Any of our custom car computer packages should work well in this application, even at 115 F. The Intel boards with heat sinks and fans (GCLF2D) might be a wiser choice, as moving air could help keep the temperature lower than non circulating air. One thing we've experienced (and something to avoid) is that mounting computers in the direct sunlight can increase the internal temperature of the unit beyond the 131 F temperature very quickly, even if the in car temperature is below 115 F. Normally this isn't an issue in an automotive install (i.e. install behind dash, under seat, etc.), but be sure the panel where you mount the computer doesn't have it's own heat source (i.e. engine, exhaust, etc.).
Please let us know if you have any additional questions.