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Official 2008 Hobby Stock Rules






All equipment is subject to approval by South Texas Speedway track officials. Any alterations or modifications from OEM (stock) not specifically allowed in these rules will be considered illegal.

It is the racer’s responsibility to keep his/her car legal at all times. Equipment having passed through inspection unobserved will not be considered as approved. South Texas Speedway officials may assess weight penalties for cars and/or parts deemed as not in compliance with these rules.

It is ultimately the obligation of each participant to insure that their conduct and equipment comply with all applicable rules, as they may be amended from time to time. No expressed or implied warranty of safety shall result from publication of, or compliance with these rules.




Any American made passenger car. Full sized cars with a minimum Wheelbase of 108" + or - 1". Ford Thunderbirds, El Camino's, and Ranchero's o.k. No station wagons, or front wheel drives.

Tubular rear clips are allowed. Front clip must be stock.

*A full frame car is considered any car that has stock frame rails from front end to the center of the rear end housing. If you have questions ask track officials.




All glass must be windshield must be replaced with a minimum 4 bars in front of the driver spaced equally not more than 6 inches apart.

All the following must be removed: carpet, mats, seats, all chrome trim inside and out, headliner, all plastics and any sharp objects.

Hood, fenders, trunk and interior may be gutted.

Replacement of OEM (stock) doors, front fenders, quarter panels, hood, roof, and rear deck lid with aftermarket body components is allowed.

Fiberglass replacement hoods may be used.

All OEM stock doors must be welded or bolted shut.

An aftermarket nosepiece & tail piece may be used as a replacement for the OEM stock pieces.

Rear spoiler can be no taller than 15 inches and be at any angle.






Four post upright design using minimum 1 1/2" .095 wall tubing, the cage must be welded to the vehicle frame. All welds not saddled must have gussets. No galvanized or screw pipie fittings. Minimum 3 driver side door bars and 2 passenger side door bars. Roll bars must have proper clearance for drivers head and hands. All bars within reach of the driver need to be padded.




All cars must have a window net or the driver must wear arm restaints.




Minimum weight of 3250 lbs, after race, with driver (NO FUEL TOP OFF).

Maximum rear percentage for 3-link suspension cars will be 52%

Maximum rear percentage for Leaf Spring suspension cars and full frame 3 links will be 54%




All added weight must be painted white with the car number in a contrasting color and must be bolted to the frame with two (2) bolts, ½ inch minimum diameter. Must be in block form, not less than 10 lbs. (No Pellets).




Factory manufactured metal racing bucket seat mandatory. (NO FIBERGLASS OR PLASTIC)




Three (3) inch lap belt is mandatory. Both ends of the lap belt must be fastened to the roll cage or frame with high quality minimum 3/8-inch diameter bolts.

Shoulder harness must not be less than three (3) inches wide and must come from behind drivers seat. Ends must be fastened to the roll cage or frame with high quality minimum 3/8-inch diameter bolts.

A center crotch belt must be securely mounted to the lower seat frame at the bottom and to the lap belt at the top. Where belts pass through the seat edges or seat metal, there must be a grommet installed, be rolled, and /or padded to prevent cutting and chaffing of belts. All seat belts and shoulder harnesses must connect at the lap belt with an approved quick release buckle.




Hoosier G60 / American Racer kk704 (G60), or D.O.T. approved street legal tires with the max. size being P 235/60/15 series. No racing recaps, no truck tires or racing tires of any type allowed.

Wheels will measure no more than 8" width bead to bead.

Any Wheel offset.

2 Bead Locks are allowed on the right side only.

Grooving tires is allowed.

Wheel spacers are allowed.




Cutting of springs, heating springs and racing springs are allowed.

After market racing shocks will be allowed. The shocks can have any valving.

Only 4 shocks allowed on the car in any location.

No adjustable shocks allowed.

Twist in spacers, rubber spacers, shims and weight jacks are allowed.

Rear coil spring cars may extend coil spring buckets.

Upper control arm shaft may be offset steel type. Tubular Upper A-arms are allowed.

No coil over shocks, No Aluminum shocks.




3-links must use a solid bar for the 3rd link, No spring or biscuit bars allowed.

Full frame cars will be allowed to use a spring or biscuit bar for the 3rd link.

Rear trailing arms must be a minimum of 15 inches from center of heim to center of heim and can not run up hill more than 5 degrees with driver in car after race.

Rear Coil spring must be mounted on top center line of axle tube.

No aftermarket 4 link or z link suspensions. Stock 4-link OK.

Floaters are allowed.

Rear ends may be locked and posi-trac is allowed.

Panhard bar may not be shorter than 26 inches and must be solid no springs or biscuit bars.

NO J-Bars allowed.

No Aluminum allowed anywhere in or on the rearend assembly with the exception of drive plates and brake hats.




All engines must remain stock for that car (GM to GM, Ford to Ford, Chrysler to Chrysler.)

Engine blocks may be bored for cleanup and repair purposes.

All engines must remain stock stroke. No strokers.

Aftermarket OEM (stock) type steel replacement connecting rods allowed.

No part of the piston may protrude out of the block deck surface.

Flattop or dished pistons only.

Maximum engine set back is when #1 plug is in front of or even with the forward most ball joint.




Any Cast iron head allowed. Guide plates and stud girdles o.k. screw in studs o.k.

Any valve spring can be used.

No porting or polishing. No angle milling.

Maximum valve size of 2.02 intake and 1.6 exhaust.

Any length rocker arm allowed.




Any Aluminum intake allowed.

NO porting or polishing allowed.

No gasket matching or porting.




Only steel, hydraulic or solid camshafts allowed.

No roller or mushroom type lifters allowed. Lifter must be of stock weight and size.

Only OEM stock type timing gears and chain allowed. Dual roller chains allowed.

Timing advance or retard bushings allowed. No belt or gear drive systems allowed.




Stock carburetors or Holly 4412 500 CFM will be allowed with no modifications except idle holes may be drilled into butterflies, but only one per side, and may not be larger than 1/8".

A one-piece solid spacer maximum 1 1/8" thick with gasket is allowed to mount 4412.

Choke horn must not be removed.

The choke may be removed but all screw holes must be permanently sealed.




O.E.M. (stock) type cam driven point or electric ignition system is permitted. HEI system may use high performance module and coil.

MSD Ignition systems are allowed.




No tuned 180 degree headers allowed.




Battery must be totally enclosed and mounted securely.

Gel cell or dry type batteries are permitted.




No wet clutch type transmissions.

Transmissions must remain stock style.

Automatics will run stock converters.

No Aluminum flywheels.

Mini-clutches allowed.

Drive Shaft must be steel and painted white.




4 Wheel brakes are mandatory and must be functional at all times with no modifications.

Aftermarket style brake pedals, master cylinders, and bias adjusters are allowed.

Only steel single piston calipers will be allowed.

Caliper may not be lightened or altered in any way.

Rear brake drums must be stock.




Pump gasoline, racing fuel or Methonal allowed.

No nitrous oxide allowed.




All fuel cells must be of steel construction.

No plastic tanks unless enclosed in steel.

Car must have a fuel cell protection loop for impact protection.

Fuel cell must be securely mounted to rear frame.

Fuel cell must be mounted as far forward as possible and be centered on the track width.




Fire extinguishers are recommended in the drivers compartment within the reach of the driver. The driver must be able to reach the extinguisher when buckled in the seat and the extinguisher must have an operating gauge.




Officials reserve the right to make final decisions in the interpretation of any rules or race procedures at any time. No equipment will be considered as having been approved by reason of having passed through inspection unobserved.

If you have any questions regarding the rules set forth, contact Owen Pittman at 361-548-0669.

We reserve the right to make adjustments in total car weight.

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Rear trailing arms must be 15" in length and not run uphill more than 5 degrees.



Is that 15" from the center of the heim to the center of the other?


5 degrees when the car is sitting at race height?


How about rear spoiler height?


Tire grooving still OK?


How about Hoosier g-60's?

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