We talk about reliability with our turbo systems and recommend the turbo system be put on a stock engine.  Do not modify the carburetor or install a larger carburetor.  The stock carburetors have proven themselves able to perform extremly well with the turbocharger kit with no modifications necessary.  A stock engine has been engineered and built to work at full horsepower all day in all kinds of weather conditions. It has stood the test of time with many engines lasting in excess of 25 years.

The turbo system at 10 lbs of boost will stress the engine approximately 8% at maximum boost pressure. The engineering manual states that approximately 18-21% if the intake charge is burned at TDC (top dead center). This is the same whether the engine is turbocharged or not. The big power comes as the fuel air mixture continues to burn and build high pressure as the crank arm approaches 90 degrees. With a large combustion chamber and the low compression ratio many customers report that the torque and horsepower of the stock engine has more than doubled at stock RPM.

Our turbocharger kits have been sold for about five years. Our first customers are still farming, pulling, and going on tractor trips and report no problems at all.

In the quest for more power others have purchased high compression pistons, larger modified carburetors, new stroked crankshafts and connection rods. They have spent many hours and an awful lot of money for machine work to gain additional power from an antique tractor engine.

One fellow stated that he spent in excess of $14,000.00 to bore and stroke a super M engine to more than 400 cubic inches. He stated he got 90 horsepower at 2100 RPM from this engine. He had another tractor, a stock Super M, that he purchased a turbocharger kit for and reported over 100 horsepower at 1800 RPM from this stock engine. The turbo charger kit was installed in one afternoon at a small fraction of the cost and labor.

Simple math calculations will tell the story:

264 Cubic inch X 1800 RPM = 475200

475200 X .50 = 237600 (half the time it runs as an air compressor)

237600 X .55 (volumetric efficiency) =130680

130680 divided by 1728= 75.625 cubic foot of air

75.625 X .069 = 5.218 weight pounds of air.

5.218 X 10 = 52.181 horsepower (10 horsepower per 1 weight pound of air)

Do the above calculations and see if you don’t arrive at about the advertised horsepower of a stock four cylinder tractor engine. Note that the volumetric efficiency is just 55% for a four cylinder tractor engine. No matter how big you make it, it is still 55%.

We are using 55% for the above example, however the turbocharger kit will substantially raise the volumetric efficiency to over 80%. 

Take the above number of 52.181 horsepower and turbo charge it to 10 pounds boost. 52.181 X 1.7 = 88.708 horsepower. Try it again at 12 lbs, 52.181 X 1.8 = 93.9258 horsepower. Remember that these calculations are with 55% volumetric efficency. Try these calculations with 60%-70% and 80% volumetric efficiency. Air temperature and other factors play a part. For example our long intake tube from the carburetor to turbocharger will run cold causing the engine to receive a very dense fuel/air mixture resulting in more power and efficiency at all engine speeds from idle to full power.  

Remember the fellow that spent in excess of $14,000 to get 90 horsepower from 400 C.I? Do the math and see what happens.

Turbochargers have been around for many years on tractors, trucks, and cars. Change the oil once in a while and it will last until you sell the tractor. The turbocharger kit can be taken off and sold separately to recover your investment. Many years of fun and then recover your expenses, try that with a bored and stroked engine.

As often happens a tractor puller gets sucked in by super trick parts that look good and are sold with a technical pitch that is hard to resist. He or she is sold specialized parts that won’t fit anything else. Modified parts that don’t work as good as the stock parts they replace.

The engineers designed the parts, pistons, carburetors etc, to work under all kinds of conditions. I believe that these stock parts are about 90% as good as you can get. I think a smart person can maybe be able to work on the part to get it to 95-100%.

However many of these modifications end up going the other way. There may be 5-10% to be gained, however there is 90% to loose. I recommend that a tractor puller stay away from these odd ball parts and stick to conventional parts that have stood the test of time. It will be cheaper in the long run to use conventional parts and concentrate on fine tuning the stock parts.