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©2010 by Zack Peterson and Podium Finish, LLC – www.antiquetractorpullguide.com

Welcome to the Podium Club!

As a member of the Podium Club, you have made a very smart decision to access extremely exclusive information related to Tractor Pulling. The information found at antiquetractorpullguide.com is like no other information out there. The tips, tricks and secrets of successful tractor pulling are designed to improve your performance at the next tractor pull, while having more fun at the same time.

Podium Newsletter

On all of the Ground Speed Charts that are posted in the member area of antiquetractorpullguide.com, there is a table that shows different tire sizes and a corresponding Static Load Radius associated with each. Static Load Radius is the distance from the center of the axle to the ground with the weight of the tractor on the tire. This takes into account the squash of the tire due to a load when properly inflated. Why is this distance used for ground speed calculations? Because it is the most accurate way to calculate ground speed.

Why is circumference not as accurate?

Circumference is the distance around the edge of a circle. To use circumference is to assume the tire is perfectly round. In other words “rolling circumference” is an approximated perfect circle. The radius using a perfectly round tire is longer than the Static Load Radius. See the diagrams below that show this graphically.

Why don’t you use the Rolling

Circumference of tires for ground speed calculations, and what exactly is “Static

Load Radius” anyway?

February 2010

RadiusStatic Load Radius

Tire bearing the weight of a tractor


In most cases, the difference between Static Load Radius and the radius of a Rolling Circumference is less than an inch or so, but it is enough to significantly affect ground speed calculations, especially as gears get faster.

With respect to the gearing and ground speed charts found at www.antiquetractorpullguide.com, every measure was taken to make the values as accurate as possible.

Massey Harris Mustang – The Engine Recipe

With the Mustang’s F140 Continental completely disassembled, it is time to consider what modifications to make to ensure enough power is available on the track. In using tips found in The Antique Tractor Pull Guide, there are three major modifications that will be done to this engine. The following three tips are always a good idea for any engine built for pulling.

Bore increase: The Continental F140 engine shares a common block with the larger F162 engine. The only major difference between the two engines is the bore size as they share the same stroke. Therefore, the F140 can simply be overbored to accommodate the larger F162 piston.Bonus tip: Why stop there? The very first secret of The Seven Secrets is“Have Enough Power”. When building an engine for pulling, always build it to the limits of the modifications you intend to do since it never hurts to have more than enough power available. In this case, since the F140 block will accommodate F162 pistons, why not bore it larger for the F162 rebore kit? By installing +.060” F162 pistons, the engine now becomes 168 cubic inches, and as it’s commonly said, “There is no replacement for displacement”. These pistons were available off the shelf for $34.50/pc from Montes Equipment in Chicago, IL. Sometimes it’s nice to use common engine parts.

Old piston vs. new piston – new piston is 0.31” bigger in diameter


Camshaft: The camshaft will be reground for high torque. A cam grinding service will usually increase the lift and duration of the cam, which controls how far and how long the valves are open inside the engine. This in turn increases power. Camshafts can be ground for peak performance in different rpm ranges. For the Mustang, the engine was rated at 1500rpm on the drawbar and 1800rpm on the belt. The camshaft will be reground for peak performance in the 1500-1800rpm range since local rules allow 10% over stock rated rpm. Even if the engine is allowed to run over 1800rpm, there will be a “power bulge” as the engine lugs down.

Massey Harris Mustang – The Engine Recipe (cont)

Cam lobes control valve timing

Reground cam lobe with added lift and slightly different shape, which controls duration


Massey Harris Mustang – The Engine Recipe (cont)

High Compression Cylinder Head: This is where it pays to do a little research. There were many different cylinder heads that were made for the Continental L-head engines. This practice is fairly common for a lot of old tractors – cylinder heads can be swapped to increase compression ratio. Agood place to start looking is at propane or LP type engines. For this engine, a later head off a similar engine was found that is a little over 8:1 compression ratio. With the increased bore size, final compression ratio will be around 9.8:1, which is about perfect for a pulling engine.

New Cylinder Head

Existing Cylinder Head

New cylinder head combustion chamber –more shallow (note spark plug thread depth)

Existing head combustion chamber


Learning the Hard Way – Crawler story #1

Each newsletter I will share a story from my past where I learned a valuable lesson, usually by damaging something, hurting myself, or embarrassing myself.

In 2003, my father bought a Minneapolis Moline Motrac crawler at the Red Gaede auction in Limon, CO. Most folks might not know that Minneapolis Moline did in fact build a crawler tractor. This particular crawler was built in 1960, has a 206 cubic inch diesel engine, similar to the 445 and 4 star wheel tractors and is one of only 161 ever built. The crawler was trucked out to Oregon not long after the auction and when it arrived we had the task of figuring out how to unload it. The factors were not stacked in our favor:

� No loading dock

� Crawler didn’t run and has a bucket loader on it

� Hauled in on a semi with a step deck trailer

� We didn’t own any decent or large loader tractors to assist

Since we hadn’t had too many tractors trucked in, we really hadn’t thought about a building loading dock just yet. The crawler was delivered by a semi with a step deck trailer and luckily the rear end of the trailer was similar in height to our gooseneck trailer. This made it relatively easy to get the crawler off the semi. Using a Minneapolis Moline UB Special tractor, we were able to pull the crawler onto the deck of our trailer – step one, a success. Since the gooseneck has beavertail and pull out ramps (all steel), there was a path for the crawler to make it to the ground. All we had to do was tow it off the trailer, right? This is the part where we learn.

The crawler was pointing backwards on the trailer, which meant the bucket was in the way if it were to roll down the ramps. Thinking we were so smart, we rigged up a chain to go under the bucket so that when it was tensioned, the bucket lifted. I was tasked with “steering” the crawler down the ramps as my father tensioned the chain with the UB Special. The bucket went up and the crawler began to move, so far, so good. Then the crawler nosed over onto the beavertail section of the trailer where the deck is all metal. Metal deck meets metal track pads and the sliding began. The crawler suddenly turned sideways in the beavertail and slid further off down the ramps. Fearing the worst, I bailed off, hitting the ground at a full sprint in fear of being crushed by a crawler rolling off the trailer.


An awesome delivery – the MM Motrac and a MM U High Crop

Street pads meet metal ramps – the aftermath. OOPS!

The easy part – crawler transferred to gooseneck trailer

The crawler’s left track actually slide into the ground first and the whole machine tipped up as if it wanted to roll over. It came back down, slamming against the trailer with a loud crash and then a silence followed. I exclaimed, “Well, that’s one way to do it!” as we all stood there in disbelief.


Did that really just happen?

Putting a little stress on the trailer

Hitch up the UB Special and let’s get

this thing moved


There is a video clip of the event that will be posted at www.antiquetractorpullguide.com

Motrac back on terra firma – whew!

Tractor Tip Follow Up – Simple Tachometer Installation

In order to install a digital tachometer on a gasoline pulling tractor, the very first thing to address is the spark plug wires. The way most electric tachometers are designed, they use a signal wire pick up from the coil. Any electromagnetic interference with this signal wire will cause the gauge to read erratically or not at all. With solid core spark plug wires that are not electromagnetically shielded, they emit so much interference that a digital tachometer will not work. Using shielded spark plug wires such as MSD helical core wires, with avoid any problems completely.

Digital tachometers wire up very easily. The tachometer featured in Tractor Tip 106 is called a Glowshift tachometer. This little tachometer works very well for reading engine rpm and only uses a 3 wire connection. The wires are:

Red – Battery power

Black – Ground

Green – Signal wire (attached to coil wire that goes to the distributor)


Notice high performance MSD shielded spark plug wires, and signal wire going to the coil (green).

For more information on this style of tachometer, visit www.glowshiftdirect.com.

Tractor Tip Follow Up – Simple Tachometer Installation

(cont)

Tachometer mounted on the battery box, visible from the driver’s seat.


Podium Newsletter

Coming next month…

� Geared down: Cockshutt 30 vs. the power track

� Countdown to the first pull of the year

� Massey Harris Mustang progress

� Tractor Tip Follow Up

� And more…

I want to hear from you! If you have feedback, requests or information you would like featured, please send an email to: [email protected].

Cockshutt 30 pulling at Banks, OR in August, 2006.

podium newsletter 3 - feb10antiquetractorpullguide.com/wp-content/...3-feb10.pdf · microsoft...

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