I can tell you it's impossible to see even half or even a 4th of that claimed HP gain without adding alot more fuel and air. Those chips work on a forced induction application by delaying a wastegate to build more pressure but most turbo guys know it can be done more efficiently,have more precise control and in some cases cheaper than a adding a chip.
On any naturally aspirated application the chip fools a temperature sensor into pushing a little more fuel through the injectors but only at WOT,advances the timing a little and can sometimes add more pressure to the tranny fluid making it shift more crisp but this is just a general desciption and some things on a 4Runner might be a little different but it still should work thre same way on an NA vehicle.