While running on WVO seems like a great money saving idea, it is not anywhere near as good as many people make it out to be.
First off, the WVO contains all sorts of impurities. This results in carbon buildup inside your combustion chamber. No big deal, right. Well, the piston rings stick in the grooves and fail to seal. This results in massive blowby, causing the oil to be contaminated. It also causes the piston to overheat and stick in the bore, causing bore damage.
The motor oil will polymerize and eventually fail to flow, if you don't change it often enough.
There are plenty of poor souls who went this route and had massive engine trouble. There are many others who made it work. After much study, I am not convinced there is a "secret" to making it work. It depends on many factors including the age of the engine and it's health, the length of the trip, how often the oil is changed and the type of oil used. The quality and type of the WVO. The list goes on and on.
The top pic is a BRM engine using WVO
The bottom pic is a BRM engine with 100K on diesel.