heres what I have found on euopean vehicles with bosch VE distributer pumps, you can run 100% oil all the time, the injection timing definitely needs tweeking and also the delivery of fuel from the tank needs to be a single feed and a looped return. Idealy the feed from the tank needs a coolant heated filter, I have found this works as a heated swirl pot for fuel before it enters the fuel pump loop. the looped return works especialy well for two reasons, warm oil does not return back to the tank it recirculates round the fuel pump and the second reason is that the engine is only pulling what it is using from the tank rather than returning huge amounts back to the tank. it does have its down sides, purging the air out can be a nightmare but I will be fitting a three way valve to the loop so that during the event of a filter change I can swtch the loop to a full return and purge all the air back to the tank, this will also be good if your running diesel aswell. its very important to note that rotary pumps hate thick mixes, over hear we have lucas cav pumps that last less than a mile on anything other than real juice. all in all, if you have a bosch VE distributer pump attatched to your engine you could colstart and run on unrefined animal fallow, I have perfected my setup now and all that is needed to run 100%wmo below 0*c is a small shot of ether to take the load off of the starter.
