One downside is, you may find the item only works in the inventor's or salesperson's mind and has no foundation in fact. The good thing is there are items that are low-tech, have been proven to save fuel, increase power, lower emissions, keep the engine clean and are installed on thousands of vehicles.
There is another downside though. Most systems only incorporate one aspect of the entire picture and cost about what you'll save if you have it on your car for a period of years. The upside is that it's possible to get all the proven, time tested items in one package and you can build it yourself for as little as $50.00 in parts, and build it one stage at a time when you can.
Recently, I read an article on www.ecospace.cc that talked about water injection. The problem with water injection is: true water injection, like fuel injection, requires pumps, injectors, regulators and cubic dollars. Anyone who has been involved with cars for a long period, especially race cars, knows that for a fact. Unless we have deep pockets, or are well established and funded in race cars, true water injection is out of the question. Water injection for race cars is first and foremost for horsepower. The average person has neither the need, the expertise nor money to build and install true water injection.
Water vapor, is a different situation. Most of us have experienced increased horsepower when there's increased water vapor (humidity) in the air as on a foggy day. I have a friend who's a retired CHP and he says he always gave more speeding tickets on foggy days. Human nature: if you've got it; use it! There's a reason for the increased HP and it equates directly to economy, read my post 'Efficiency Equals Economy' for the techy part.
Water vapor is reasonably easy, quick, safe and inexpensive to implement, but it's only one piece of the entire puzzle. If you don't have all the pieces, you only see part of the picture and can't get all of the possible benefits. The best way to learn something new, or explore someplace you've never been, is to have a guide that can show you step by step how it's done best.
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http://www.mileageman1.comLarry R. Miller has been a freelance writer since 1982. His main topics are health and fitness, travel, adventure and increasing fuel economy. He is a photographer, inventor, weekly newspaper columnist, full length book author and international Internet marketer.
Shenzhen Mody Tech Co.Ltd., built in 2018 and headquartered in Shenzhen Bao’an District, is an innovative high-tech enterprise focusing on E-cigarette research& development, manufacturing and distributing and offering OEM service.