I am installing a Canton remote oil filter in between my oil tank and the engine scavenge inlet. I am doing this to eliminate the possibility of metal particles that have showed up in the past on the sump screen. There may have been some lurking in the tank or lines that never flushed out.
? what size filter would be adequate to filter and not hinder oil flow, a fine element 8-micron or a fine 140 mesh 150 micron screen, the oil pump is a turbo pump.

As I read your lengthy thread on the garage, you have a 914/6
Oil tank. I also saw your thread over on the Pelican engine forum. This tank has a filter built into it which cleans the scavenge side oil *before* it enters the tank. 2 filters on the scavenge side would be redundant. There is no filter on feed side nor should one be installed as there is no pressure to push oil thru it....it is suction/gravity feed only.

Did your shop ever discover where those metal bits on your screen came from? I don't need to know, but you do.

BTW, *very* nice job on the car.

They didn't it is still a ? mark.
The only thing i can think of is it may of been in there from past history before i owned the car.
The Canton inline scavenge filter i have is made for the suction side of a dry sump and would not be restricting the screen element is much like the screen on a sump. The problem with the stock filter and the stock engine thermostat as i understand is they have an oil bypass so the oil is not always getting filtered, so if i added the Cantan canister filter in the pressure side out of the engine i would be assured that
all the oil is getting filtered all of the time.

As I understand it, the only time a proper filter will bypass is if it is clogged. Regular replacement will keep that from happening....unless the bearings & other implements
self destruct, then it becomes moot.

That said, another filter won't hurt either....unless it becomes clogged.

I use a Canton filter on the scavenge side of my 914/6 track car. I do not use a stock tank in my car (so no built in filter there). I think of this filter as having two purposes:
1. catch garbage that comes out of the engine so it doesn't pollute the tank, cooler, etc.
2. I use the mesh screen filter, so it serves as a convenient inspection filter (easier than the Canton disposable filter elements).

As for flow, I believe I remember that when I bought mine 10+ years ago, Canton rated its filters at something like 40 gallons per minute of 180 degree oil in the large filters (not distinguishing between the coarse and fine filters, interestingly). This is way more than any 911 engine will need, so you're good there.

Scott