2010 Pure Stock Rules
Acceptable automobiles, any North American full or mid size rear
wheel drive vehicle, including sports cars (Firebird, Camaro, Mustang, or Trans
Am). The vehicles not allowed are Jeeps, sports utility, and rear/mid engine
Bodies must remain stock appearing with doors welded shut. All composite
material (breakable plastic nose and tail) must be removed. After market nose and
tail pieces, one or two piece nose or tail will be allowed. No sharp edges are
permitted. The car must have a stock appearing front and rear. Push bars front and
rear will be permitted outside body panel, but must not extend beyond the vertical
plane of the bumper. Tow hooks front and rear are mandatory. Steel floor boards
and fire wall must remain stock appearing with a transmission tunnel and holes
must be patched. A rear fire wall must be installed. 5” Rear deck spoilers are
3. Roll cage:
A four post roll cage securely fastened to the frame, with a minimum of
three bars on the left and two bars on the right. The roll cage must form an X
behind the driver’s seat. Roll cage must form a box, at a minimum of 4” above the
driver’s helmet. A bar following the contour of the windshield must be placed in
the center of the windshield area along with a bar running front to rear of the cage
in the center above the drivers compartment. All joints must be completely welded.
Rolls bars must be a minimum of 1 1/2” in diameter and .095” thick. Exhaust
tubing will not be allowed. Cars with roll cages bolted or welded to the floor
boards will not be allowed on the track. Front hoops and rear hoops are permitted.
Only a racing approved seat must be installed, and mounted to the cage and frame.
No plastic or bucket seats will be allowed.
4. Engine/Drive Line:
Carbureted motors only, fuel injection motors must
be converted. Engine must remain completely stock with stock non hiperformance
parts, and in stock location. Carburetor may be stock
quadra jet 4 barrel. A 2 barrel holley 500 c.f.m. with a 1” adaptor will
also be allowed. Hi rise intakes will not be permitted.. No angle plug
heads. Double hump heads are permitted. No porting or polishing or
gasket matching of the intake or heads will be permitted. Only a stock
cast iron 4 bbl. Manifold ,E.G.R. type will be allowed. Only stock cast
iron under spark plug type exhaust manifolds allowed . 2-1/2” OD
exhaust pipe to exit behind the driver. No roller cams, or roller tipped
rockers allowed. Stamped rockers only are permitted. Engines are permitted to be
bored to a maximum of .060 oversize, Stock cast iron crank shafts only. Stock
connecting rods with a stock length. Pistons may be flat top or dished only, no
raised dome pistons will be allowed. Stock ignitions systems only. All cast parts
must have there o.e.m. factory part numbers on them. Displacement
allowed before maximum over bore will be GM 350 c.i. , Ford
351 c.i. Chrysler 360 c.i.
Hi performance OEM parts not permitted. Clutch must be stock with a stock steel flywheel and
pressure plate. Steel scatter shield must be used. Any standard stock transmission will be
permitted. Torque converter must be a working torque. No lock up valve permitted. A drive shaft
hoop must be installed and drive shaft must be painted white. Rear axel must remain stock, and in
stock location. Ford 9” will be permitted with stock mounts and in stock locations. Spiders may be
welded or a spool may be installed.
5. Wheels and Tires:
Steel racing wheels allowed, with a maximum of 8”wide X 15”diameter and a
maximum a 2” offset. No aluminum or magnesium wheels allowed. Wheel bead area may be
reinforced. All wheels must accommodate 5/8 oversized studs. All axels and hubs must be drilled
and oversized studs and lug nuts are required. Bead-lock wheels will be permitted on all corners
. Racing tires will be permitted up to 8” wide. Recapped and non recapped passenger car tires will
be permitted also, but no winter tread pattern will be allowed.
*Screwing of tire beads will not be allowed.
Car and driver must weigh a minimum of 3300 lbs. after any race. Any extra weight
ballast must be securely fastened and painted white with car number on it.
All cars must have four working stock type brakes. No brake shut off devices will be
allowed. Emergency brake may be removed.
Fire extinguisher must be installed with in sight and reach of the driver and track personnel.
No fuel lines are permitted in driver’s area unless completely encased in metal tubing with both
ends exiting past driver’s area. Only racing fuel cells with metal enclosure are permitted and must
be located in the trunk area of the car. Full windshield screen and window nets are mandatory. 3” seat
and shoulder harness are mandatory. Belts must be bolted to cage and or frame. No frayed or
torn belts will be permitted; any car found with such will not be permitted on track surface until
replaced. Batteries are not permitted in driver’s compartment area. All cars must have a front
9. Racing fuel will be permitted.
** Changes for the 2010 season are in red
**All cars are to be clean and in presentable condition for each race**
** If the rules don’t say you can, you can’t**
**In the event of a conflict between the class rules and the speedways general
And safety rules, the speedway rules take precedence.**
**Any cars found deficient in the above stated rules will only be permitted to
run at the discretion of the track safety/tech personal**
**Thunder Mountain Speedway reserves the right to make changes as needed to
equalize the division**