Andrew posted:

A lot of people in dusty dirty environs turn the head of the inlet to the rear to reduce the entrainment of crap into the air cleaner.. doesn't necessarily help the efficiency of the engine, but reduces the frequency of cleaning the element..

Sambo posted:

Yes snorkels are available for Prado, just had mine fitted to TD. I would have to agree as to your comments that the Prado is clear leader in Mid size 4wd. Cheers

Pathfinder posted:

mmm, yes, Prado is the clear leader if you don't mind complex, unfixable breakdowns (particularly of the electronic variety) in remote locations... I'll keep my relatively old-fashioned mechanically-controlled turbo diesel thanks...

Troy posted:

David,

what about a situation where a 4x4 has no snorkel - the air gets drawn from either inside the engine bay, or air travelling up via a wheel arch....

surely this "factory" setting limits air flow more that a backward snorkel ???? What about a donaldson ? snorkel manufacturers recommend them, and they also may be seen to limit airflow.

has anyone seen the amount of build up - water, dust, bugs - a donaldson pre-cleaner catches ? id prefer this crap (including water when it rains) not to go into my air intake.

It appears us backward snorkel travellers (most of the field in the outback challenge included) are part of the "dumb" brigade as you so eloquently put it.

Who moderates the moderator ?

Exploroz Team - David posted:

I can write what ever I want just as you can this forum is not moderated except for illegal or indecent material.I may not be a huge expert on every aspect of 4WD mechanics though I have only travelled around the country a few times, fully service all my own vehicles and had many many debates with others on topics such as this. Additionally I speak to suppliers and manufactures all the time. If it seems dumb to me and it seems dumb to others then how about a technically correct answer.As I mentioned turned around is fine for dusty conditions where prolonged exposure to dust would be an issue (such as the outback challenge - this is an extreme event and not something that you everyday 4WD is worried about). In reference to the intake internal to the chassis correct no forced air effect however no vaccum effect either (which I think is worse). As for water entering the air system I have driven for days through major tropical downpours and not even had any water appear in the water trap of the air filter. When you are stopped the water will not enter, at speed the water hits the back of the intake and runs out of the head before it even gets near the downtake pipe. As for dust entry I would suspect that the swirl effect of having the filter backwards could actually be worse (awaiting a techincal answer). Bugs, crap and dirt, well of you are exposed to huge amounts then install a pre-cleaner bowl head and not a snorkel head, I have never had that much junk enter that I would be worried. I am also very confident of fuel economy improvements in my vehicles with the snorkel installed to manufactures specifications.David

Flappan posted:

Andrew, geez if your going to quote people get the words right first.

The thread says it is WORSE to have it pointing backwards, better to have it fowards, and then explains what David has said above.

Troy posted:

Hi Grant,

ummm - yeah - looks by the reactions to my last post - it did come across a little aggressively - so apologies for that.

Economy not effected adversely for me with snorkel reversed.

will lay off the angry pills too....

Ken D posted:

Maybe its a little late to enter into this debate, buts here's some other spanners in the works to think about.- Can a rear facing snorkel reduce dust pickup, look at the back of your car after a dusty trip, low preasure areas appear to trap dust.- Further to this what if you pointed the intake sideways. Sound silly? Mercedes off road trucks have a sideways facing intake on top of the cab. I'm sure they were thoroughly tested. Other off road trucks have a raised air intake that turns and faces downwards at the top, effectively the same. - Heavier debris such as insects can't fly directly in. - All this aside, considering the airflow of the average 4WD at 100kph, say 4litre engine @ 3000rpm = 6000litres per minute, does the pressure created either way mater significally?- I just thought I'd stir the pot.-- Anyway gotta go. I'm of to rotate my air intake.--Oh ##*t which way? Help please.-
Cheers
Ken