EnviroMax Plus is yet another "fuel-saving" additive to recently begin selling though multi-level marketing. This immediately triggers warning bells among sceptics - although some perfectly good and effective products are sold through MLM, it is also a common method employed by scammers and snake-oil salesmen to maximise revenue from ineffective products. (Commonly, the "early adopters" make much, if not most, of their money by recruiting lower-level sales people rather than directly through product sales.) An additional effect is that there may be thousands of lower-level distributors, all with a financial stake in the product, who will pop up on discussion forums and blogs to praise EnviroMax Plus and offer glowing "independent" reviews and testimonials.

Theory

EnviroMax claims to have a catalytic effect on fuel, making it burn more completely. The immediate problem is that the idea that normal engines burn only 85% of the fuel (leaving 15% to escape wastefully from the exhaust) is just wrong - in reality, a modern engine in good condition burns something like 98% of the fuel, leaving very little room for improvement. So whatever the way in which it supposedly improves the burn, it's hard to see how the savings can be as large as is claimed (up to 35%).

There is also a claim of a cleaning effect - I am equally sceptical that that is of great benefit.

Test results - EPA Testing in Georgia

This document shows details of some measurements made as part of an Inspection & Maintenance test ("smog check") on a vehicle, before and after using EnviroMax Plus. Some impressive-looking emissions reductions are quoted, with the comment that this "conclusively was a direct result of" the addition of EnviroMax Plus.

As a scientist, this statement immediately sets off all kinds of alarm bells for me. How do we know it is "conclusively" a result of EnviroMax? Where are the repeat tests of the "baseline" vehicle, to establish the test-to-test variability? Where are the repeat tests after the product was added? Where is the "A-B-A" test, where you stop using the product and check that the emissions go up again? There are many ways to scientifically evaluate "gas-saving" products, but this is not one of them!

The mileage (fuel economy) improvement mentioned is apparently not measured on the test station's rolling road, but is simply the driver's record of economy measured in normal driving. In other words, it's just an uncontrolled testimonial, with all the problems (varying driving style, journey type, traffic, weather, etc) discussed here.

Overall, this test absolutely does not represent scientific fuel economy testing; in particular it falls well short of the EPA's standard for evaluating gas "saving" additives. Indeed, the EPA specifically exclude Smog Check-type evidence from their evaluations, precisely because of the inherent errors and uncertainties.

Test results - Texas Tech University

This study describes work done by the Chemical Engineering department of Texas Tech University. Clearly plenty of thought has gone into this work, but where it falls down - as is very common with such studies - is that there is no scientific measurement of fuel economy. Instead the study relies on uncontrolled on-road measurements, which are (as described above) susceptible to very large errors.

There is also the concern that the test data relates exclusively to diesel combustion, and cannot necessarily be read across to gasoline (which is what most customers are likely to be using).

Endorsement by Johnny Rutherford

While Johnny Rutherford is clearly a very skilled and successful racing driver, that does not automatically make him an expert on gasoline engine combustion. See the comments in my biography about this.

The comments from Larry Mankin again do not seem to represent any kind of scientific evidence, particularly when it comes to fuel consumption.

Registration with the EPA

EnviroMax Plus is registered with the EPA, and Extreme Research promote this as if it were an endorsement by the EPA of their claims. In fact, registration just involves "providing a chemical description of the product and certain technical, marketing and health-effects information" - there's no need for Extreme Research to provide proof of claims of improved economy and emissions in order to achieve registration.

Testimonials

As with most fuel "saving" products, the primary evidence in favour is uncontrolled on-road testing, where people compare their economy with and without EnviroMax Plus. As explained here, it is very easy to get false results from this sort of testing since fuel economy is very strongly affected by traffic, driving style, weather, etc. Especially significant is the "placebo effect" - anyone who has invested in EnviroMax Plus, and wants to see it work, will naturally (if unconsciously) adopt a more economical driving style. (Also, do not forget the "MLM effect" mentioned at the top of the page.) Similarly, claims of improved performance are almost entirely restricted to comments along the lines of "my car feels quicker now", which could very easily just be wishful thinking.

There is a long history with fuel "saving" products of glowing testimonial evidence followed by scientific testing proving that the product/device has only a tiny effect (for example, the Ecotek CB-26B. Because of this, governments and other regulatory bodies generally say that testimonial evidence on its own is not sufficient to demonstrate the effectiveness of any fuel "saving" product. (See for example the advice from the Federal Trade Commission.)

Those who market and support EnviroMax Plus, as with other fuel "saving" products, always condemn those who criticise them without trying for themselves. "If you haven't tried it in your car, you can't comment on it", they say. But the point is this: the sceptics know very well that any testing they could do would prove absolutely nothing, due to the natural fluctuations in fuel consumption. Maybe they would see an improvement, maybe they wouldn't. Either way it would not demonstrate conclusively whether the product works or not. Only rigorous scientific testing can do this (and such testing costs far more than any independent individual such as myself can afford).

Emissions reduction and economy gain

Some commentators have noticed reductions in exhaust emissions when using EnviroMax Plus, and regard this as proof of economy improvement. There are two problems with this:

First, emissions measurements have their own natural variability. Factors such as engine temperature, atmospheric conditions, and (crucially) catalyst temperature can all strongly influence emissions levels. Simply driving the car hard for a few miles can heat the catalyst enough to give a large drop in emissions as the catalyst is then working better.

The second, and more important, problem is that emissions measurements are a poor guide to economy. It is true that very high levels of emissions (especially unburnt fuel) - caused by a faulty spark plug, for example - do imply bad economy. But on modern cars in good condition the level of unburnt fuel in the exhaust is already so low that further reductions are essentially insignificant in terms of economy. Partly for this reason, the US Environmental Protection Agency's guide to evaluating fuel "saving" devices specifically excludes emissions data such as the Inspection & Maintenance (I/M) test as evidence of effectiveness.

Conclusion

• Claims to greatly enhance fuel burning through a catalytic process seem implausible

• Opportunities to save significant amounts of fuel through reduced unburnt fuel fraction are in any case very limited

• The test data is mostly uncontrolled testimonials

As with all aftermarket fuel "saving" devices, my advice to Extreme Research is simple: if you believe in your product, spend 0.01% of your income on rigorous scientific testing to prove it really works. If you don't, sceptics will draw their own conclusions as to why not.

Please also read the general comments on fuel "saving" devices, if you have not done so already.

If you found this page helpful, you may like to support my work. If you think I have made a mistake, or am talking complete nonsense, please take a moment to read the Response to Critics before saying so in public (on discussion Forums and the like).