I guess that really depends on where you live. Here in Utah, we regularly drive up to 9,000 and 10,000 feet. The air gets pretty thin and where you guys have 500 hp down at the beach, we have considerably less in the mountain air. When we drive up Mt. Nebo, there is a very noticeable difference in how far you have to push the gas pedal. The little blocks just lay over on the hills at those altitudes and beg for mercy.