Thinking about going from an L2502hst to a L3902hst. Looking for more power. At almost 5000 foot elevation with hills and it always feels like the little engine that could. Considered maybe modding the 2502 to get some more power but not really into voiding warranty for questionable mods in search of power. Figured its better tp upgrade. Wish I would have just got the 3902 to begin with.