pound penalty.
2. NO modifications, no porting or polishing. No grinding of any kind. Standard 3 angle valve job allowed.
3. Chev 70cc min; Ford (Clev) 68cc; Ford (Win) 58cc; Chrysler 68cc min. Chev Vortec 60 cc min.
4. OEM valve size for cylinder head required. Steel valves required. Any Chev head with cc’s that are below minimums or any valves bigger than 1.94/1.50 will be required to add a 100 pounds or 50 pounds for each. Tech Man may approve other combos with a weight penalty.
5. Cam and lifters solid or hydraulic with a maximum lift of Chev .480, Ford .512, Dodge .500. Lift will be measured at the valve retainer as run in the race. Any Ratio Rocker to achieve max lift is ok! Any Cam that lifts under .450 or over .480 is eligible for a weight break/carb or weight penalty at tech discretion.
6. Stock OEM valve spring and retainers. Aftermarket rocker arms allowed. Poly- locks ok. Studs may be pinned, screw-in studs and guide plates permitted. Valves must be steel.
7. Valve size maximum: a) Chevrolet 1.94 intake 1.50 exhaust // b) Ford Cleveland 2.05 intake 1.65 exhaust // c) Ford Windsor 1.89 intake 1.60 exhaust // d) Chrysler 1.90 intake 1.60 exhaust
8. Any engine that does not conform to the above engine rules may be able to add weight and/or restrictor plate to be able to race.

5.3 - GENERAL ENGINE RULES (ALL ENGINES)

5.3.1 - CARBURETOR

1. Holley 350 CFM 2-barrel carburetor (HP Part# 0-7448 or 0-80787-1) allowed on built or crate engines.
2. Holley 500 CFM 2-barrel carburetor (HP Part# 0-4412C or 0-80583-1) allowed on crate engines only.
3. Note: New style Holley 500 CFM “Ultra XP” carburetors not allowed.
4. Note: New style cast aluminum 4412 not allowed.
5. No alterations except choke hardware may be removed and all vacuum ports must be plugged.
6. No polishing, grinding, or machine work allowed on any part of carburetor.
7. Only stock passenger car OEM boosters allowed. No modifications allowed. No bevels.
8. Base plate must not be altered in shape or size.
9. All carburetors must have choke horn. Choke mechanism may be removed.
10. Any attempt to pull outside air other than through the venturi is not permitted.

5.3.2 - CARBURETOR SPACER PLATE/GASKETS

1. Crate Engines: a 3/4″ centered non-adjustable aluminum carburetor spacer plate is allowed with a onepiece gasket (maximum thickness of.065 inch) on each side of the spacer plate. Carb spacer must be straight cut, no bevel. No Coated or Anodized Spacers allowed.
2. Built Engines: a 3/4″ centered aluminum carburetor spacer plate is allowed with a one-piece gasket (maximum thickness of.065 inch) on each side of the spacer plate. No Coated or Anodized Spacers allowed.
3. Air Cleaner base must not be above choke horn.

5.3.3 - EXHAUST

1. Headers allowed.
2. Exhaust must not be over 3 ½” diameter. May exit from underneath the car.
3. Exhaust may exit the right or left side of the car for safety.
4. No dr. gas or merge collectors.
5. If exhaust exits out the door it must be lower than driveshaft tunnel with as minimal floor trimming as possible.
6. Exhaust must be covered in 24-gauge steel.
7. No header wrapping.

5.3.4 - IGNITION/ELECTRICAL

1. A HEI style aftermarket distributor may be used and may be locked for the built motor.
2. Coil and module must remain in distributor.
3. No 16V systems allowed.
4. No traction control devices of any kind will be allowed.
5. No electric fuel pumps allowed.

5.3.5 - COOLING SYSTEM

1. Aluminum radiators permitted.
2. Water only, no antifreeze permitted.
3. Radiators must be stock appearing and installed in the stock location.
4. All air to the engine must pass through the radiator. No ducting or directing air to the carburetor allowed.

5.3.6 - ENGINE LOCATION

1. Engines may be interchanged from one body manufacturer to another.
2. A full steel engine firewall may be notched and plated or moved back to allow engine to be located. Excessive moving or cutting could result in weight penalty by tech official.
3. Engine must be centered in chassis. #1 spark plug in line with upper ball joint.
4. Maximum crankshaft height is 12” measured from the center of crank pulley to the ground.

5.3.7 - AIR CLEANER

1. Standard round air cleaner only.
2. No fresh air or induction systems allowed.
3. No directing fresh air to the carburetor.
4. No flow control air cleaners allowed.

6.0 - DRIVELINE

1. Stock OEM type working torque converter, min. 10”.
2. No lock ups
3. Straight Drive Clutches and pressure plates must remain OEM stock.
4. No lightening allowed.
5. Clutch pressure plate, disc, flywheel, and flywheel bolts must weigh 33 lbs. minimum.
6. Standard OEM production transmissions 3 or 4 speeds will be allowed to compete.
7. All gears must work.
8. No overdrive gears allowed.
9. Must use a steel blow proof bell housing if using OEM stock type clutch.
10. 7 ¼ or larger metallic clutch will be allowed with a 75lb weight penalty and may use a metal bell housing.
11. A hydraulic throw out bearing will be allowed.
12. Starters must mount in stock location.
13. Steel driveshaft only. Must be painted white with at least one driveshaft loop.

7.0 - BODIES

1. Bodies must be steel, absolutely stock appearing - no chopping or lowering of bodies in any way.
2. Factory OEM roof must be used. 50 pounds must be added for ANY type of other roof than steel roof.
3. Aftermarket fiberglass roof allowed with weight penalty.
4. The top of the rear quarters must be OEM.
5. Aftermarket OEM replacement front fenders and lower quarters may be used.
6. The hood, deck lid and doors may be aftermarket.
7. Front of hood must be securely fastened.
8. Metal rear deck must be securely fastened.
9. Third generation Camaros are allowed in the series.
10. Non-approved Street Stock body is subject up to 50 lbs weight penalty or restrictor plate. a)Penalties assessed for each non-steel section of the body broken down into 4 parts: Rear quarters, doors, front fenders, and roof. If you have 1 or 2 of those panels non-steel add 25 lbs to total weight. If you have 3 or 4 of those panels non-steel add 50 lbs to total weight.
11. A maximum 5″ tall x 60″ wide spoiler will be allowed (300 max square inches). Factory spoilers size allowed.
12. Hood scoops will be allowed. Open at windshield is ok.
13. Rear tail must be enclosed with a stock appearing bumper cover.
14. No right side windows allowed.
15. Vent windows allowed 12-inch max and will be checked before race.
16. No current aftermarket LM body.
17. All bodies must be tech man approved.
18. All body parts must be securely fastened. Any competitor with body parts that appear to be loose or not securely fastened will be black-flagged.

8.0 - BRAKES

1. Single metal piston brake calipers OEM design allowed and all 4 brakes must work.
2. Brake proportion valve and/or brake bias allowed but must be out of reach of the driver.

9.0 - TIRES/WHEELS

1. Teams will compete on scuff 10″ Hoosier race tires purchased from the track.
2. No softener or tire treatment of any kind allowed.
3. Racing wheels allowed with a maximum width 10”.

10.0 - SAFETY

10.1 - ROLL CAGE

1. Minimum 4-point roll cage mandatory, two points in front of the driver and two behind.
2. Mandatory at least 4 door bars on left side, 3 door bars on right side.
3. Cage must be welded in a professional manner and is subject to approval by tech personnel.

10.2 - FIREWALL

1. Car must have a front and rear firewall between the driver, engine compartment, and fuel cell area. Minimum height 10” from ground.

10.3 - BATTERY

1. Battery must be in a full closure box and be securely fastened in front of rear end or in driver’s department.
2. Master On/Off switch must be installed and easily accessible by safety crew.

10.4 - SEATS

1. Aluminum factory made racing seats required.
2. Absolutely no homemade seats.
3. Seats must be mounted in a manner acceptable to series officials. At least 6 bolts in seat.
4. Seats may not be mounted to the floor pan.

10.5 - SEAT BELTS

1. Seat belts must be a 5-point harness type.
2. Seat belts must be no older than 5 years old.
3. Seat belts must not be mounted to the floor pan.
4. Seat belts must not cross areas that may cut the belts, i.e. not across sheet metal attached to a roll bar.
5. Seat belts must be replaced if they are worn or the edges are frayed.

10.6 - WINDOW NET

1. An approved window net must be installed on the driver’s side window. Full size window nets only.
2. Window net must release from the top and drop down.
3. Window net bars must be substantial enough to contain the drivers arms in the event of a rollover.

10.7 - FIRE EXTINGUISHER

1. All cars are recommended to have an onboard fire extinguisher.
2. Extinguisher should be mounted so the charge gauge can be checked by series officials.

10.8 - FUEL CELL

1. A made for racing fuel cell (maximum 22 gallons) with foam is recommended.
2. Fuel line must run through steel tubing if running through driver’s compartment. If running under car must be securely fastened.
3. All cars must run 100% track race fuel or 100% non-ethanol pump gas. No mixing of gas or additives.
4. Fuel line through car must be painted red.

***We reserve the right to change or adjust these rules at any time to ensure fair competition. This could include but is not limited to adding/reducing weight and/or adding a restrictor plate as determined by tech officials. All decisions by officials are final.***