This is the only air filter I can fit. Is it too small?

[stirlsilver]

Hi all, my land rover has the 3.5L V8 fitted and I currently have a finer filter foam filter on the engine and it is FAR too small for the engine. So I'm currently looking to change this when I fit a LPG mixer ring that I designed (I hope it will work better).

I dropped into a place that sells donaldson air filters and I was taking various filters out to my car in the carpark to see where the hell I could fit one of the monstrous things.

After about an hour hunting around my car, I found the only place I can fit a filter is inside my wheel arch because there is absolutely no room in the engine bay (It's either there or a large donaldson filter on the tray but the plumbing would be an absolute nightmare). Anyway, this is what will fit in the wheel arch:



Obviously when choosing an air filter you have to maximize the CFM and minimize the pressure drop. On my car, I unfortunately don't have the luxury of space.

I just want to know what you guys think. Is 232 CFM @ 10" of water far too small?

[want33s]

I think 232CFM will choke the life out of it....
The bigger the better as far as filters go....
Have you thought about using two flat element filters. EG 240 Volvo.. Cheap and readily available.
Here is a pic .. Porsche actually.. but very close..

[Santos]

Do you have a snorkle? You could mount a light truck type filter externally.

I'd say that going to a self-serve wreckers with a measuring tape and check all the v6 family sedans/wagons for something of the right shape might be a better bet most a 3->4.1L

[stirlsilver]

I do intend to fit a snorkel, and I did toy with mounting an external filter, but 1 it would look incredibly ugly and 2 if I mounted it on the side (something that is 10" diameter) it will be the first thing to be smashed when off road. I think i'm going going have to make my own air box... Then again your suggestion Santos might be a go too.

Going to have to give it some more thought I think.

[-Scott-]

Just did some quick calcs in Excel.

Ignoring pressure drop and volumetric efficiencies and any other real world effects, at 3000 rpm your engine is trying to pump 187cfm, at 4000 rpm you're up to 250 cfm.

I'm not sure how these figures relate to realistic real-world performance, but I think (as you appear to have concluded) that a 232 cfm rating would be inadequate.

[droopypete]

I would think that anyone who has the resources and ability to make their own LPG mixer ring, would have no trouble making a cracker air box that fits the cheapest, most common, most efficient filter available, good luck with it and don't forget the pics.
Peter.

PS, maybe make detailed drawings for repetition (there may be a market for them )

[stirlsilver]

I would think that anyone who has the resources and ability to make their own LPG mixer ring, would have no trouble making a cracker air box that fits the cheapest, most common, most efficient filter available, good luck with it and don't forget the pics.
Peter.

PS, maybe make detailed drawings for repetition (there may be a market for them )

Cheers for the suggestion Peter. It's something I may actually have to do like you say. Just going to be a pain.

Scott, thanks for doing those calcs. While 250CFM is close-ish to 232... the whole problem is that it's at 10" of water pressure drop. Probably way too restrictive.

Grrr, another custom fabrication job it seems.

[KiwiBacon]

Scott, thanks for doing those calcs. While 250CFM is close-ish to 232... the whole problem is that it's at 10" of water pressure drop. Probably way too restrictive.

Grrr, another custom fabrication job it seems.

10" of water is only 2.5% of an atmosphere. That's bloody good really.

[stirlsilver]

You're right... about 2500Pa. Hmm, maybe I'll get it. Thing is, I wonder how it compares to the finer filter I currently have fitted on the engine:

[KiwiBacon]

You're right... about 2500Pa. Hmm, maybe I'll get it. Thing is, I wonder how it compares to the finer filter I currently have fitted on the engine:

Donaldson vs Finer Filter?
What was the question again?

[Gwagensteve]

I can't see an air filter in your picture....

Steve.

[ISUZUROVER]

Stirling, move the lube bottle and LPG evaporator out of the way and you will have room to fit the biggest filter you can dream of - e.g. the donaldson filter that was factory fitted to a stage 1 4BD1.

Failing that, an RRC or disco barrel-shaped filter housing with the trumpet chopped off will fit with room to spare.

If you can squeeze a Tdi filter housing in, all the better, as they have about twice the face area of a v8 one and an integral cyclone. The standard element is made by coopers, but donaldson make one the right size as well.

[stirlsilver]

Knew you would eventually find this one too ben

I'm not a huge fan of shifting the LPG evaporator at this stage as when it was installed a bracket was welded onto the chassis to mount it. If I move a few other things out of th way (like the cylinder head lube) I may be able to fit the bigger powercore donaldson filter in there:



Thing is this one is $300 Hmm.

Car is off the road at the moment with some nasty brake issues so I think I'll just get everything I want to do to it done all in one hit.