Hi CARS,

Got pics of your big Chipmunk? I am not familiar with the E-flight motor or SH81s servos. If your motor is longer than the recommended Rimfire 400 28-30-950kV Electrify motor the cowl can be moved forward a little. Also there is about 1/4" clearance between motor diameter and inside of cowl. Firewall has 3 blindnuts located for the Rimfire 400 motor. The servo cutouts in tray and aileron mounts are snug fit for Futaba S3114 servo so you might need a little surgey to fit tthe SH81s. I suggest reinforcing the firewall with epoxy as motor vibration loosens the CA. Placebattery to get CG rather than put weight in the nose per manual. This thing is a joy to fly butlandings are a challenge in 15mph wind. Mine is set up for flaperons but has some right roll with flaps down for some reason I haven't figured out. Does nice aerobatics and I get 9-minute flights with 1200mah battery using mostly half throttle.