The low elevation kit comes with a clutch kit and a tunnel mounted heat ex-changer, also use's a pulley set up for less boost. ( mountain kit does not)
I just bought the mountain kit and I'm using it between 2800ft and 5000ft for most of my riding with no issues even though the pulleys are geared for more boost. The waste gate is set at 5psi just like the low elevation kit so all is safe, wastegate is just open more often. love it !!
I would recommend using more oil in the blowers oil tank and installing a puke tank for the overflow as many have burned up the blowers from lack of oil, especially in frigid temps.
