I called Moto-Tassarini today and asked all the questions. As we all pretty much know, the low setting adds low and midrange and the high setting adds a few RPM's to the top without affecting low end or midrange.

The spacer will add to low end but not affect top. Keep in mind that this is on the 400 motor. He told me that other quads, such as the Banshee, are affected differently by the reeds and spacer.

By the way Bill, you should notice some improvement with the Delta II's. They are worth it for the price.

That's strait from the horses mouth!