Perhaps my use of Opti products is 'overkill', but I like to stick with what I know works. In the commercial lawn business, I agree that use of certain expensive products is not justified, but for the homeowner who changes oil once a year, the cost is not important. FWIW, I also use Opti-2, but at 66:1. It probably is okay at 100:1 but my nerve runs out at 66:1. It has been working for me at this ratio in Lawn-Boys and other 2-cycles for 13 years. Deposits are minimal and there is never a need for exhaust port or muffler cleaning. I recently sold my 1994 LB 10201, and the compression actually felt higher than new - the front wheels would come off the ground when pulling the starter cord. This is one of the major effects of Opti oils - surface improvement by 'Eutectic' means. It definitely is not synthetic, being a paraffin-based oil. Plus, Opti oils are designed for air-cooled equipment where automotive products are not.

When I worked as a mechanic at a Buick dealership, some of the old mechanics would pour water down the carburetor VERY SLOWLY. The water turns to steam and the shock knocks off the carbon. When the old ladies would bring in those beautiful Buick Electras and Riverias because they idled rough,the Service Manager would take the car out on the freeway and really get after it. I went with him once and you could actually hear the carbon particles tinkling out the exhaust pipes. He would ask if they were burning Ethel as recommended in those 11:1 high compression engines. The customers jaw would jut out and they would say they will only burn regular. Idiots. I think adding transmission fluid to your gas would only carbon up your engine even more, if it did anything. Sorry off topic. I use Stabil and fill the gas tank to the top to prevent condensation from forming when I park my GT for the winter. (I empty my weedwacker,leaf blower and chain saw whenever they won't be used for several weeks.) Six months later the GT starts right up. I don't have any experience with SEaFoam.

Hey! The price of oil has reached 70 USD a barrel, and Brazil is about to reach oil independence, in Europe the price of a gallon is around 6 USD.... what can I say, saddly the americans don't seem able to think out of the box. Everyone complains about the price of gasoline in the US, but you don't realize that this low price make so that no real energy independence can be achived and no real environmental policy can be carried out. Ethanol by itself is not a solution, it is rather part of the solution. Ethanol can be used mixed in cars in mixies of E90 or E85. Making it compulsory everywhere in the US would reduce the oil import, meanwhile the farmes could benefit of this. In the same time the ethanol can be produced partly by using electricity, which in turn can be produce in nuclear facilities, so everything is produced in the US... More diesel can be more widely used in North America, the politicans should change this idiotic ban on diesel. Diesel means better mileage and smaller CO2 emissions. Also there is Biodiesel.... that can be produced in the US, so no more soldiers to be sent in Irak or anywhere else in the world. More just imagine a hybrid car, that instead of using a regular gasoline engine it would use a Biodiesel car and more, it would be plugable (http://www.hybridcars.com/plugin-hybrids.html), so even lower CO2 emissions and complete energy independence.... Just think of it... energy independence and the country that would be considered the cleanest and most environmental friendly. This would be somthing to contemplate....

OK, it's easy to get excited about something when there is no apparent reason to suspect that it may be a scam. Gasoline and Diesel fuel are actually both blends of lots of different hydrocarbon chemicals. Thats just one of the reasons we have computer controls that provide instant adjustment of air fuel ratio's and timing curves. Oh, and yes today's diesels are computer contolled we simply have to wait for the fleet to age and pass before the majority of diesels are computer controlled. IMO, no additive dumped in a fuel tank is going to make a significant improvement in the efficiency, and cleanliness of the older designs. No additive is going to improve today's automobiles. What you described about getting people into this "investment" has all of the appearance of a classic pyramid scheme. The only guarantee's about that are a few people will get some money, and some of them will return it (or at least some of it) under the threat of prosecution. Many will lose their "investment". Pyramid schemes are illegal, and for good reason. If there was any merit to this product, they would have no short list of people (with big bucks) interested in investing, and they wouldn't be looking for the "little guy".