Thread: Keeping Bugs out of Safari Snorkel?

Originally Posted by shining

We use black stocking socks to filter the lint out of the laundry water for our greywater system. Yeah they would be great over the snorkel and hardly noticeable. Great idea Mr Knight.

You could start a theme here, I used one of my wifes red bra,s on my sand flag accros the simpson once

connock

I'm not going to post photos....not on this site anyway :-P

Intake air pressure sensing can but not always occurs both pre and post turbo so you get a comparative measurement of the actual boost pressure (ambient vs pressurised air). So it will make no difference at all.

Originally Posted by clubagreenie

Intake air pressure sensing can but not always occurs both pre and post turbo so you get a comparative measurement of the actual boost pressure (ambient vs pressurised air). So it will make no difference at all.

I agree, I can't see a relatively clean forward facing snorkel head with either panty hose or a Uni Filter type sock having any less air pressure than the standard guard entry because it is not facing the airflow.
I can see how a rear facing snorkel head should not be used at highway speeds because of the negative suction that is created.

Yes it is important to keep it clean but none less than the standard air filter.

Originally Posted by ~Rich~

I can see how a rear facing snorkel head should not be used at highway speeds because of the negative suction that is created.

I was driving a D3 with OEM Raised Air Intake (rear facing head) recently in Germany at 105 MPH for over an hour on an autobahn ... no problems at all with "negative suction".
cheers

You don't, well actually you do, create an area of suction but it's not suction back up the snorkel. The best analogy is the slipstream created by a car, probably best described by NASCARs simplicity. Their only goal is to make as clean as possibly hole in the air. You need to move the air smoothly as any turbulence is drag but you need some turbulence across the surface to prevent excess laminar flow and friction of the air on the surface slowing the car down.

But it's what happens behind the car that's important in relation to the snorkel. A lot of race cars will have a diffuser which creates too much turbulence to aid any but those cars following extremely closely and a wing to create physical downforce. The NASCAR only has a spoiler (vs a wing). The rear window of the cars is quite steep so as air passes over the trailing edge of the roof and this creates a separation of the airflow over the roof. Some will continue straight back possibly falling slightly while the rest will tumble down and create great turbulence and so form a lower pressure area in the depression at the bottom of the window/forward edge of the boot lid.

The spoiler at the rear edge of the boot lid lifts the airflow over the rear edge so the flow off the roof sees a gentler slope on the window and delays separation and reduces drag.

Whats important to note is at no point is air "vacuumed" or put into a point of negative pressure (there is the low pressure point but this is a reference pressure, it's simply lower than the air under/around the car). What does occur is that the air behind the rear facing head is it slows down and drops in effective pressure (this has just given me a thought that the air slows down and anything in the air will start to fall out of suspension). So what there will be behind the head is a low pressure.low flow area of air that is simply waiting to be sucked into the head just as it would be with the head in any position with the vehicle stationary at idle.

So some say sock (or possibly bra, undies or stockings) would be ok... Others not. I think i will go with the guy that i tried to buy a sock one and told me not to due to the turbo. On digging a little further into the unifilter support information on the internet it also states to only use the sock off road and at low speeds... So that sort of rules it out for road use.

I cant work out the effect of a rear facing snorkel on the air pressure into the engine.. So i probably wont risk that either.

I think the safest solution is to point the intake sideways. That is most similar to the original guard intake. Hopefully most of the heavier bugs will then simply fly past the intake. It will look a little odd facing that way though..

Any thoughts on that conclusion?

Ahhh...

Sideways WILL have an effect on flow into the snorkel, a detrimental one at that. It will create a venturi effect at the inlet of the snorkel and reduce (or at worst stop) flow.

Rear facing at highway speeds with or without a cover of some sort will have no change in the flow of air into the engine apart from the (minimal) positive pressure that having it forwards at high speeds will achieve.