You need to dilute it.....we used 60/40 at my track, but I've seen up to 70/30 (methanol/vht)....
As for sprayers.....you got two options, be lazy......and just buy a new one when it stops working or, go through a VERY through cleaning regimine every time you are done. We used mineral spirits to eat it away, but I know others used acetone or denatured alcohol....it's a messy dangerous process.
If you want to make a lot of friends, spray way too much coming out of a sharp corner, where amp draw is nutty......ESC shutdown will happen after a few laps....everyone will love you.
Later EddieO