I'm new when it comes to gas engines. I have a Zenoah G-23 on my 1/4 scale Sig extra 300xs. I watched the identical set-up at an air show and it flew great. Mine is diving to the left as soon as it gets off the ground and I have to keep using right aileron to straighten it out. It's a real bear to try to fly. I'm lucky I havent crashed it yet. I have re-checked the side to side ballance and it's perfect. I have the back plate of the engine mounted to the firewall with a piece of 1/8 " thick rubber between for vibration. Is this engine thrust doing this? Should I add some washers behind the left side of the motor mount? I'm afraid to take it up again without figuring something out. Thanks for the help!