full width of bumper. Bumper must have no sharp edges.
REAR BUMPER
Must be made of round steel tubing only, with a maximum diameter of 1 1/2"
by .095' wall thickness for main bumper and all bracing. It must consist of two rails, an upper and a lower,
which must have four sockets and horizontal support bars attaching it to the
frame, These rails must also be a minimum of 10' apart and a maximum of 16" measured from top to bottom and maintain that measurement
for a minimum width of 64" or a maximum width of 86". The rear bumper
or any side bars cannot extend past the outside of tire sidewalls on both sides.
It also must have an 18" center measured from the ground up to middle of
bumper. The rear bumper may not exceed 52" In back of rear axle centerline. No V-shaped bumpers, crash
area must be flat and vertical for the full width of bumper. Bumper must have no sharp edges.
RUB RAILS
Must be made of round steel tubing only, with a minimum diameter of 1 1/2"
by .095" wall thickness. All bracing must also be a minimum of 1 1/2"
outside diameter by .095" wall thickness, Maximum wall thickness must be .095" with no solid bars or ballast added Inside.
Rub rails must be outside
of body panels but may not exceed the outside edge of the tires. The exception
is the left rub rail only, which may extend an absolute maximum of 2' outside
the left rear tire sidewall. Rub rails must be rounded with no sharp edges and
bent at a gradual 90 degrees and must protrude a minimum of 6' back in past the body. Rub rails must
be a minimum of 50"iong, end to end. Single bar rub rails only.
FUEL TANK
One fuel tank with a maximum of 22 gallon is mandatory, used for gasoline only.
Fuel tank height will be 12' minimum from the ground to the bottom of the tank.
Tank must be centered Inside of the frame rails and be rectangular or square in
shape on all sides for measuring capacity. Fuel tank must be fully encased in a
steel container with a minimum thickness of 20 gauge. An optional aluminum
container may be used with a minimum thickness of .060". Fuel tank must be
fully foamed with a minimum cut out for filler. Cut out may be no more than 6' wide by 10" long by 7" deep. Fuel lines must siphon from top only,
No fuel lines bigger than #10. No auxiliary tanks. No fuel filters with more the
1/2 quart capacity. Fuel tank vent line must have an inline one way valve for the prevention of fuel spillage. Only one carburetor fuel log will be allowed
and is limited to a maximum outside diameter of 1'.
MUFFLER
Muffler is not mandatory. If one is used the exhaust must exit past the driver
and must be directed to the rear of the car.. No pipe may face outside the car.
Any manufacturer of exhaust header is allowed, but header material is limited to
steel or stainless. No crossover pipes are permitted connecting the two banks of
cylinders.
BALLIST WEIGHT
Any ballist weight must be mounted within the vertical planes formed by the
frame rails, must be securely
fastened, and must remain stationary while racing.
OILING SYSTEM
One oil cooler, and one passenger car size battery will be the only exceptions
allowed to be mounted outside the
frame rails.
TIRES AND WHEELS
Will be allowed to run any tire or any steel or aluminum wheel, up to and
Including 92". Beadlocks allowed. No plastic wheels. Maximum tire size will
be 29"x 11" The right rear tire softness will be 38
American Racer minimum.
WEIGHT
weights are taken with driver and no fuel added after race is finished. Must
weigh 2500 lbs. Track scales will be
the official scales.
SPORTSMAN ENGINE-SPECIFICATION
This class is reserved for North American passenger car V-8 engines with cast
Iron blocks and cylinder heads. All engine parts must have casting or part numbers
on them for Identification. All engines must maintain stock bore and stroke
combinations.
Engine Maximum Overbore
Chevy 350 ci., 4.00" bore x 3.480' stroke +.070"
Chry 360 ci 4.00" bore x 3.578' stroke +.0200
Chry 340 Ci 4.04" bore x 3.313' stroke +.0600
Ford 351 ci 4.00" bore x 3.5' stroke +.0601
A 4 cu. in. wear allowance is allowed for all manufacturers
Engines must remain stock as manufactured with the following exceptions,
May run a sealed 602 crate, Following the DIRT rules.
BLOCKS
The engine block and all internal parts must meet stock specifications for Its
make. No Bowtie or other performance type blocks allowed. Dart *LittleM"
sportsman block, part #3115111 is allowed.
CYLINDER HEADS
Cast iron OEM stock production heads or 180/200 DART Iron Eagle heads, straight plug or
angle plug),-only. Chevy bow-tie, Chrysler
W-2, and Ford performance heads are allowed providing they