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David Gould Racing
* With credit to Rich Hobatuk
SPECIFICATIONS
1) Bodies
a)
Must be fiberglass, metal, or polycarbonate, enclosing a minimum of 70%
of driver’s area.
b)
Engines must be covered.
c)
All cars must have an opening large enough to provide rapid exit of
driver from vehicle.
d)
Side windows must be open and at least 6.5" x 12" to provide emergency
access to cockpit. Body panels must not impair driver’s side vision.
e)
Cars must have a closed roof that can be opened from either the inside or
outside. Roof must be secured with a mechanism that prevents accidental
opening.
f)
Cars must have a recognizable Dirt Modified or Asphalt Modified body
style.
g)
Car numbers must be a minimum of 10" tall and placed on roof and both
sides. All numbers must be legible for scoring purposes and roof numbers must
be readable from the right side of car.
h)
If a track scorer requests a change in your number scheme, you must
comply.
i)
No wings allowed.
j)
Any bars that can strike the driver’s head or torso must be padded.
k)
Large openings must
be covered by ˝” x ˝” screening to prevent debris from entering driver
compartment.
2) Brake
System
A)
Must be foot-operated by pedal.
B)
Mechanical or hydraulic disc brake only.
C)
Both rear
wheels must brake. If brakes are also mounted on front wheels, both must work
together.
3)
Bumpers-
All
welds must be complete: top, sides, and bottom.
a)
All cars shall be equipped with bumpers on the front and rear of the
vehicle.
b)
Bumpers must
be made of 16-gauge (.065”) minimum 3/4" steel, tubular or square stock, or a
minimum of 1" diameter .100” wall thickness aluminum.
Channel bumpers are not permitted.
c)
Must be 3" - 5" from the ground to the bottom of the lowest rail and at
least 6" from the bottom of the lowest rail to the top of the top rail. Must
have a minimum of 3 connecting bars, at least one must be in the center of the
bumper.
d)
The rear bumper must cover the full width of the vehicle to at least
the center of the rear tires, but not to extend beyond the outer edge of
tires.
e)
The front bumper shall be a minimum of 15" and a maximum of 24" wide,
centered between the main frame rails where they attach to the front of the
frame.
f)
All bumper ends must be radiuses or boxed to prevent hooking other
cars.
Exhaust
System
The exhaust system on all cars must be a minimum of 3" from any tire and is
not included in measurements of the overall length of car.
b) The
exhaust must exit to the outside of car body and frame.
4)
Fire Wall
and Flooring
-
A)
All cars must have
a minimum of .030” thickness firewall completely sealing driver from fuel
supply and engine compartment.
b)
All cars must have a minimum of .030” thickness metal floor pan with no
openings between
the driver and ground. The floor pan must cover the complete underside of the
driver’s compartment from nose to behind seat or beginning of firewall, in
order to shield driver’s body from the ground.
c)
Any large openings between
floor pan and body must have ˝" x ˝" screening or protective covering to
prevent track debris from entering driver compartment.
4)
Frames --
All
welds must be complete: top, sides, and bottom.
a)
All frames (chassis) must be made of a minimum of 16-gauge (.065”) 1"
diameter tubular or (.065) 1" square stock, seamless wall or welded wall,
steel or better quality.
c)
Stub axles and axles must be rigidly mounted (bolted or welded) to the
chassis such that there is only UNSPRUNG weight. No SPRUNG weight allowed.
·
Hydraulic or pneumatic shock absorbers
affecting motion of
axles or stub axles are not permitted.
·
A
visual check should reveal no springs controlling rotative axle or stub axle
motion.
d)
All cars must have a footrest or heel stop to prevent feet from sliding
out the nose of the vehicle.
e)
Side roll cage protection must be made of a minimum of 16 gauge (.065”)
˝” diameter tubular, or (.065”) ˝” square stock, seamless wall or welded
seamed wall, steel or better quality. Sidebars must be placed to prevent
intrusion by another vehicle into the cockpit area. All cars must have minimum
of 2 sidebars, placed horizontally, vertically or
diagonally.
Nerf bars can not substitute for side bar protection.
5)
Head Rests
All cars must have a cushioned
headrest mounted directly behind the driver’s head. The cushion shall be
mounted so that it is at the approximate height of the center of the driver’s
helmet. It must be a minimum of 4" x 4”
and 2 inches thick. It
must be within the main roll-cage, as viewed from rear and sides. When in
driving position, the back of the driver’s helmet must rest against the
headrest.
6)
Height
A car may not be higher than 42"
or lower than 32", measured from the ground up (with tires on), to the highest
point.
7) Width
May not be narrower than 37", or
wider than 48", measured at the widest point of the car.
8) Length
A car may not be shorter than
78", or longer than 92", measured from bumper to bumper.
9) Weight
a)
Minimum weight of car after race is 200 lbs. (without driver)
b)
Weight
of car and driver
must be at least the minimum shown in Class Rules.
c)
Removable ballast must be secured to the welded chassis or other part of the
car with bolts and cotter keys/safety wire.
10)
Ignition
Safety Kill Switch
Cars must be equipped with a
safety kill switch that will shut off the ignition for the motor. Switch must
be accessible within driver’s compartment and must be conspicuously labeled ON
and OFF.
11)
Mirrors and Radios
No mirrors or radios allowed in
car.
12)
Nerfing Bars-
All
welds must be complete: top, sides, and bottom.
a)
Must be made of a minimum of 3/4", .065” tubular or square stock steel
(or aluminum of equal or better strength) and have a minimum of 3/4"
over-rider bar welded on top, or a minimum 3/4", .065 tubular or square stock
steel or aluminum of equal or better strength under-rider bar welded on
bottom.
b)
Must extend within 2" of, but not beyond, the outside edge of the tire.
c)
Must be within 4" of the rear tires.
d)
Must be a minimum of ˝ the length of the wheelbase.
e)
Must be welded or bolted securely to the frame.
13)
Oil Catch Can
a)
An oil catch can must be mounted inside the body constructed such that
oil blow-by cannot leak onto the track.
b)
All oil blow-by from the engine breather system must be routed to an
Oil
Catch Can .
c)
The oil catch can must be vented only to outside air. No connection to
carburetor or exhaust system permitted.
d)
The total area of all vent lines from the can must be greater than the
total area of all lines connecting the can to the engine breather system.
e)
Must
not leak oil on track.
14)
Roll-Over Bars -
All welds must be complete: top, sides, and bottom.
a)
All cars must have a roll-cage with sidebar protection. The main
roll-cage must be made of a minimum of 16-gauge (.065) 1" diameter tubular, or
(.065) 1" square stock, seamless wall or welded seamed wall, steel or better
quality.
b)
Roll-cage bars must have steel gussets welded in at the four top main
joints.
c)
All roll-cages must be welded to the main chassis of the car, with
gussets at all welded structural joints as appropriate.
d)
The roll-bar must clear the driver’s helmet by a minimum of 3",
measuring from a line between the top of the roll-bar and the top front of the
roll-cage.
e)
Driver’s head and body must be entirely enclosed within the roll-cage
and car body.
15)
Safety Belts
a)
Cars must be equipped with double over-the-shoulder harness, 3" lap
belt, and sub strap, with a single quick-release.
b)
Belts must be fastened to the frame of the vehicle at both ends of lap
belt, and end(s) of shoulder harness and sub strap.
c)
All fittings and connections on belts must be metal and bolts, if used,
must be grade 5 or better.
d)
“Cam-Lock” type seat releases will not be permitted.
e)
Mounting of over-the-shoulder harness:
16)
Seats
a)
Seats shall be attached to the frame of the vehicle, the roll-cage, or to a
metal plate attached to the frame or base or front of the seat, not more than 4"
from the outside edge of the seat at the two most practical widely-spaced
points, and bolts shall be installed at the two most practical widely-spaced
points at the top of the back of the seat. A metal strap at least 2" in width
shall connect every 2 bolts on the inside of the seat, or be connected directly
to the vehicle.
b)
All
bolts must be a minimum 5/16" diameter.
17)
Steering
a)
Cars must have direct mechanical steering with all axle linkage bolts and
nuts cotter-keyed or safety-wired.
b)
All rod ends must have aircraft quality universal-type swivel joints.
c)
Universal joint steering systems must be welded, except where it bolts to
a rack. Must be secured safely to rack.
d)
Hollow steering shafts must be made of a minimum of .065" steel or better
quality tubing.
e)
Tie rods may be hollow aluminum or steel or solid steel. Solid tie rods
must have a minimum diameter of 5/16" and may have threaded ends.
f)
Tie rods made entirely from threaded rods are not allowed.
1) Tires
and Wheels
a)
Maximum wheel diameter not to exceed 6".
b)
Maximum tire diameter not to exceed 15".
c)
All wheels must be made of quality construction and material approved
for racing competition.
d)
All wheel axles must be cotter-keyed or C-clipped.
e)
Live rear only. No slipper or ratchet hubs -- both rear wheels must be
fixed. Must use all keys.
2)
Wheelbase
Wheelbase may not be shorter
than 52", or longer than 67", measured between the centers of the front and
rear axles.
3) Windshields
a)
Required, made of metal screening with a maximum spacing of ˝" x ˝", or
clear Polycarbonate, covering entire windshield area.
b)
No glass anywhere on car.
4)
Clutches
Centrifugal dry
clutches only (chain only). Quick-change sprockets allowed.
*
State Law and Track Rules set Junior Class Requirements at this time.
†
State Law and Track Rules determine minimum age of competitors.
SPORTSMAN ENGINE SPECIFICATIONS
|
Engines
Allowed
Briggs & Stratton 5
HP, 4-cycle, horizontal shaft only from the following list of blocks:
Raptor I, II & III,
130202, 130232, 132232, 133202, 133232, 13502, 135232, 135230, 133230, 555206,
555205 555168
Only one (1) engine
allowed in car during any race.
Engine Modifications
No alterations of any kind
are allowed to the engine unless specifically stated in this section. Engines
must comply with WKA STOCK 5 HP BRIGGS rules.
1)
Engine Breather System
Briggs & Stratton stock breather
assembly or modified versions may be used. No modifications of any kind to
stock breather hole diameter. Modified breather can be found at most Kart
shops. Breather hose must be connected only to the oil catch can.
2) Balancing
No engine balancing allowed.
3)
Block
a)
Allen screws and stud kits allowed.
b)
Engine girdles allowed.
c)
Governor system may be partially or fully removed. Governor paddle
hole must be plugged.
d)
Maximum engine overbore allowed is .030" plus .010" for wear. Maximum
absolute measurement is 2.6025".
e)
Removal of metal at base of cylinder wall to allow use of heavy-duty
connecting rod is permitted.
f)
Repairs to cylinder block may be made but must be approved by Chief
Tech. Inspector in writing prior to racing.
g)
Deck to piston clearance -- The piston cannot protrude more than .005"
above the block. Machining of deck is permitted.
h)
Repairs to cylinder block are allowed, but must be approved by tech
inspector in writing prior to racing. The written
approval
must be kept and shown to a tech inspector upon request at any race.
4)
Carburator
a)
No visual tech on carburetor bore,
but .695” maximum bore.
b)
Must comply with WKA Tech Rules with exception of pressed-in plug on
outside end of Briggs carburetor, which may be removed.
5)
Crankshaft
Stock OEM cast crankshaft, stock
stroke of 2.4370" + .010".
6) Exhaust
Any exhaust system allowed (must
pass state and track requirements). WKA RLV-91B muffler.
7)
Cam
a)
Timing marks must be aligned.
b)
No visual tech on camshaft lobes lifter surface. Stock lifters only.
c)
If using a heavy-duty Connecting Rod, grinding between lobes of cam for
clearance only is permitted.
d)
Cam Profile limits:
INTAKE
EXHAUST
Lift (inches)
Degrees Lift (inches)
Degrees
.050 7E
BTDC to 0E
TDC .050 38E
BBDC to 33E
BBDC
.100 10E
ATDC to 17E
ATDC .100 21E
BBDC to 16E
BBDC
.150 29E
ATDC to 36E
ATDC .150 2E
BBDC to 3E
ABDC
.200 55E
ATDC to 64E
ATDC .200 21E
ABDC to 31E
ABDC
MAX MAX. Lift is
.233" MAX MAX. Lift is
.233"
.200 43E
BBDC to 33E
BBDC .200 76E
BTDC to 65E
BTDC
.150 13E
BBDC to 6E
BBDC .150 48E
BTDC to 40E
BTDC
.100 6E
ABDC to 13E
ABDC .100 28E
BTDC to 21E
BTDC
.050 23E
ABDC to 31E
ABDC .050 10E
BTDC to 4E
BTDC
EZSpin: Start -- 45E
to 60E
ABDC Lift -- .012" min. Duration -- 30E
min.
EXAMPLE: If EZSpin starts at 51E
ABDC, it must go to at least 81E
ABDC.
NOTE:
All Cam Profile and EZSpin Readings must be taken with zero valve lash, and
will be performed in accordance with the WKA Cam Profile Tech Procedure.
8) Flywheel
a)
Stock OEM 5 HP flywheel meeting WKA Tech Rules for the specific engine
model being used.
b)
Any flywheel key or no flywheel key allowed.
c)
Paintings and coatings other than minimum factory over spray are not
permitted. Machining is not permitted.
Chipped fins due to
poor casting are permitted. Broken fins are not allowed.
9) Fuel
Pumps
Stock OEM for the specific
engine model being used.
10) Head
a)
Stock head only.
b)
Copper head gasket minimum .020” allowed.
c)
Single flat planar milling of stock head allowed. No alterations to
valve cavity.
11)
Ignition
Any stock OEM
appearing electronic ignition allowed.
12)
Piston
a)
Stock OEM pistons for the specific engine model being used.
b)
Maximum .030" oversized piston allowed.
c)
Must retain stock rings, three (3), in stock positions.
13)
Connecting Rods
a)
Stock OEM rod for specific engine model used. Oil
hole may be enlarged
in OEM rod.
b)
Horstman Heavy-duty or ARC Heavy-duty H-Beam/I-Beam. Must be stock length
of 3.1283" + .0050”.
14Sealers
Gasket sealers,
thread sealers, and safety wiring on fasteners allowed.
15)Valves
a)
Rotocap or standard stock OEM valve assemblies for 130000 series engines
permitted.
b)
Must retain stock valve seat angle, diameter, and depth as per WKA Tech
Rules.
c)
Valve adjustments allowed.
d)
No overhead valves.
16)
Fuel
Methanol, Automotive
Pump Gas, Avgas, Sunoco Racing Fuel, or as specified by the track.
17)
Oil
Any oil or as
specified by track rules.
18)
Starters
a)
Stock OEM recoil starters mounted to engines allowed.
b)
External remote starters allowed. Must have WKA approved flywheel screen.
Unless specified herein, Sportsman Engines will adhere to the specifications
as found in Briggs & Stratton Service and Repair Instruction Manual.
The above rules state what you
are allowed to do to your Sportsman engine. Any violation of these
Specifications will be subject to penalties.
MODIFIED ENGINE SPECIFICATIONS
|
Engines Allowed
Briggs & Stratton 5
HP, 4-cycle, horizontal shaft only from the following list of blocks:
Raptor I, II & III,
130202, 130232, 132232, 133202, 133232, 13502, 135232, 135230, 133230, 555206,
555205 555168
Only one (1) engine
allowed in car during any race.
Engine Modifications
Engines must comply with WKA
STOCK 5 HP BRIGGS rules:
1) Engine
Breather System
Breather system must have solid
connection to oil catch can. Additional breather connections may be made to
crankcase and side cover if desired.
2) Balancing
Any engine balancing allowed.
3) Block
Porting and polishing allowed.
4) Cam
Any camshaft allowed.
5) Carburator
Any single carburetor. Single
manifold. No fuel injection, superchargers, turbochargers allowed.
6)
Crankshaft
Any crankshaft that retains stock
stroke of 2.4370" + .010". No strokers allowed.
7)
Exhaust
Any exhaust system allowed (must
pass state and track requirements). WKA RLV-91M muffler.
8) Flywheel
a)
Removal of the rim band on any Briggs flywheel is not permitted
b)
Briggs P/N 297949 is not allowed. This flywheel does not have a rimband and
exceeding 3200 RPM may result in catastrophic failure and serious injury.
c)
Flywheel shrouds must be installed at all times.
9) Head
Any head or head modification
allowed.
10)
Ignition
Any ignition allowed.
11)
Piston
Any make piston. 0.100” maximum
oversize.
12)
Connecting Rods
Any connecting rod allowed.
13)
Sealers
Gasket sealers, thread sealers,
and safety wiring on fasteners allowed.
14)
Valves
a)
Any valves allowed
b)
No
overhead valves permitted.
15)
Fuel
a)
Methanol only.
b)
Lubricating additives in fuel allowed, unless prohibited by track
regulations.
c)
Must
have specific gravity between .74 and .84 @ 60oF. Temperature correction will be
made for track conditions.
16) Oil
Any oil or oil additive allowed
except for flammable or oxidizing agents.
17) Starters
c)
Stock OEM recoil starters mounted to engines allowed.
d)
External remote starters allowed. Must have WKA approved flywheel screen.
The above rules state what you
are allowed to do to your Modified engine. Any violation of these
Specifications will be subject to penalties.
PURE STOCK ENGINE SPECIFICATIONS
|
Engines Allowed
Briggs & Stratton 5
HP, 4-cycle, horizontal shaft only from the following list of blocks:
Raptor I, II & III,
130202, 130232, 132232, 133202, 133232, 13502, 135232, 135230, 133230, 555206,
555205 555168
Only one (1) engine
allowed in car during any race.
Engine Modifications
Stock Brigg’s & Stratton
parts for the specific engine block being used only, unless stated otherwise. No
modification from stock except for the following:
1) Engine
Breather System
Briggs & Stratton stock breather
assembly modified to have a solid connection to vent hose. No modifications of
any kind to stock breather hole diameter.
Breather assembly may be replaced
with a flat plate with 1/8” fitting, which can be found at most Kart shops.
Breather hose must be connected only to the oil catch can.
2)
Block
a)
Governor system may be partially or fully removed.
b)
Governor paddle hole must be plugged.
3) Valves
a)
Valve adjustments allowed by grinding valve stem or lifters.
b)
Briggs & Stratton P/N 63709 valve guides allowed in intake and exhaust
positions.
4)
Pistons
a)
Briggs & Stratton stock pistons for the specific engine block being used.
b)
.030” maximum oversize allowed.
5)
Carburetor
a)
Brigg’s & Stratton P/N 397135, 299437, and 555129 only.
b)
Oil
breather, choke, and screw hole in carburetor may be plugged.
c)
Swirl may be removed.
d)
Any air cleaner installed in a safe manner. No filter may act an air ram.
Filter adapter may have rolled edge not to exceed Ľ” (.250”) from top. Adapters
may not be used without the filter element installed.
e)
Modified carburetor linkage and remote mixture adjusters allowed.
f)
Base-to-tank clamp holding the stock carburetor to the gas tank when a
mounting ear is broken off is permitted. All bolts must be tight.
g)
No additional holes are allowed to be drilled or tapped.
6) Exhaust
Any exhaust system allowed (must
pass state and track requirements). WKA RLV-91B muffler.
7)
Fuel
a)
Pump Gasoline (no additives).
b)
Must have specific gravity between .70 and .78 @60oF. Temperature
correction may be made for track conditions.
c)
Must
comply with any more restrictive requirements as may be defined by state or
track.
The above rules state what you
are allowed to do to your Pure Stock engine. Dimensions and requirements for
all engine parts will be taken from the current WKA rulebook as they apply to
stock engines. If necessary, comparison will be made to new Brigg’s parts for
appearance and finish. Pure Stock engines are subject to a claiming fee of
$350 cash for complete engine less clutch, exhaust system, and air filter. Any
violation of these specifications will be subject to penalties.
