OXFORD PLAINS SPEEDWAY
Route 26, Oxford, ME 
Phone: (207) 539-8865 

2011 RULE BOOK

For questions or clarification, please contact Randy Varney

LATE MODEL STOCK

*NOTICE*

Any and all Late Model Competitors who wish to have the opportunity to race in a non-OPS ACT event, MUST be ACT legal and have a registered ACT seal on the engine.

NO EQUIPMENT WILL BE CONSIDERED AS HAVING BEEN APPROVED BY REASON OF HAVING PASSED THROUGH INSPECTION UNOBSERVED. THE TECHNICAL DIRECTOR SHALL DETERMINE AS TO WHETHER ANY TYPE OF CONSTRUCTION, DESIGN, OR INTERPRETATION OF ANY RULE SHALL BE ACCEPTED.

OXFORD PLAINS SPEEDWAY RESERVES THE RIGHT TO UP-DATE, MODIFY, ADD, OR DELETE RULES AT ANY TIME IN THE INTEREST OF PROVIDING PARITY FOR ALL COMPETITORS. ADDITIONAL REQUIREMENTS MAY BE MADE VIA OFFICIAL ENTRY REGISTRATION, TECHNICAL BULLETIN, OR MEETING ANNOUNCEMENT, WHICH AUTOMATICALLY AMENDS SPECIFICATIONS HEREIN.

3-1 COMPETING MODELS AS SELECTED BY OPS

3-1.1 Late Model Stock Car Races

Oxford Late Model Stock Car races are open to eligible models of American made passenger car production cars.

American-Canadian Tour (ACT) registered and ACT rules legal cars may compete under ACT rules.

3-1.2 Approved Competition Models

The following cars are the eligible models approved for competition:

Impala SS, Monte Carlo, Pontiac Grand Prix, Ford Fusion, Taurus, Dodge, Charger, Intrepid RT Toyota Camry – Five Star - #723-142

All other makes and models must be approved by Oxford Plains Speedway.

The Only 23 Series Five Star Narrow Fenders Allowed will be:

660-23PLW – Narrow Plastic White left

660-23PRW – Narrow Plastic White right

660-23PLB – Narrow Plastic Black left

660-23PRB – Narrow Plastic Black right

3-2 GENERAL BODY REQUIREMENTS

3-2.1 Appearance

(a) Cars must be neat appearing and have complete bodies. OPS approved body may be either stock or aftermarket steel or aluminum and a stock steel or fiberglass roof is required. No carbon fiber body panels permitted. ABS plastic front fenders may be used and must match body used. Front and rear bumper covers may be stock or aftermarket rubber. Fiberglass hoods and window frames permitted. All body panels must be complete in length and width, nose panel may be narrowed a maximum of 4 (four) inches.

A long body template will be used to check body configuration.

(b) Full stock dimension windshield is mandatory. Full stock dimension rear window is mandatory. Minimum 1/8 inch thick Lexan material must be used for front and rear windows. Three internal windshield braces spaced at least on 5 (five) inch centers and roughly centered upon windshield constructed of minimum of 1 (one) inch by 1/8 inch thick material is required. Rear window must be securely mounted with straps or edge clips made of metal, steel or aluminum and be internally braced so window will not distort under race conditions.. Rear quarter panel windows may be covered with Lexan material. No tinted windows.  Rear side window may have approved air vents for driver.

“A” pillar windows are not to exceed 6” in any direction measured from front of door opening.

No interior air deflectors allowed.

3-2.2 Overall Car Weight

All weight will be with gas, oil, water, and driver and be race ready. Minimum weight will be 2,900 pounds. ACT legal cars may compete at a minimum weight of 2,850 pounds. Maximum left side weight percentage will be 56%.

3-3 DETAILED CAR BODY REQUIREMENTS

3-3.1 Spoilers

(a) Front Spoiler / Air Dam

Minimum ground clearance for front spoiler / air dam shall be 4 (four) inches with driver. Added pieces to the front air dam must be installed in a vertical manner.

(b) Rear Spoiler.

Must be made of .090 minimum thickness smooth aluminum maximum width of 60” wide and 5” high.  Maximum height from ground to top of spoiler 38” for non-ABC bodies.  NO side enclosures no lips or bends in upper portion of spoiler and must be flush to vertical surfaces of deck lid, non-adjustable. 

ABC spoiler heights will be according to instruction manual and will be subject to Five-Star referee inspections.  Measure will from top flat surface at end of trunk lid to ground at 34 x7/8”.

3-3.2 Seat

Driver’s seat must be specifically designed for auto racing and constructed of .125 inch thick aluminum. NO fiberglass seats permitted. Aircraft-quality hardware is required for attaching seat to seat sub-structure as described in diagram section.

3-3.2.1 Seat Location

Seat must be located in such a manner that the inside (left side) is a minimum of 8 (eight) inches distance from the nearest longitudinal door bar member.

3-3.3 Fire Walls

Interior of car must be completely enclosed in respect to engine compartment, track surface, tire wells, and rear, (fuel cell) compartment. The area immediately beneath (floor) the driver and the vertical panels surrounding the seat area, front and rear fire walls, and transmission tunnel MUST BE CONSTRUCTED of minimum 18 gauge steel (.047 inch) and be of welded construction. Other interior panels may be constructed of aluminum, minimum of .040 inch thickness. Panel on passenger side of car may be either:

(a) Flat projecting across at approximately the height of the transmission.

(b) Dropped back to level of floor on driver’s side of compartment. No vertical section of the driver’s right may be higher than the nominal height of the transmission meaning a "boxed" or flat interior section to the driver’s right is not permitted except at transmission height.

3-3.4 Hood and Deck Lids

Hood and trunk lids must have positive pull pin type fasteners. Hoods must have four pin fasteners on leading edge. Rear deck lids must be hinged or easily removed. Rear deck lid may not be riveted to body.

3-3.5 Dashboard

A full width dash is required on all cars. Vertical surface of dash must project in a single plane across the car. Top (horizontal) plane must follow the contour of the windshield between the "A" posts. Instruments must be neatly installed in the vertical panel.

3-4 GENERAL ENGINE REQUIREMENTS

Only Oxford Plains Speedway approved engines permitted. Engines may be interchanged within any corporate manufacturer’s product line. Only ferrous alloy cylinder block type V-8 engines permitted. Camshaft location may not be altered.

3-4.1 Approved Eligible Engines

- GM 350 or 350 ZZ4 package (see below)
- Ford 351 W or 351 SVO
- Chrysler 318 or 360

The limited late model circle track engine P/N # 88958603-GMR-350/355 may be used as shipped from the factory with all seals in place. No alterations permitted.

A ZZ4 GM engine program using the following part numbers and sealed under the direction of the American-Canadian Tour (ACT).

- Crankshaft - 14088533
- Cylinder Head - 10125374 (58 cc)
- Connecting Rod - 10108688
- Block - 10105123

GM Bowtie, Ford SVO, (with the exception of the block and two barrel intake manifold) and Mopar Performance parts are not considered O.E.M. and are not approved for competition. Any other engines must be approved by Oxford Plains Speedway prior to competition.

3-5 DETAILED ENGINE REQUIREMENTS

3-5.1 Engine Location

Engine must be positioned within the chassis per the following specifications in all COMPETING cars.

(a) Cross (lateral) location - centerline of engine crankshaft shall be located within ½ inch of an imaginary line through the center of the car, defined as the dimensional center of a measurement across the car, from the outer most point of wheels.

(b) Front-To-Rear Longitudinal location of the engine (setback) is defined as the engine must be placed with the center of number one spark plug or center of hex if angle fitted even with center of grease fitting on upper ball joints.

3-5.2 Engine Overbore

Maximum overbore size permitted is .040 inches. Stock stroke must be maintained.

3-5.3 Piston / Rods

Aftermarket racing type pistons permitted. Must be flat top with stock pin locations. Two valve reliefs permitted. Aftermarket racing type wrist pins permitted. Floating wrist pins permitted. Connecting Rods must be of stock length and configuration. No billet, aluminum, titanium, or carbon fiber rods permitted.

3-5.4 Crankshaft

Crankshaft must be O.E.M. type steel or cast. No lightening or knife edging permit ted. Balancing permitted.

3-5.5 Oil System

Any wet type system permitted. Oil pump must be located in oil pan. No dry sump systems permitted.

3-5.6 Cylinder Heads

A maximum of 11:0 absolute compression ratio on all engines permitted. Engines will be checked with Whistler machine and/or torn down. 11:1 compression ratio will be considered illegal. No aluminum heads permitted, and must be O.E.M. castings. All heads must have legible casting numbers. No porting, no polishing, no painting, no angle milling permitted. Bottom valve seat cut not to go down more than 5/8 inch.Valves may be aftermarket, but must be stock O.E.M. size. No titanium valves permitted. Seats may be used for repairs only.

3-5.6.1 Maximum Valve Size

Intake Exhaust

GM 1.940 inch 1.500 inch

Ford 1.842 1.540

Chrysler 1.880 1.500

3-5.7 Camshaft / Valve Lifters / Rocker Arms

3-5.7.1 Camshaft

Any steel hydraulic or mechanical camshaft approved by Oxford Plains Speedway permitted. No roller cams permitted. Cams must be chain driven. No gear or belt drives permitted.

3-5.7.2 Valve Lifters

Solid lifters permitted. No roller lifters permitted. No mushroom lifters permitted. Lifter bores may be bored or re-bored and sleeved.

3-5.7.3 Rocker Arms

Roller rocker arms permitted. Adjustable rocker arms permitted. Screw in rocker studs permitted. Rocker arm stud girdle may be used. No shaft type rocker systems permitted on non-Mopar models.

3-5.8 Engine Height

Centerline of crankshaft harmonic balancer (or equivalent) must be located a minimum of 11 (eleven) inches above the ground plane

3-5.9 Intake Manifold

(a) Chevy: Aluminum Edelbrock # 2101 or #2116

(b) Ford: Aluminum Edelbrock #2181. May also use the SVO two barrel intake.

(c) Dodge: Aluminum Edelbrock # 2176

(d) Stock two barrel cast iron intake manifold, no Brezezinski intakes permitted.

3-5.10 Carburetor

Only #4412 Holley 500 CFM carburetor permitted. Absolutely no material may be added or removed from carburetor, except bolt-on choke mechanism.   Canton P.N. # 85060 is the only carburetor spacer allowed.  NO MODIFICATIONS TO THE SPACER ARE ALLOWED.

3-5.11 Air Filter / Air Cleaner / Air Intake

No carburetor hats or air deflecting devices permitted. Air filter housing and fresh air box only. Induction must be from the cowl area. No forward facing or "ram" air type induction is permitted.

3-6 ENGINE ELECTRICAL SYSTEM

3-6.1 Ignition System

Stock or OEM replacement ignitions only. No magneto or twin fire ignition systems permitted.  ACT MSD box will be the only MSD allowed.

3-6.2 Starter

Starter must be in working order and in stock position.

3-6.3 Battery

The battery must be securely mounted and covered. Battery may not be located in the driver’s compartment

3-6.4 Electrical Safety Switch

Car shall be equipped with a safety switch that will effectively kill the power from the battery to the car’s ignition system. Switch must be mounted within reach of the driver’s side window opening.  Alternators must be driven off the front of the engine.

3-7 ENGINE COOLING SYSTEM

Radiator must be located in the stock position and an overflow protection system so as not to discharge fluids directly on the race track. No antifreeze permitted. A cooling additive may be added.  No electric fans may be used.

3-8 ENGINE EXHAUST SYSTEM

3-8.1 Exhaust Manifold

Exhaust headers permitted. All four tubes from right and left bank of engine must enter single collector on each respective side of exhaust. No balance tubes permitted. Must be made of mild steel, no stainless steel permitted. Two mufflers are required and must be Howe #3002 or Magna Flow #11219 and steel pipe must extend beyond driver’s seat and may not be cut or modified and must be installed in correct flow direction.  Maximum exhaust pipe size is 3 ½ inches. No "Two-in-One" or scavenger exhaust systems permitted. Exhaust pipes must go beyond the driver. 

3-9 DRIVE TRAIN

No carbon fiber or titanium parts permitted.

3-9.1 Clutch

Stock clutch with one clutch disc and one pressure plate only. No lightening of clutch disc or pressure plate permitted. No aluminum pressure plates permitted.  ACT cars see ACT rule 22.8.

3-9.2 Flywheel

Flywheel must weigh a minimum of 16 pounds.

3-9.3 Bell Housing

It is recommended that a steel scatter shield be used to cover the top half of the bell housing. Shield may be a steel plate to cover original bell housing and may be attached to the floor boards. A 2 (two) inch inspection hole must be drilled into the bottom of the bell housing for viewing purposes.  Aluminum bell housing will be allowed with ACT clutch And ACT crate engine.

3-9.4 Transmission

Transmission must be stock 3 (three) speed or stock 4 (four) speed standard transmission. No automatic transmissions permitted. Shifter linkage may be one or two rod. All gears must be in working order.  Stock 3 speed to run with ACT weight brake.

3-9.5 Drive Shaft

Only steel drive shaft permitted. It is mandatory that 2 (two) 360 degree brackets, no less than 2 (two) inches wide by 1/8 inch thick, be placed around the drive shaft and fastened to the floor or cross member to keep the shaft from becoming dislodged and falling out. All drive shafts must be painted white.

3-9.6 Rear End

Rear ends must have floating type bearing and hub such as quick change or non-quick change, or front load quick change or steel housing type 9” floater.  With steel center section gear carriers only allowed.  No cambered rear ends permitted. Must be driven with solid flange drive plates.  All running gear drainage plugs must be safety wired.  No titanium parts allowed. 

B: Rear ends may be locked or open no gold traks or any type of ratchet or limited slips allowed.  SPOOLS ONLY.  

3-9.7 Wheels

Aftermarket 8 (eight) inch steel racing wheel required. Bleeder valves permitted.  Front wheels must maintain the same offset left and right. (rear also) Maximum1 (one) ½” spacer per wheel.  Lightening of wheel not allowed.  Must be “out of box”

3-9.8 Tires

Only Oxford Plains Speedway approved tires permitted. Oxford Plains Speedway reserves the right to specify tire manufacturer and type for all events. Refer to Rule 1-38 for the Oxford Plains Speedway tire policy.  Tire clean up with scraper blades only no steel brushes or any form of liquid to clean tires allowed.

3-10 CHASSIS CONSTRUCTION

5-10.1 Center Section Components

Main frame rail structure of chassis, defined as the primary structure to which roll cage members, major suspension components, engine, etc, mount to must be constructed of a mild steel shape having a minimum perimeter dimension of 10 (ten) inches, 2 x 3, 2 ½ x 2 ½, etc.

Main frame members shall be a minimum of:

10 inch perimeter tubing .120 inch wall thickness

12 inch perimeter tubing .095 inch wall thickness

16 inch perimeter tubing .083 inch wall thickness

3-10.2 Front and Rear Section Components

Sections extending such as front and rear clip sections must be a minimum of 10 (ten) inches in perimeter and have a minimum of .083 inch wall thickness and extend 10 (ten) inches beyond wheel base. 10 (ten) inch perimeter tubing must go to the rear edge of the fuel cell.

3-10.3 Perimeter Chassis Defined

A perimeter chassis is defined as having left and right main frame rails that are symmetrical, (with one inch tolerance), with kickout from front clip to main frame rails the same on both sides. Both frame rails must be constructed of steel with some size tubing on both left and right side frame rails and must measure a minimum of 56 inches from outside edge to outside edge. The maximum offset allowed is 1 (one) inch measured from the center line of the tread width.

No straight frame rail cars permitted, unless approved by OPS and with an added weight penalty imposed.

3-10.4 Ballast Weight

Ballast weight must be securely attached to main frame rail or major cross member structure. It is strongly recommended that major ballast weights be contained inside the main frame rails. No lead shot or liquid type ballast permitted. No ballast adjustment devices permitted on car. Weight transfer devices of any type may not be activated by the driver.

3-11 SUSPENSION

3-11.1 Springs

All springs must be minimum 5 inches diameter, if not running coilover, and must be made of steel. Magnet must stick to spring. Coilovers permitted. Spring rubbers will be allowed but must be wired in place. 

3-11.2 Shock Absorbers

Shock rules will be uniform with ACT rules, which are as follows:

KONI brand approved. Recommended models are KON30-7436 and KON30-9325. KON30-7325, KON30-9436, KON30-7647 and KON30-1309 also permitted. No changing or altering valving in eligible shock numbers.

Shocks must not be painted, and model numbers must be fully legible. 

There will be no rebuilding of existing, "old" KONI shocks that might be in current inventory. There are no cross-reference shocks from past years that will be acceptable.   

Shocks may be swapped at any time with ACT/OPS inventory.

3-11.3 Sway Bar

Aftermarket sway bar only allowed. Must be solid bar side to side.

3-11.4 A-Frames

Any stock or aftermarket upper and lower control arms allowed. Lower control arms must be same length left and right. Measurement will be from center of mounting point to center of ball joint. Heim joints permitted.  No lower control arm bump stops allowed.  No chains permitted.

3-11.5 Spindles/Hubs

Any steel spindle allowed. Removable steering arms must be made of steel. Any steel or aluminum safety or racing hub allowed. 5 x 5 or Wide 5 bolt pattern allowed.

3-11.6 Tread Width

All cars must not exceed maximum allowable tread width, front and rear, of 64 ½ inches, measured at the center line of the wheel, zero toe-in, at spindle height.

3-11.7 Wheel Base

Minimum allowable wheel base shall be 104.5 inches.  Maximum allowed shall be 105.5 inches.

3-11.8 Rear Suspension

Truck arm or three-point rear mounting suspension allowed. Solid tubular pannard bar only. One bar with two adjustable heim joints only. No aluminum truck arms. No fifth coils. No Watts linkage.Trailing arms must be solid and of equal length. Rubber mounts must be used. No torque arms permitted. No devises to mechanically transfer weight while car is in motion permitted.  Rubber snubber allowed on rear trailing links.  One upper link pivot with rubber bushing allowed.

3-11.9 Roof Height

Minimum roof height shall be as per. Template sheet measurements or ABC referee.

3-11.10 Frame Rail / Body Component Ground Clearance

The minimum ground clearance from the lowest point of the car, (frame, body, or attached weight, etc.) shall be 4 (four) inches with driver in car.

3-12 STEERING

Any type of front steering allowed. Steering box or rack and pinion are permitted. Power steering pumps must be driven from the front of the motor by belts. Steering columns must have a minimum of two U-joints. Removable steering wheel is required.

3-13 BRAKES

Four wheel steel component brakes in good working order are mandatory. Front brake rotor must be a minimum of 1 (one) inch thick and made of steel.  Rear brake rotors must be a minimum of ¾” and made of steel.  ACT cars must run brakes under rule 19-13 of ACT rule book.

3-14 FUEL/FUEL SYSTEM

Only Oxford Plains Speedway approved fuel may be used.

3-14.1 Fuel Cell

Fuel cell is mandatory and must be approved by technical inspector.  Minimum 15 gallon capacity required.  22 gallon fuel cell maximum.  It is mandatory that the fuel cell be enclosed in a 20 gauge steel welded box.  With a bolt on cover constructed of 20 gauge steel.   Must be protected on back and sides by .095 1-3/4” O.D. tubing.  Fuel cells will be no less than 14” from the centerline of rear axels to front of the fuel cell.  Minimum ground clearance from the bottom of the fuel cell to the ground plane is 8” with the driver in the car.

3-14.2 Fuel Pump

No electric fuel pumps permitted.

3-15 GENERAL SPECIFICATIONS

3-15.1 Roll Bars

All cars shall be required to have a four-point rollcage structure of minimum 1 ¾ inch outside diameter, DOM or seamless .090 inch wall thickness molyendum or mild steel tubing. The rollcage structure shall be fully triangulated with minimum 1/8 inch thick gusset plates utilized at all major tube intersections. The four point rollcage structure shall have a minimum of 4 (four) horizontal driver’s side "door" bars, and at minimum an "X" structure, at least three bars, spanning the opposite side door area between the front and rear roll cage uprights.

Rollcage structure shall be integrated to front frame stub via a "hoop" section surrounding the engine compartment and joining the front rollcage uprights. Rear braces shall extend diagonally from top rear horizontal rollcage members to "kickup" section of rear frame member. Bottom bay of rollcage structure shall have an X-structure spanning between the frame rails. Rear frame section shall have a "X" or oblique members to stiffen frame rails against rear corner impact, lessening parallelogram rollcage tendency of rear rails.

A sub-structure integral with the frame and rollcage members shall provide driver seat mounting points. Foot well area of driver’s compartment must have oblique horizontal member connecting forward upright and main frame rails, then bracketed to engine compartment main hoop.

The 4 (four) point cage shall be symmetrical in all directions. Minimum length for door bars is 42 inches. Total height of rollcage to be 40 ½ inches from bottom of frame. Halo to be no less than 1 (one) inch lower. Width of halo to be no less than 46 inches outside to outside of tubing. Full dashbar required. All cars must have an X-type member across and behind driver. One piece tubing run diagonally or perpendicular between halo in top of cage required. Minimum height of door bars on driver’s side is 22 ½ inches from bottom of frame. Passenger side door bars may be the X’d structure spanning passenger door area. A so called "Petty Bar" must run from center of cage to upper right front halo.

All major rollcage members including uprights, connectors, "door" bars on left or right side, and major braces must be a minimum 1 ¾ inch, .090 inch wall thickness tubing as specified above. Incidental structure components for brackets, components mounting, etc., may be fabricated of lighter material. Full circumference high quality welds are mandatory on all tube connections.

Rollcage material is subject to sonic testing or inspection hole testing for compliance with these rules. A tester for analysis of frame/cage strength may be used repeatedly.

Add 16 gauge metal between door bars and body on driver’s side only. Minimum 40 inches in length and 17 inches high. 16 gauge metal may be welded in between door bars and door bar connectors on driver’s side only.

3-15.2 Additional Roll Cage Specifications for all cars

Roll cage members must CLOSELY conform to window/roof/door contour and not be readily apparent when car is viewed for side area. Rollcage members must be within tube diameter dimensions of actual roof components.

3-15.3 Fire Extinguisher

A working fire extinguisher must be located with reaching distance of the driver and mounted on the right side of the car.

3-15.4 Part Identification Numbers

Any parts that have any identification numbers and those numbers are removed or altered will be declared illegal.

3-15.5 Non-Conforming Parts Penalty

Any parts that are found to not conform to the rules contained herein will become the property of Oxford Plains Speedway and must be surrendered immediately upon demand. Parts will be held by Oxford Plains Speedway and will be disposed of at the desire of Oxford Plains Speedway. If any team refuses to turn over any requested part or parts then that team will be denied access to Oxford Plains Speedway until such parts have been surrendered to the satisfaction of Oxford Plains Speedway management. An additional fine may be imposed as part of the penalty.

3-15.6 Declaration of Intent

Anything not specifically covered in this rule book must be approved for competition by the Technical Director.

3-15.7 Eligibility

A competitor who competes in 5 (five) or less features in a given division in a given year will be eligible for future rookie status.

IT IS THE RESPONSIBILITY OF THE COMPETITOR TO OBTAIN AND BECOME FAMILIAR WITH THE CURRENT RULES PERTAINING TO THE DIVISION IN WHICH HE/SHE CHOOSES TO PARTICIPATE.

The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing to establish minimum acceptable requirements for such events. These rules shall govern the conditions for all events, and by participating in these events all participants are deemed to have obtained and read, and understood a copy of the current rules, and complied with these rules.