Just snake oil.... You'll gain more by keeping your tires inflated to the proper pressure. Really, what's a 1" spacer going to do? If that 1" really gained anything like the 14 foot pounds torque, don't you think that Toyota, with one of the best research facilities in the world, would have already built that in? SNAKE OIL! In fact, real snake oil added to gas would probably do as much good. Hey, but if you're into lame eyewash, go for it. Yellow stickers make horsepower too....depends on who you ask.