2010 Hobby Stock Rules

Notice: All components are subject to inspection and approval of Track Officials. No equipment will be considered as having been approved by reason of having passed through inspection unobserved. ALL RULES WILL BE INTERPRETED BY TRACK OFFICIALS. IF YOU HAVE ANY QUESTIONS ABOUT RULES, CALL BEFORE BUILDING CAR.

DRIVER RESTRAINT:

1. Aluminum racing seat is required, with rib supports is recommended. Seats must be securely mounted to chassis, not floor pan, with a minimum of four 3/8" bolts. Seat may not be positioned further back than doorpost.

2. 5 point safety harnesses are required. Required: S.F.I. tag must be legible. Must be bolted to the roll cage and frame with a minimum bolt size of ½ inch bolts.

3. A window net is mandatory. No sprint car nets.

4. All helmets must be a full face, current Snell 90 or newer sticker in it. Snell SA90 & SA00 legal.

5. All drivers are required to wear a driving suit. No nomex coveralls will be allowed. Neck brace is mandatory for drivers. Driving gloves and driving shoes are required.

Minimum weight allowed is 3200 lbs after feature race with driver in car. Any ballast added to the car must be painted white with the car number on it and must be securely welded or bolted to the frame. No tie straps may be used. With Ford 9” the car will be no less than 3300 lbs with driver for will be deemed illegal. NO Exceptions!

Any U. S. manufactured 1960 or newer stock passenger cars will be allowed. Frame, body and engine must be stock for make. Minimum factory stock wheelbase allowed is 108”. All frames must be absolutely stock. NO Camaros, Firebirds, and Mustangs will be allowed.

The body must be stock with no modifications. All plastic, chrome, glass and interior must be removed. All taillight, headlight, and parking light assemblies must be removed. Cars must have full metal stock front and rear firewalls, full stock floorboards, & rocker panels; trunk and rear fender wells. Doors must be welded or bolted closed. All welds must be complete with no tack welding allowed. No hood scoops. Aftermarket OEM-appearing noses are allowed. Screen supported by 3 vertical bars must be on driver’s side of windshield. Full screen is recommended. Rear of car must be completely sealed, including covers for taillight assemblies.

Spoiler max height is 6” and must be attached to trunk only.

A steel roll cage is mandatory. Front and rear cage-type roll bars must be connected at the top. At least 3 left side door bars and 2 right-side door bars are mandatory. Also, proper bracing and triangulation on front and rear roll bars required. Minimum size allowed for all tubing is 1 ½” O.D. x 0.120 thickness or 1 ¾” OD x 0.095 thickness. Doors may be gutted for sidebars. A front loop extending from the roll cage forward to protect the radiator is allowed, but must be no wider than the front frame rails. The loop may be braced to the frame. Rear loop is allowed, but not wider than the rear frame rails. It may be braced to frame rails.

A single nerf bar is allowed on each side. Maximum size 1.5” x .095”. May be attached to main cage only at the front and rear section of the nerf bar. This means only two (2) attachment points are allowed. No open tubing allowed. Tubing must be capped or rounded with no sharp edges. Nerf bars are allowed on the rear outside quarter panel area. Nerf bars may not extend outside of tires.

Front and rear bumpers required. Stock or fabricated will be allowed. No sharp edges. Front bumper may not extend beyond inside tire width except cars with nosepieces. Fabricated bumpers may be no more than 1.75" ODx.125 wall round tube or 2x3x.125 wall rectangle. Fabricated bumpers must be capped at ends. All cars must be equipped with tow hooks or a small chain loop, front & rear, easily visible and accessible for quick hookup.

Cast iron block only. Maximum engine size is 364 cubic inch. Aftermarket stock appearing connecting rods and cast crankshafts are allowed. Minimum crankshaft weight 51 pounds. Polishing of connecting rod beams is not allowed. Connecting rods must be of press fit type; no floating pins. No 400 cid blocks allowed. Must retain stock stroke for engine type (i.e., 3.48 inch for GM). Flat top or dished pistons only; four valve reliefs per piston required. No camshaft gear drives allowed. Unaltered, stock cast iron intake manifold required. No "marine", "bowtie" nor aluminum manifold allowed. Compression Rule 180 lbs. on 5 hits of starter.

May be in stock location or #1 spark plug can be even with ball-joint or forward. #1 spark plug may not extend behind upper ball joint on any car.

FORD ENGINE: 289, 302 or351 CID blocks only. Any cast iron OEM head is allowed. No after market or Boss head is allowed. Must follow same machining procedures shown below, for GM heads.

Any open chamber cast iron OEM factory production straight plug cylinder head is permitted, with the exception of factory high performance type heads. No Vortec

Heads. Most common allowable casting numbers are 882,487,993 and 441. No closed chamber heads allowed, such as ….461 and …465. Valve size is limited to 1.94-inch intake and 1.50-inch exhaust for GM. GM 305 heads are the only exception allowed, however, intake valve cannot exceed 1.84-inch diameter, and exhaust valve cannot exceed 1.50-inch diameter. OEM or stock appearing after market rocker arms allowed. No roller tip rocker arms or rocker arm stud girdles allowed. After market style rocker arm lock nuts are permitted. Push rod guide plates are permitted. Rocker arm studs may be pinned or screw in type. Any single valve spring, with damper, is allowed. Heads may be flat milled; no angle milling. No porting or polishing. Any work done in the valve bowl area must be done with a 360 degree cut, with the valve guide as the center point.

Hydraulic cam and lifters only. Roller lifters of any type are not permitted. Camshaft lobe lift not to exceed .300 with 1.5 rocker arms or .280 with 1.60 rocker arms. Maximum valve life allowed is .450” measured at the valve.

No fuel injection. GM must run q-jet, or Holley 4412 2 bbl. Rochester 2 barrels also allowed. Ford must run Motorcraft 4 barrel or Holley 4412 2 bbl.

Aftermarket cap, coils, rotor, plug wires, etc will be allowed. No electronic traction control devices. MSD boxes are not allowed.

1. All cars must have an ignition switch clearly labeled.

2. The car must also have a battery disconnect switch located outside the car and easy accessible to emergency personnel. If the car is equipped with a working alternator the switch must disable alternator as well.

3. Only 1 twelve-volt battery is allowed. Battery and box must be securely mounted and enclosed if in driver's compartment or trunk.

Only one radiator may be used. It must be centered in front of the engine in a vertical position. No auxiliary cooling tanks are allowed. Protective loop allowed no taller than radiator and no wider than frame.

Fuel pump must be stock mount push rod activated. Aftermarket manual type pump is OK. (Example: Carter, AC, and Holley) No Pro cam fuel pump.

Racing gas is allowed. No performance additives. No alcohol.

If a stock cast iron exhaust manifold is used, mufflers are not required. Use of headers requires the use of SCE 63030, SCE 83030, or IMCA 609 mufflers. Must register no more than 100 dB at 100 feet. No 180 degree headers allowed.

Front suspension must be A-frame type. Must have OEM hubs (right front may be heavy duty). Heavy-duty shock absorbers will be allowed (one shock per wheel). Front and rear suspension must remain absolutely stock and in original location. Suspension may not be reinforced. No weight jacks. Racing type shocks are allowed but must be stock mount type and in stock location. Racing springs are allowed. Steel IMCA Stock Car A-Arm part #91034394 left/right may be used.

All steering components must be stock and sector must be in stock location (quick steering optional). Quick-release steering wheel is mandatory.

Any OEM automatic transmission is allowed. Unit must be stock and have a full working torque converter, minimum of 10". Powerglides must have 10” torque converter. No direct drives, valved pumps or bleeder style valve bodies. All forward, neutral and reverse gears must be in working order for all automatics except Powerglides. Powerglides are allowed to have either one or both forward gears, with neutral and reverse in working order.

Standard transmissions must be OEM stock, with all gears in working order and a minimum of 10.5” clutch, pressure plate and full size stock flywheel. No mini-clutches or direct drives. Standard transmissions may not use aluminum flywheel of any size.

All standard transmissions must have bell housing made of 1/4” thick steel and must cover 180 degrees over the sides and top of the clutch assembly (also referred to as a blow-proof bell housing).

No 4-speed, 5-speed or 6-speed manual transmissions, no overdrive transmissions or overdrive units. No Bert, Brinn or internal clutch style transmissions allowed. No ram couplers allowed. Quick-change transmissions or transmission adapters for gear change are not allowed.

Car must be self-starting and have working neutral, reverse and ALL forward gears. (ex. 3-speed trans. must have 3 forward working gears.

Transmission fluid coolers are allowed, but may not be mounted exposed in drivers compartment.

Drive shaft:

Drive shaft must be steel and must be painted white or silver. Drive shaft must have a steel drive shaft loop (360 degrees) connected to the frame located within 6” of the front drive shaft u-joint. Minimum size of drive shaft loop is 2” x 1/4” or minimum 1” round tubing. No chain loops are allowed as drive shaft loops.

Rear-ends must be OEM for make and model of frame, with stock length upper and lower control arms for that frame required. Any gear ratio which can be installed without altering of rear-end housing is allowed. 8.5 inch may replace 7.5 inch. Axles must be locked together at all times, with mini spool or weld. No limited slip, Detroit locker nor full spool allowed. Will allow Ford 9” with weight of 3300lbs.

Must have OEM hubs and brakes with a minimum of three (3) wheel brakes in good working order. Four (4) wheel brakes are recommended. Rear disc brakes are allowed with stock calipers. No drilled or slotted rotors.

Only one fuel cell is allowed. The fuel cell must hold at least 6 gallons, but no more than 16 U.S. gallons. Fuel cell must be mounted in trunk area and not visible from the exterior. A protective loop around fuel cell is mandatory Pressure tanks are not allowed on fuel system. If fuel lines are running through the driver’s compartment, they must be inside metal tubing or steel braided tubing. No cast iron fittings may be used. Only fuel type hose may be used for fuel line. Steel braided recommended. Trunk floor may not be removed, but must have a way of letting gas escape, such as drain holes. Use of a fuel cell is mandatory.

60 SERIES D.O.T. Radial Tires only, must be able to have road hazard. Grooved and siped tires are allowed. No softening of tires. Asphalt pulloffs will also be allowed with a durometer reading of no less than 50 after the races. Bleed-off valves may not be used.

Wheels must be steel rims only. Not to exceed 8”. Bead locks are allowed on right side (driver option). All wheels must have a minimum of five (5) 1” lug nuts. No stock wheels on right side.

Numbers on cars must be located on both doors, the roof, and on the back. They must be in a color, which contrasts with the color of the car. Numbers on the doors must be 24” tall and 4” wide. Numbers on the roof must be 28” tall and positioned to be read from the passenger side. Numbers on the back must be 6” for the following driver to be able to read. Numbers with letters are allowed. Numbers must be easily read by scorekeepers to insure proper placing.