kahnen

Here's two pics of some data for you. One is of stock(Or hope so, if the data you gave was correct, kv/gearing) the other is with the ezrun you got. As you can see, to get roughly the same speed as the stock brushless you'd need to gear up to 22/87 from what you got now 19/87. Now, weather the 380 sized ezrun can handle that you'd have to test.

If this is what you was trying to gauge if you were doing something wrong by?