"COWBOY'S"
Modified Farm Tractor Page!
QUESTION:....
What do you do with a yard full of
Junk Trucks and Parts Tractors?
ANSWER:....
You build a Modified Pulling Tractor!
What do you do with a yard full of
Junk Trucks and Parts Tractors?
ANSWER:....
You build a Modified Pulling Tractor!
New Class
We are trying to start a new class up here in Maine.
We are going to call it
"Modified Antique Farm" (ie. "Poor Mans Modified").
It's simple, somewhere between
"Stock Farm" and "Modified".
You start with a Stock Farm Tractor,
and add an Small Block Automotive engine.
It looks like a "Stock Tractor",
but performs like a Modified.
"The rules are posted below."
We are going to call it
"Modified Antique Farm" (ie. "Poor Mans Modified").
It's simple, somewhere between
"Stock Farm" and "Modified".
You start with a Stock Farm Tractor,
and add an Small Block Automotive engine.
It looks like a "Stock Tractor",
but performs like a Modified.
"The rules are posted below."
You start with a few Parts Tractors, and mix and match the best from both.
Then you find an Old Vehicle with a suitable engine to build-up.
Last of all,.. You marry the two together and what do you have?
Then you find an Old Vehicle with a suitable engine to build-up.
Last of all,.. You marry the two together and what do you have?
A Wheel Spinning, Noise Making,
Smoke & Dirt Throwing "BEAST"
That Brings The Crowd To Their Feet
Clapping And Cheering!
Smoke & Dirt Throwing "BEAST"
That Brings The Crowd To Their Feet
Clapping And Cheering!
But looks "Stock" from a distance!
The Sickness Returns!
Here's what I started with for a Tractor. In case you can't reconize it,
It's a Farmall "H"! Just enough parts to make a Modified Pulling Tractor!
It's a Farmall "H"! Just enough parts to make a Modified Pulling Tractor!
Our Proposed Engine!
This is what's left of a 1975 GMC 3/4 ton, with a 350 engine. This is going
to be our engine in our Modified tractor. It doesn't look like much right now,
but it will as time goes by! A Chevy small block is the cheapest to build
as the parts are so redially available.
to be our engine in our Modified tractor. It doesn't look like much right now,
but it will as time goes by! A Chevy small block is the cheapest to build
as the parts are so redially available.
Here's Engine Parts!
We are not getting too wild when building this engine. A man can go broke real fast
trying to keep up with all the new and improved preformance products on the market.
Aftermarket parts are available through many catalog sales warehouses.
Just check the advertisements in the back of a Hot Rod magazine.
trying to keep up with all the new and improved preformance products on the market.
Aftermarket parts are available through many catalog sales warehouses.
Just check the advertisements in the back of a Hot Rod magazine.
Rebuilding The Transmission!
This is a Turbo Hydro-Matic 350 (TH350) from a mid 70's automobile.
Most GM automobiles were fitted with this TH350, but some had the larger TH400.
The TH400 is bigger and stronger and will take more torque than TH350!
The TH350 outnumbers the TH400 three to one. The TH400 is also a bit longer.
For our application, with a moderately built engine, the TH350 will work fine.
Both transmissions came with long or short tail shafts, as required per application.
We are rebuilding the transmission ourselves with a premium rebuild racing kit.
Don't be skimpy on the transmission when rebuilding it! Use Good Parts!
Most GM automobiles were fitted with this TH350, but some had the larger TH400.
The TH400 is bigger and stronger and will take more torque than TH350!
The TH350 outnumbers the TH400 three to one. The TH400 is also a bit longer.
For our application, with a moderately built engine, the TH350 will work fine.
Both transmissions came with long or short tail shafts, as required per application.
We are rebuilding the transmission ourselves with a premium rebuild racing kit.
Don't be skimpy on the transmission when rebuilding it! Use Good Parts!
Engine Specifications!
Block:...350 chevy V-8 bored .030 over
Crankshaft:...Cast crank from 400 Chevy,
Main bearings turned to std for 350 block, Rods .010 undersize.
Rod Length:...5.7 inch from 350 Chevy
Pistons:...TRW Flat top for 383 conversion
Timing Chain:...Double Roller Type
Cam:...Wolverine Hydrolic Cam (Custom Ground)
Intake Manifold:...Weiand X-CELerator single plane alumiumn high rise
Heads:...Stock Cast Iron 1.94/1.50 valves, 76 cc combustion chambers
and 170 cc intake runners
Valve Train:...Stock GM valve train and valve covers
Water Pump:...Stock GM cast iron, modified for more flow and pressure
Carburetor:...Holley 600 w/vac secondaries
Transmission:...GM Turbo Hydro-Matic 350 (TH350) with a shift kit installed
Torque Converter:...B&M Hole Shot 2400
Crankshaft:...Cast crank from 400 Chevy,
Main bearings turned to std for 350 block, Rods .010 undersize.
Rod Length:...5.7 inch from 350 Chevy
Pistons:...TRW Flat top for 383 conversion
Timing Chain:...Double Roller Type
Cam:...Wolverine Hydrolic Cam (Custom Ground)
Intake Manifold:...Weiand X-CELerator single plane alumiumn high rise
Heads:...Stock Cast Iron 1.94/1.50 valves, 76 cc combustion chambers
and 170 cc intake runners
Valve Train:...Stock GM valve train and valve covers
Water Pump:...Stock GM cast iron, modified for more flow and pressure
Carburetor:...Holley 600 w/vac secondaries
Transmission:...GM Turbo Hydro-Matic 350 (TH350) with a shift kit installed
Torque Converter:...B&M Hole Shot 2400
New Engine Size:
383 CID
Keep Checking Back!
I Will Add More As I Go!
I Will Add More As I Go!
ANTIQUE FARM-MODIFIED PULLING RULES
"Preliminary Rules-Subject to change"
(Poor Mans Modified Tractor)
#4000 and #5000 classes
"Preliminary Rules-Subject to change"
(Poor Mans Modified Tractor)
#4000 and #5000 classes
#1.....Engine Specifications:
A...Engine must be tractor engine or replaced with OEM automotive V-8 small block, V-6, Straight 6. (NO aluminum blocks unless OEM stock,.. Aluminum aftermarket heads allowed,... limit of two valves per cylinder and one spark plug per cylinder)
B...Limit of one engine. (No Turbine Engines)
C...Must be normally aspirated, (NO Turbos) One 4 barrel or two 2 barrel carburetors (MAX of 4 venturis), any CFM. (NO Six Packs)
D...Use of throttle body injection is allowed. (No milti-port injection except for diesel engines)
E...Normally aspirated diesel engine w/o a turbo is allowed.
F...Engines may be gasoline, diesel, or propane types. (NO Alcohol, Methanol, or Oxygen Carriers allowed,..."example: Nitrous Oxide")
G...No "Ethier" (Starting Fluid) cans allowed on tractor while pulling.
H...Foot throttles are permitted providing they have a toe strap.
I...All tractors must have a "Deadman" throttle. Working in a forward-Rearward direction. Rearward being closed.
J...All throttles must have 3 return springs, one on the lever or foot pedal, and two on the carburator linkage arm, hooked independantly. If tractor has both lever and foot throttles, each will require return springs.
K...Exhaust must exit vertically. (NO down or side exit exhaust) Headers are allowed.
L...Only "Flat Head" pistons allowed on Automotive type engines. (Will be checked through spark plug hole)
M...All other engine modifications are allowed. (ie: Cams, Manifold, Ignition, Etc)
N...A 3/16 inch steel Block-Saver plate is required between engine and transmission/clutch housing on those using an Automotive type engine.
#2.....Transmission:
A...Engine transmissions are allowed, being either standard, automatic, or torque amplifier type.
B...If standard, a steel bell housing is required (NHRA approved), (A factory cast bell housing is not a steel bell housing) or a transmission scatter blanket (NHRA approved) will be installed around the bell housing in order to pull.
C...If automatic, a transmission scatter blanket (NHRA approved) is required to be installed around the transmission.
D...Automatic transmissions are required to have a positive reverse lockout so transmission can not be accidentally shifted into reverse.
E...If a T/A (Torque Amplifier) is factory in the tractor transmission, no other safety items need be installed.
F...Tractor Transmission must be intact and have all speeds in working order (No doubling up of one gear) Tractor Transmission will be checked for compliance.
#3.....Safety Shields:
A...A safety shield is required to be installed along both sides of the engine as follows. Must be a minimum of 1/8 steel, to extend 2 inches below the crankshaft throw and to the top of the piston travel, at least as long as the engine block. Motor mounts, starter, and accessories do not count as a shield. Shield must not be attached to the engine.
B...A shield must cover 1/2 inch either side of the horizontal travel portion of a engine driven cooling fan, 360 degrees, be at least 1/16 inch steel. Shield may be attached to engine.
C...A electric cooling fan does not need a shield.
#4.....Frame:
A...Must start with a antique production farm tractor (Before 1973), and retain tractor transmission and production front end.
B...Production front end, either wide or narrow is allowed. (NOT to be modified or custom made)
C...Weight may not extend rearward beyond rear wheels.
D...Front weights may not extend more than 24 inches beyond the front of the tractor frame. (Front tires or front end assy. are not considered as part of the frame)
E...All weight must be firmly attached to tractor. (Bungee cords or rubber straps NOT allowed)
F...Any weight lost while under the green flag is grounds for disqualification. Loss of weight after being flagged "Red" does not count as disqualification.
#5.....Tractor Length/Apperance:
A...Finished tractor must not be extended longer than 18 inches over stock.
B...Frame and/or frame rails may be extended.
C...Tractor must have a original apperance.
D...Tractor must have original looking hood.
E...Tractor must have original nose assembly.
#6.....Tires:
A...Max tire size is 18.4 x 38.
B...Max width of rear or front axle is 9 feet and tires must track within that area.
C...No duel wheels allowed.
D...No tire chains allowed.
E...No tire studs allowed.
F...Fenders are required. Fenders must extend above tires height. Custom made fenders are allowed.
G...No 4x4 tractors allowed.
H...Cut tires are allowed.
#7.....Hitch and Wheelie Bars:
A...Hitch must be same as for "Stock" tractor division. Top of hitch will be no higher than 20 inches from ground. Hitch will be no shorter than 18 inches from center or rear axle to rear hitching point. (Hole for chain) There will be a 3 inch hole in a piece of steel, not thicker than 1 inch with no less than 7/8 inch of cross-sectional material, nor more than 1-1/2 inch from back edge of hitch.
B...Wheelie bars are mandatory for all tractors.
C...Bars must extend rearward beyond rear tires so skid plate is completely behind tires. Be a minimum of 2 1/2 inch square tubing, 1/4 inch thick.
D...Skid plate must be no smaller than 5 inches x 5 inches square being at least 1/4 inch steel. Plates may not be any higher than 10 inches from the ground.
E...Wheelie bars may not be attached to hitch in any way.
F...Wheelie bars must support weight of tractor and will be checked by Tech.
#8.....Electrical:
A...A break away switch (Kill Switch) is required, to be within 6 inches of centerline of tractor, and and no more than 18 inches above hitch height on the rear of tractor. Must be mounted to chassis and not mounted to the hitch or seat.
B...A battery disconnect switch is required, to be easily accessable by driver while operating the tractor.
C...A seat with a back is required.
D...No tip seats allowed.
#9.....Safety:
A...Helmets are required to be worn while pulling tractor is hooked to sled.
B...A rear facing reverse safety signal light is required to assure safety for the sled operator.
C...Fire extinguisher (Class ABC 2-1/2 lbs) is mandatory to be within reach of driver while operating tractor.
D...No alcohol or drug consumption will be tollerated. Anyone found under the influence will have themselves, pit crew, and tractor disqualified.
#10.....Class Rules:
A...Same safety rules apply as for pulling as "Stock" tractors. (Except as stated below) "MSPA" Rules Apply.
"CLICK HERE TO GO TO STOCK FARM TRACTOR PULLING RULES PAGE!"
B...Classed will be #4000 and #5000 classes.
C...No RPM limits.
D...No speed limits.
E...No power take off (PTO) is required.
Click Here To Return To
COWBOY'S Antique Tractor
Home Page!
COWBOY'S Antique Tractor
Home Page!
This page was installed on January 8,1999
Last updated on Tuesday, September 28,1999
It was constructed and is maintained by
"COWBOY"
If I can do it, anyone can!