Outer Limits 4x4 Board

Just found this relatively scientific test on whether it's better to mount your snorkel head forwards of backwards by measuring the pressure drop:

Scroll past the Espanol to the english section.
http://tucanviajero.blogspot.com/2011/0 ... -aire.html

Granted it's not the most scientific or clear where they take their readings from but it's interesting reading.

I run my snorkel head facing the windscreen. It is approximately 130 degrees from facing forward. I run it like this as a compromise between avoiding hang ups and disturbing air flow. I have no scientific data to prove if it works or not. All I know is it drives the same as facing forwards and I haven't hooked it on anything since I rotated it.

Just my 2c.

Cheers,

Micko

To summarise:
They found a difference of ~14 cm of H2O at 130km/h. The normal atmosphere is around 10,000 cm of H2O.

At legal speeds, it makes no difference at all. If you can do 300km/h it's worth pointing it forwards.

Not sure where your 1 Bar atmosphere number comes from or its relevance?

Theres not much result but its something, 0.2 PSI if I read it right, more than I thought there would be. Plenty of engines only run 10psi boost so 2%
This would certainly help overcome airfilter restriction, bends etc.

jetjr wrote:Not sure where your 1 Bar atmosphere number comes from or its relevance?

Theres not much result but its something, 0.2 PSI if I read it right, more than I thought there would be. Plenty of engines only run 10psi boost so 2%
This would certainly help overcome airfilter restriction, bends etc.

1 bar is atmospheric pressure. It is what is there pushing air into all those non turbo engines.
The maximum you can get at 100km/h is 0.4%. It's nowhere near 2% and to get that you need an intake the size of a rubbish bin to slow the air enough. Basically unless you can do 300km/h it's not worth the effort, all you will do is catch more bugs, leaves and dust.

Yeah, did the conversion myself rather than using the one from the document it amounts to stuff all, more like what I expected.

KiwiBacon wrote:

jetjr wrote:Not sure where your 1 Bar atmosphere number comes from or its relevance?

Theres not much result but its something, 0.2 PSI if I read it right, more than I thought there would be. Plenty of engines only run 10psi boost so 2%
This would certainly help overcome airfilter restriction, bends etc.

1 bar is atmospheric pressure. It is what is there pushing air into all those non turbo engines.
The maximum you can get at 100km/h is 0.4%. It's nowhere near 2% and to get that you need an intake the size of a rubbish bin to slow the air enough. Basically unless you can do 300km/h it's not worth the effort, all you will do is catch more bugs, leaves and dust.

Its like the great big intercooler scoops you see on some WRX's bonnets ... Now on paper they seem like a good idea .. cool the incomming air charge by an additional few degree's ... but the extra kilowatt or two generated does not offset the additional drag created by this new sail you have just added to the car ..

So in short the additional drag created by the snorkle will more than offset any small gains had at the flywheel.

These snorkels we sell for the Tritons and the Vigo's dont seem to have any noticable difference than a forward facing snorkel.

I would rather be running a precleaner

why not a Pod filter?

I dont think pre cleaners and pod filters would help a 4wd vehicle when a water crossing is involved.

By precleaner I meant a dust seperator that sits on top of the snorkel.

toaddog wrote:By precleaner I meant a dust seperator that sits on top of the snorkel.

My apologies i thought you were actually meaning not to use a snorkel