Vermont Tractor Pullers Association
Sport Stock
1050 lbs & 1150 lbs
2015-2018
Driver Eligibility:
1.
General Rules apply.
2.
Youth ages 14 and older may pull sport stock classes with
written parental consent. EXCEPTION: Any youth 12-14
wishing to compete in sport stock class must submit an
application to committee for approval by Dec. 31. To submit
an application, the youth must have at least 1 year prior
pulling experience.
3.
Helmet, full length pants and closed toe shoes REQUIRED.
4.
A tractor may be entered only once per class.
5.
A sport stock tractor competing in the sport stock class
cannot move up a class in the same event.
Chassis:
6.
Transaxle housing and chassis must be OEM available in a
commercially produced garden tractor.
7.
No aftermarket multi-range gear box.
8.
Engine must be OEM available for lawn and garden. No
automotive, motorcycle, ATV, marine, snowmobile, etc, type
engines allowed.
9.
Tractor must have stock appearing hood and grill (nose
piece). Switching to another factory sheet metal is
permissible.
10.
Maximum wheel base is 52 inches.
11.
Maximum distance from center of rear axle to farthest point
forward is 96 inches.
12.
No additional power source attached to drive line.
13.
Flywheel and clutch must be shielded with stock shields or
1/8 inch steel or 3/16 inch aluminum 360 degrees.
14.
Single cylinder tractors not running stock side panels need
to be shielded with 1/8 inch steel or 3/16 inch aluminum
plate opposite cam side height and width of block. This plate
would need to be mounted with two bolts to the frame and at
least one bolt to the head.
15.
Wheelie bars must be rigid in all directions and able to
support the tractor and driver in the heaviest class. Each
skid shoe must be a minimum of 1.5”x 2” or the use of 5”
round wheels 1” wide is allowed. Tractor must have 2 skid
shoes or 2 wheels. The wheelie bars must be a minimum of
5” from the rear most part of the tire and maximum of 10”.
The bars must be a maximum of 5” from ground to bottom of
skid shoes or wheels. A vertical bumper bar 6” in height in
rear most position is required. Weights on back of tractor
must be contained up to 1” before end of the wheelie bars.
(Refer to diagram in back of book)
16.
Maximum hitch height is 13”. Must provide own clevis or
straight flat plate with 1 ½” hole with a dead man zone of 3”
on each side of the hitch. Hitch must be rigid in all
directions. The kill switch must be centered approximately
10”-12” above the hitch in this area. (Refer to diagram in
back of book)
17.
ALL TRACTORS MUST HAVE a minimum of 1 lb fully
charged fire extinguisher on board in reach of operator. A
functional gauge on the fire extinguisher is REQUIRED.
18.
ALL TRACTORS MUST HAVE rear fenders extending a
minimum of 4 inches out over the tires. OEM fenders are
acceptable. It is recommended that foot well and rear fender
be attached to avoid the possibility of operator’s foot being
pulled through to come in contact with tire.
19.
ALL TRACTORS MUST HAVE at least a 3 inch seat back.
Engines:
20.
a. One or two cylinder, flat head or overhead valve,
naturally aspirated, carbureted, cast block, four cycle
gasoline engines.
b. Naturally aspirated Diesel engines up to 42 cubic inch and
up to 3- cylinder allowed.
21.
Engine blocks must remain stock appearing on the
exterior.
22.
Stock intake manifolds must be used on all engines.
23.
In all engines the following engine components must
remain in original position:
a.
Crankshaft
b.
Camshaft
c.
Valves
d.
Rocker arms.
24.
Stock valve diameter must be maintained for all engines.
25. Stock crankshaft stroke must be maintained for all v-
twin engines.
26.
Engine RPM’s must be controlled by mechanical governor.
Maximum limit: 4500 RPM for Gasoline engines and 4000
RPM for Diesel engines.
27.
ALL TRACTORS MUST HAVE a functional breakaway kill
switch to cut ignition and fuel pump. Diesel engines MUST
HAVE air shut off to cut the engine, as well as electronic fuel
pump disconnect .(Refer to diagram in back of book)
28.
All Tractors must have a “dead man” throttle. Throttle must
return to the idle or closed position when the pedal or lever
is released.
29.
Exhaust must discharge within 10 degrees of vertical.
Gasoline Powered Tractors:
30.
Overhead Valve engines have a maximum of 38.8 cubic
inches. No aftermarket cylinder heads for overhead valve
engines.
31. Flat head engines have a maximum total engine
displacement of 45 cubic inch. Billet aluminum heads
are allowed for flat heads.
32.
Carburetor airflow must be controlled by a throttle shaft
actuated butterfly. Carburetor must be stock appearing,
lawn/garden type.
33.
Intake tract must pass thru a maximum 1.2 inch diameter
round restricted area or equivalent.
Explanation:
a.
One barrel carburetors may be a maximum 1.2 inch
diameter.
OR
b.
Two barrel carburetors may be a maximum .866 inch
diameter per barrel
AND
c.
No air may enter intake tract downstream of the 1.2 inch
(or equivalent) restriction.
34.
No electronic rev limiters
35.
Gasoline only.
Diesel Powered Tractors:
36.
Engine blocks must be clearly marked with the engine
model number. Valve cover tag with engine displacement
must be in place for engine identification.
37.
Diesel fuel only
38.
No other injection will be allowed. (water, propane,
alcohol, etc.)
39.
Stock manifolds only.
40.
No ice boxes or intercoolers.
Tires and Wheels:
41.
Maximum tire size: 26 x 12.00 x 12