So it's probably not necessary to go submicron. Can any of the veg chaps confirm Keef, RM?
as to microns of cars my understanding of it all is whats been written 10 down to 1m
i filter down to 1m but its not really 1m as (i cant remeber terminology) but 1m is only a loose form of micron, i think people sub micron due to trying to actually get 1m finished article. meaning people use 0.5m so if any error factor on actual micron 0.5 really ends up more precisely 1m more definately...
moving on to car filters mine are gone! i use sausage filter 40m? at a guess, this lets 100% thick veg oil through and stops rubbish and no need to change it ever, well not yet anyhooes done 1000's of miles so have another 4x vehicles and still going...
for veg oil 10 to 1m is too small for thick veg, how could you expect veg to go through something as thin as diesel can go through...