Winchester Speedway

 MODIFIED STOCK RULES

1. No high performance parts allowed except as stated.

2. Wheel base 108.

3. Stock suspension - Aftermarket “A” Frame on top side only allowed, . Lower “A” Frame must be stock for the car that it is on.oem spindles only. Leaf spring cars - shackles only, blocks allowed.

4. Engine - #1 plug even with ball joint max setback.

 Bore and Stroke

     A. Stock bore - +.060 maximum.

     B. Stroke - Stock for CID of engine. Crankshaft may be aftermarket, must be stock appearing, and weigh no less than 48lbs.

     C. Rods - Must be stock length for CID of engine.

     D. Pistons. Flat top no gas ported. No less than .062 ring landings. The weight for rod ,piston ,ring, pin and bearings must not be less1300 grams.

     E. Camshaft - 480 lift Hydraulic or  flat tappet cam only. Roller rockers are OK.  Factory ratio  

     F. Carburetor - Gas only. 750 Holley Max. 200 lb. weight break. 600 Holley single line stock part # 080457.

     G. Intake - Any aluminum. Max 1” adapter or spacer plate. No porting or polishing.

     H. Compression - 180 # maximum. Will be checked with all plugs removed and throttle wide open until needle stops.

I. Heads - Stock heads and S/R heads. Must be stock diameter valves for CID of engine. Small Block Chevy 1.940 intake, 1.500 exhausts. Small block Ford 1.940 intake, 1.600 exhaust. May be aftermarket valves:solid steel only . Valve springs must be stock diameter. No porting, polishing, grinding, etc. May have pinned or screw in studs and guide plates. Three angle valve job permitted. 170 cc. Runners max and combustion chamber must be equal to factory

     J. Ignition - MSD boxes allowed. Distributor type or CD(Capacitive Discharge) Ignition systems only.

     K. Rings, Rod & Main Bearings, Oil pumps, Cam and Lifters, valves, valve springs, gaskets, plugs, plug wires, push rods, bolts, nuts, etc. may be aftermarket.

     L. May run aftermarket oil pans.

5. Rear End - Locked rear ends only.  Any factory type rear end. Must be mounted with stock replacement brackets for the car that it is under Southwest Speedway or equal. May be floater axle. May use rear disc, calipers and hubs, must be same as factory.   (Example: front GM can be used on rear.) REAREND must be in factory stock position, no trailing or leading. Mounting points shall be the same as the factory for the type of car that the rear end is being used under. Top trail arms maybe shortened for pinion angle, must be the same length, no hemi joint allowed in trailarms After market must be equal to stock in length  and bushins Non adjustable .

6. Transmission - straight shift legal. Must have all gears and be produced by manufacturer of car. Automatics must have working torque converter.  Functional torque converter.

7. Clutch, pressure plate, and flywheel must be steel factory type. Minimum weight of 34lbs with no tolerance. No modifications.  May be aftermarket. 10 ½” minimum diameter clutch. 

8. Shocks- Rebuildable Steel Shocks Legal.  A) Catalog Price not to exceed  $125. Shock protest. $150.00, Track retains $150. Any shock not conforming per factory specs will be disqualified. Owner will forfeit shocks and be fined $300 Protesters money will be returned. High dollar shocks will not be allowed in this class. 

9. Safety Hub RF.

10. Wheels - 10in steel wheel max. Bead Lock allowed on right rear and right front.

11. Tires - no racing or recapped tires. 275 x 60 maximum. No chemicals allowed.

12. Bodies - Must be full bodied cars or trucks. Top, hood, and deck lid must be original or aftermarket and must be stock appearing.

     A. Quarter panels, doors, and fender may be made of aluminum but must be made in separate pieces and be stock appearing.

     B. Tubing may be used to tie sub frame together at factory location, parallel only.

C. 8 in. rear spoilers and side spoilers .

13. Weight - 362 and under is 3200 lbs. Greater than 362 CID is 3500 lbs.

14. Fuel tanks - a mandatory firewall between driver and fuel tank.

15. Headers - legal.

16. Frame section in front of A Frame mount and behind rear suspension mounts may be replaced with tubing due to rust or excessive damage.

17. All glass and flammable parts must be removed.

18. Roll bars - All cars must have a 4 point roll cage. 4 bars on driver’s side, 2 in passenger side (1 ½” minimum OD black pipe.)

19. 1” diameter lug nuts minimum. Must have 5 lug studs and lug nuts per wheel

20.ANY TIME IN DOUBT ALWAYS ASK.

SOME TYPE MUFFLER IS REQUIRED,

For WINTERFEST Only: Along side Winchester Speedway Regular Modified Stock Rules, also being allowed for WINTERFEST ONLY: Light Weight Clutches & Bert Transmissions will be Allowed, but MUST ADD 50 LBS next to the ENGINE. Normal Weight - 362 and under is 3200 lbs. Greater than 362 CID is 3500 lbs. With the Light Weight Clutch or Bert Transmission Weight - 362 and under is 3250 lbs. Greater than 362 CID is 3550 lbs

Updated 3/26/14

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