In his Usenet article, Berg continues:

In the Holtz paper I cited from 1960, there are two extremely relevant sections which your challenge has prodded me to notice. I urge you to read them also. The first section is: 'Engine tests' on pages 68 and 69.

Let's turn to that other reference that has given Mr. Berg a bit of confusion, the paper by Holtz and Elliot in the 1941 Transactions of the American Society of Mechanical Engineers, Vol. 63, Feb. 1941, pp. 97-105. On page 98, we find exactly the same graph referred to in Berg's note 22. But on page 99, we find some very interesting numbers - some of the raw data used to generate the graph.

Engines A and B in the paper are four-cylinder four-stroke engines. Engine B is rated at a maximum 70 brake horsepower; it has a displacement of 226 cubic inches and maximum RPM of 2600.

Remember these crucial words from Berg's paper: "At full load, which corresponds to a fuel/air ratio of 0.055, the oxygen concentration in the exhaust of any Diesel is 4%." It has already been noted he is on very shaky ground in claiming this was true for "any" diesel, when it's clear that this graph was generated from these two specific engines. But is he right about the rest?

Experiment B-12 ran the engine at 1400 RPM at a fuel/air ratio of 0.056 (one thousandth more than Berg's 0.055, but one hopes he won't argue that the extra thousandth makes a difference). Oxygen was 3.44%. The difference between 3.44 and 4 doesn't look like much, but in percentage terms, it's a difference of 14%.

Is he right about full load? Well, it depends on what he means by "full load." If he is talking about maximum rated torque at the given RPM, yes. But if he's talking about full power output, no. Experiment B-12 was run with a net output of 37.8 HP.

Is he right about "any diesel?" Turn to the discusson by H. E. Degler, University of Texas professor of mechanical engineering, on p. 104:

Engine manufacturers and operators have been increasing jacket-water temperatures in recent years, some as high as 212 F at atmospheric pressure, thus taking advantage of the latent-heat cooling effect in addition to the sensible-heat removal. These higher temperatures will reduce the "chilling effect of direct oxidation reactions," as mentioned by the authors, and assure lower CO, decrease aldehydes, and reduce the free carbon in the engine exhaust.

So it seems there are some other considerations which affect exhaust gas composition. Without more information on exactly what kind of engine was used, there's no way of knowing if Soviet diesels used those higher water temperatures. Yet from two engines Berg thinks he knows what's true for "any diesel."

Let's look at some text of the Holtz-Elliot paper on p. 99:

Although Fig. 2 [the same graph Berg uses as Fig. 6 of his own paper] presents data on exhaust-gas composition at fuel-air ratios on the rich side, such conditions of operation are not normal and were obtained in these tests by changing the adjustment of the stop limiting the travel of the rack on the fuel pump of engine B. After this change the fuel injected at full throttle was increased by approximately 60 per cent.

Now, these are out of normal range. But the technique used was not overloading. It was adjustment of the fuel system. And they said nothing about restricting the air intake as was done in experiments performed by Pattle et al. One must wonder what would happen if they tried doing both?

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