It may have been cheaper to just buy an XO-1. I have one on those and it truly does go 100 MPH all day long. If your ESC allows 6s, that is your best bet for speed. It will be MUCH faster with 6s over 4s!

Also, if you are just bashing on the street, experiment with MUCH higher diff oils, especially in the center--maybe as high as 50k or 100k, or even 200k to lock it down better via the high bite. Experimentation is part of the hobby's fun.