Quote Originally Posted by gorilla p View Post
....There has been a lot of tests done on this, although not many high profile. ....
I have no problem believing increased mpg - that's something that's easily verifiable. However, until someone does comprehensive LONG TERM testing, I wouldn't want any part of it. Fuel flows through a number of things such as pump and injectors. Exhaust takes a long trip through a bunch of stuff including the million dollar cat. Very few of those parts are cheap. Even presuming it doesn't bother any of the metal parts (and that would also need to be proved), just one thing like a fuel pump going South would zero-out all of the gain from the better fuel economy, even for a DIY.
But I'm a flexible guy, and if it can be shown to cause no damage to any parts for let's say around 15 years, then count me in