The pilot stated that the flight planning indicated the time en-route to be 3.0 hours, which allowed for a 45 minute fuel reserve. After takeoff the flight remained at 1,500 feet until clear of Special Flight Rules Area (SFRA) at PALEO exit Gate, then climbed on course to 7,500 feet mean sea level (msl). Course deviations en-route due to weather occurred, and when the flight was 15 nautical miles south of Portland, Maine, he descended to 5,500 feet msl and continued at that altitude towards the destination airport until, "…indications of pending engine failure at approximately 10 NM northeast of Portland." He established best glide airspeed, declared an emergency with air traffic control and confirmed the distance to Portland and his destination airports. He proceeded towards another airport (Farr Field Airport) and flew over it at "High Key" position, or over the runway, and turned east for "Base Key." While on final approach he maneuvered between trees and touched down on runway 32. After touchdown he intentionally applied left rudder and brake to avoid runway overrun into water past the departure end of the runway. After coming to rest, both occupants exited the airplane; the total flight duration was reported to be 2 hours 45 minutes. The pilot reported there was no preimpact failure or malfunction that would have precluded normal operation. During the accident sequence, the airplane sustained damage to the firewall and left side of the aft fuselage near the tailwheel assembly. Postaccident inspection of the airplane by a Federal Aviation Administration airworthiness inspector revealed the fuel tanks were empty and were not breached. A copy of the FAA Inspector Statement and photographs depicting the damage are contained in the NTSB public docket. The pilot further stated that factors that resulted in increased fuel consumption for which he did not take into account included a recent propeller change which increased engine rpm, fuel consumption planning for the accident flight based on a previous flight flown at a higher altitude and less weight, and finally course deviations.