Chips don't destroy anything. The tuners are great too, but a 4 position chip is great as well. They are in fact easier to dyno tune than programmers. My chip allows me to have 4 stored tunes and I can still have the stock tune as well. Can change on the fly, too. To get the full benefit of a pulley, you will need a tune from either a chip or a hand held programmer. I am very happy with it.