I am exploring the idea of having my blower rotors coated along with the inside of the case. My blower is a 177 weiand but my concerns would cover most blowers. these are my thoughts and concerns: First : The coating would decrease clearances which I believe would produce more boost at a lower blower speed. Lower blower speeds means that the air is not heating up thus making it more effecient. My concern is that the coating on the inside of the case would also trap what air is heated by insulating the case. Also, would the coating chip or worst case , seize the rotors if they ever came into contact when they expanded. I am talking to a company who says their coating have zero clearance because the coating they use will wear into its place as the rotors expand creating a tight seal. What wears off goes thru the motor with no ill effects. What are you guys thoughts on this?