I have a stock oil tank with an aftermarket oil filter mount. I know that the ones some recommend have too large of an opening for the screw mount. The one that was on it before and the replacement are P-65, but pelican does not list this size for replacement, only OC-61 and others. I am confused as to what size I need. Help!

Weird. I didn't know the mounts were ever made by anyone else. Measure and I'll let you know (I have one of each). If some are too big I would guess you have the early style that is stock for a -6 or say... a 1970 911

I got my mount kit from Rich Johnson that also makes the /6 engine mount that I bought. Nice guy, good stuff

small thread oc-61 is the one you need for a factory -6 tank.
big thread oc-54 is the late 911 or vellios i think uses.
there is a 73 911 oil filter adapter that is like the -6 and early 911, but has the big thread, kinda rare.

what you have , dunno ?

(dig through your rubble pile and find the man some hot P&C's and cams!)

Shut up monkey boy! (Eric)

I'll measure the opening and look at the threads. I think it will be stock /6 and that the big ones I have found were for the later 911. The filters I had were from a parts stash my friend left me.

I've seen OC 54 and OC 61 on -6 conversions. I don't remember which filter fit which type of tank because I didn't need to know so I didn't look. I wouldn't remember anyway cause I can't remember shit, so I write it down when I remember to.

I just ordered from Pelican the OC61 to fit my DW Design tank. I was told the DW tank takes the OEM OC61 filter. I guess I'll see when they show up as I haven't installed the tank yet.

The tank doesn't take anything. The filter console that mounts on the tank does.

Click to view attachment

The Vellios tank, it screws right to the tank. No adapter.


OC54 has 25mm threads
OC61 has 19mm threads

OC61 it is. I measured 17.88mm on the inside diameter of the filter, but the threads will of course be larger. AND, printed on the base of the filter was 3/4 (= 19mm). The others that I tried had to have been the 25mm because they were huge. Also, I was a bit stupid in that I was trying to get a 74 filter for my engine not realizing until now that the tank is a 70 (DUH).