Good you went to hotter plug since it rained. heat ranges changes timing of engine, and depending on % of nitro. What fuel are you using? Good you get away with AA & D igniters. GLARCRC guys use the Sub-C Igniters, Mine Sub-C igniter uses a 1100mah battery, I use a 3800mah tenergy battery, it last longer & a hotter glow(bright yellow) of Glow Plug.