How does altitude affect performance?
Elevation has a very noticeable effect on the wide-open-throttle (WOT) power of an engine. Since air gets thinner as altitude increases, the engine begins to starve for air (oxygen) and horsepower is lost. If the boat has been set up at a lower altitude and then moved to a much higher altitude, there will be a noticeable reduction in power, thus rpm. With Stingray’s efficient z-plane running surface, a drop in propeller pitch of 2″ to 4″ will usually solve most altitude problems. Many boats without z-plane hulls require an outdrive gear ratio change to operate at higher altitudes. However, this fix is only safe at higher altitudes. If the engine is again run at a lower altitude, the gear ratio change must be reversed to prevent excessive engine rpm and excessive torque on drive train parts. Any boat with a high altitude gear ratio has a restricted range of operation compared to one only requiring a different prop when changing altitude.
