The stock ESC runs a stock motor fine (I raced with it, but in my TA05), you just need to relocate it from under the plastic plate, to get some airflow. However, the E10 isn't worthy of running a stock motor, it will chew the drivetrain to pieces. You'll have to upgrade to a TT01, TA05, cyclone S, TC3/4 etc. The E10 is the ONLY RC I would ever chuck. I only kept the front and rear bulkheads and suspension assemblies in case I might use it for a project.
HPI E-Firestorm - Tamiya TA05 racer (carbon chassis, 10.5 brushless etc) - LRP Blast S10 BX - Revo 2.5r truggy conversion (in progress)