Air filter question

hi was talking to a landrover enthuiast and he said if i took of my oil bath air filter and replaced it with a pancake type it would improve my mpg is there any truth in this

I've a blue cone filter, don't know about mpg but it's a lot neater and loads more space.

Sucking the air through the oil takes some doing. Sucking it through a piece of paper is a lot easier. More air into the engine makes a bigger bang and therefore more power. So in theory you should do more mpg but you will definitely have more bhp.

Would this work for diesels as well as petrol? I was looking in the shed earlier and came across one. I don't know if its for the previous petrol landy though

Sorry to jump in, I fancy putting a pancake filter on, anyone know what size diameter the filter connector is ?

Depends where you want to put it. Diesel? Petrol - if so which carb? I just got a cheap one here: RED JAP STYLE FOAM MUSHROOM CAR AIR FILTER/INTAKE UNIVERSAL CONE RACING SOUND | eBay

Not he best quality and they smell funny but a lot cheaper than a K&N.

Not sure, but you might need to tell your insurer as it _will_ increase BHP!

Also, unlike the oil bath, it will need replacing frequently to keep the performance increase a paper filter fully of crap is worse than the oil bath!

I've just got mine while I work out how to re-route from the DMTL carbs back to the oil bath

It doesn't have to suck the air through the oil, only the oil covered mesh to which any dust, grit, insects etc will stick - similar to the reusable washable K&Ns but using mesh instead of foam. Can't see it giving you much power increase on the standard carb if the filter is clean and the air pipe isn't collapsing inside. With a twin Weber you might.....

But surely, this will severely effect the vaccum advance system?
If it is alot easier for air to enter the engine, then there will not be enough negative pressure to build up a vaccum?

have bin told by a few that it would inprove mpg and throttle response dont no anything about vacum and negative pressure ,you lost me there it is 35 years old petrol engine

Take the pipe off the carb and see if it makes any difference. Its very damp at the moment so the engine won't inhale any atmospheric dust in the short term.

Don't confuse the large increase in induction roar with extra power!

The oil bath cleaners aren't generally considered restrictive.

I found it a pain to adjust my timing and mixture, before I refitted my air filter. It wouldnt accelerate properly, it spluttered and then died everytime. I ended up half covering the carb inlet with my hand to get it to accelerate.

oil bath causes almost no restriction on air, it works a bit like a dyson, the air is forced around a corner and the heavy particals hit the surface of the oil and stick. the vacuum in the inlet will not be a effected by removing of changing the air filter.

Hi I've done the above on my 73 s3 bit noisier but defiantly more responsive and needs little choke. I've connected the pipe from the top of the engine to a oil breather catch tank which I've mounted where the old oil bath filter was. Is ok to divert away from the carb ?

Home Guard said:

But surely, this will severely effect the vaccum advance system?
If it is alot easier for air to enter the engine, then there will not be enough negative pressure to build up a vaccum?

Click to expand...

The Vacuum connections are manifold side, after the butterfly, so no change.

If you're getting those symptoms you need to fix your carb not the filter.

It sounds like your new filter is _restricting_ the air flow more on the input side causing a greater vacuum in the carb. A bit like pulling the choke. You need to sort out your carb. Either your idle mixture is too weak, your accelerator pump is not working or your main jet is blocked, you have a vacuum leak (either manifold or round the butterfly spindle), or all of the above.

The vacuum advance will not be overly affected only slightly. Fix your carb / manifold first.

Bet it will be dam noisey though...the oil bath acts as a good air silencer.

I ran mine for a day or so a few years ago with the air filter disconected....made no diference...try it yourself.

Nick.