I built this one for a Friend a couple of years ago, it's a Bruce Tharpe Delta Vortex. I believe these two deltas have the same dimensions & power requirements. In the BT manual it says top speed is just over 90 mph in a dive using a .91 engine. I used the OS .91FX. This delta is a floater & easy to land but crack the throttle open & she moves faster than most sport planes, unlimited vertical with this engine. I forget what prop I used, might have been a MA 14x6. I remember adding an ounce or two of lead on the tail to balance.I used two rudder servos so I could deploy the speed/dive brakes, both rudders will deflect outward. I remember setting up a couple of mixes to get the rudders to deflect outward without it affecting the steering gear. The radio I used was the Futaba 8uafs. Hope this helps.