Thread: Air Filter Tests (Finally)

My understanding is that Donaldson specify air cleaner capacity on the basis of achieving required flow at 80% of dust capacity. i.e still meet the required needs when 80% clogged. This is why a lot of people think the Donaldson spec. is over-large.

However - a german filtration engineer once said to me - they have a saying over there: Schaum ist Scheiss (schaum = foam)

I also would like to see a test of a properly oiled unifilter.

I fitted socks into the top of my Snorkel on my recent trip to the Kimberleys as a pre cleaner and they had a similar appearance to the one shown.ie red on side clean the other
My main paper filter lasted the whole trip and I only changed it last week, and it had NO red staining at all.

I have been loath to take the chance on a Unifilter even though I have spoken to the MD who claims that his oil formulation will not migrate to the MAF like K&N fluid. K&N is thin, Unifilter oil is very sticky and viscous.
Regards Philip A

I don't know why anyone would seriously think a 3.9V8 would draw more air than a tdi. When you think about it, a tdi has no throttle and so is drawing maximum air all the time. With boost at 1 bar (1 atmosphere), the volume is actually double - equivalent to a 5 litre petrol V8 at full throttle!
So it makes sense that the Land Rover engineers use a larger air filter in the tdi.

Yes , you can come undone on that.

I have a Donaldson Topspin at home which I tried on my 3.9 and the thing just slowly turns at light throttle openings, and achieves nothing.

Or have I said that before? What was your name? What are we talking about?

Regards Philip A

I have considered using a K&N filter based purely on the fact that I used these on all my cars for thier performance benefit, beit that I serviced them quite frequently, thinking that this would also apply to my Tdi.
Im not big on facts and figures and I can't give you the plutonic weight of a grain of sand on venus, but to what degree is the filtration vs efficiency vs performance etc going to effect my diesel engine if it spends most of its time in normal every day conditions with for arguments sake a K&N filter over an OEM?

Was this filtration test reflective on day to day driving or dusty road conditions?

Im just trying to grasp every bit of info from this thread as i can, Im new to diesels and found this to be quite an interesting read.

Ok, so all technical jargon and big words put aside, the bare bones of this whole deal is the only filter I should use in my 96 Disco is the OEM (or equivalent) panel filter? After all, the manufacturers know what they are on about, right? LOL

C&B

Craig

simple

on a bright sunny day hold up your foam filter and have a look through it. see those ****** of light.. thems holes.. stuff comes through them. Stuff that when mixed with oil makes grinding paste. hold that thought

do the same with a paper element filter.


now take the intercooler to turbo or the intercooler to inlet manifold hose off of your engine and wipe your finger around.. see how its black thats oil....

add that thought to the previous thought.








I dont know of too many manufactures that reccomend putting grinding paste into your engine.

your call on choice of filter.

Yep thats kinda what I got to thinking, which is the conclusion of my last post.

With the OEM panel filter, I'd imagine that the manufacturer would have balanced filtration and air intake to the most efficient level possible, which in my Disco is a panel filter.
So why would a manufacturer find in neccesary to fit a barrel type filter with pre cleaner and secondary filter if a panel filter is deemed satisfactory for others? Are these filter variances determined by cubic capacity of the engines, induction volume or supposed intended use of the vehicle by the manufacturer? Im not downing opinions, but if one was more effective than the other, then why isn't it uniform across the board?

cost, room, advances in filter construction.