Here is a video of my old nitro rustler with the stock pro .15 and a stinger pipe. I thought it ran really well.
http://www.youtube.com/watch?v=TTv_QldDRUE
[youtube]http://www.youtube.com/watch?v=TTv_QldDRUE[/youtube]
I had a nitro firestorm with the stock HPI engine in it, and Im pretty sure this old nitro rustler was just as fast.
Eric