Thread: Round or square filter box

The square one looks nicer , but I think that is about it.
I have an RRC 3.9 with LRA snorkel and LRA side entry adaptor to the barrel air cleaner.
I have tested pressure drop with a Minihelic gauge before and after the MAF. Total restriction before the MAF ( snorkel , elbow, air cleaner)flat out in second ratio up the steepest hill I could find was about 11 inches of water which is very small.
Maybe the square one is better, I do not know, but until someone does a comparative test using correct pressure drop equipment, it is OK by me.

There has been quite a lot of debate about this in the past where some posters claimed it was theoretically incorrect to have a side entry, but there are Donaldsons with this arrangement, and only a couple of weeks ago I saw a photo of a Land Rover model(AFAIR 200tdi RRC or maybe VM,) that had one from the factory.
Regards Philip A

I'm not sure about the filters in all square boxs, but at least in the Disco2 the square boxs are prone to leaking dust past the filter.

Like Simon says, the square ones are worse for dust sealing. I'd mod your cylindrical one for the snorkel.
I had one on my 1992 Sherwood, and my 4.7 stroker definately wasn't wanting for air

JC

Square filters are for cars (i.e. vehicles not intended for service in dusty environments).

Well that pretty much says it all - stick with what I've got and be

As you have LPG I recommend you keep the cylinder air cleaner as it is more robust. The last time I fitted a snorkel to a RRC with a steel cylinder cleaner I purchased a nearly 180 degree bend hose from a wreckers and plumbed the air in from the front. I don't know if your D1 has enough room for that. Otherwise I have seen a large sheet steel adaptor hand made to fit a steel cylinder which had much more filter surface area visible to the inlet than the regular plastic adaptor.

I have a snorkel Fitted already it was just which was better

I have a round filter with the snorkel plumbed into the front.