Snorkel caps facing forward...why?

[jnaut]

**warning, sensibilities and dearly held beliefs may be offended, read at your own risk**

A friend and I were talking about snorkels on 4x4's, and we began to wonder why the caps always faced forward. It seemed to us that facing it in reverse would make more sense, that way rain would stay out of it when driving through it. However, when I got on the web, I heard mutterings about getting a 'ram air' effect. Ahem, as we "know", ram air is a myth, so why do the snorkel caps face forward?

 

[Ry' N Jen]

Next somebody is going to say that cowl induction hoods dont work either!
Snorkels primary design is to suck air from above the stock air box. Why? To suck clean dust free air when operating a vehicle in extreme Dusty conditions. And when crossing water that is deeper than the vehicles factory air box.
Weather it "works" or not as read in an article by a bunch of Vette owners who park their cars when it rains (Cause a: they don't want it to get wet. or b: Can't drive it because it doesn't get any traction in the dry, let alone when it's wet outside)

Look at the 2009 Dakar Ralley. All the leading Manufactures have a factory snorkel mounted with foreword facing opening!
But hey, what does BMW, VW, Mitsubishi, too name 3 know about it. Must be just for looks!

 

[Atrus]

Next somebody is going to say that cowl induction hoods dont work either!

There is no ram air effect on a snorkel. By the time the air hits the intake, all the bends and curves of the intake have killed any ram air effect. On a RWD car (Vette, Ram Air Trans Am, EVO, etc) the hood scoop dumps directly into an air box that dumps directly into the intake. That gives a ram air effect.

My Grand Prix had an SLP ram air hood. The airbox was where the battery is on the KJ. Air had to do almost a 180* bend to get to the box, then cut across into the intake. Numerous tests and studies were done within the community and it was determined that the hood made no difference. Looked good though!

So, I agree, I see no reason for it to be forward facing for a "ram air" effect. My only question would be if there's a "reverse" ram air effect at higher speeds that may hurt performance if it's backwards. Cowl induction hoods are successful because there's a large positive pressure point on the windshield at higher speeds. With nothing behind a backward facing snorkel, perhaps there'd be a vacuum?

 

[jnaut]

Next somebody is going to say that cowl induction hoods dont work either!
Snorkels primary design is to suck air from above the stock air box. Why? To suck clean dust free air when operating a vehicle in extreme Dusty conditions. And when crossing water that is deeper than the vehicles factory air box.
Weather it "works" or not as read in an article by a bunch of Vette owners who park their cars when it rains (Cause a: they don't want it to get wet. or b: Can't drive it because it doesn't get any traction in the dry, let alone when it's wet outside)

Look at the 2009 Dakar Ralley. All the leading Manufactures have a factory snorkel mounted with foreword facing opening!
But hey, what does BMW, VW, Mitsubishi, too name 3 know about it. Must be just for looks!

Sorry, I didn't find an answer to my question. Why? Because we know it's not RAM air, despite some web claims. Just because manufacturers "do it" doesn't answer the question, except to say "because they do it".

That's not an answer, that's an appeal to authority.

 

[Ry' N Jen]

Sorry, I didn't find an answer to my question. Why? Because we know it's not RAM air, despite some web claims. Just because manufacturers "do it" doesn't answer the question, except to say "because they do it".

That's not an answer, that's an appeal to authority.

Have you tried to contact the compay or companies that manufature these snorkels ans have them back their claims?

You will notice, that I said in reference to Dakar, "That it must be for looks" I also stated what snorkels are primarily for is for dust and water crossing.
Buy what ever.
Have a nice day

 

[jnaut]

So, I agree, I see no reason for it to be forward facing for a "ram air" effect. My only question would be if there's a "reverse" ram air effect at higher speeds that may hurt performance if it's backwards. Cowl induction hoods are successful because there's a large positive pressure point on the windshield at higher speeds. With nothing behind a backward facing snorkel, perhaps there'd be a vacuum?

That's what I was wondering about. If turbulence would create a small vacuum behind the snorkel. I linked to the Ram Air Myth article because I knew people would get their hackles up over ram air, and literally forget my question about the snorkel.

And, as I feared, I'd have to slog through "because x and y do it" answers. I know that x and y do it, and I'm asking why. The closest answer I came on the web was "because you want the ram air effect, man!".

 

[jnaut]

Have you tried to contact the compay or companies that manufature these snorkels ans have them back their claims?

You will notice, that I said in reference to Dakar, "That it must be for looks" I also stated what snorkels are primarily for is for dust and water crossing.
Buy what ever.
Have a nice day

I haven't seen any claims, except by users, they just build them that way. Can you link me to a claim? I can't find any.

I can find people who talk about it being a ram air, but ram air has been debunked a 1000x over, but people aren't willing to give up their cool looking hood scoops and what not. Most performance gains by fancy intakes are attributed to cooler air being taken in-- ie, the air taken in is way outside of the engine compartment.

Ram air has developed a kind of flouride-in-the-water mythos. So I ask again, is there any problem with pointing it backwards? Or is there a reason other than "ram air" to point it forwards?

 

[JeepJeepster]

Seems to me like youre getting a little to excited about the whole matter.

IMHO, no, there is no reason other than 'ram air' to point the snorkel forward. The amount of rain that gets forced down the tube should easily drain out in the air box so that shouldnt be a problem. If you have the end of the snorkel pointed right at the filer then it may get wet.

If you pointed it backwards I would say there would be a mild vacuum created which would make the engine 'pull' the air in where if it were facing forward the air is there to be used by the engine.

Sure, there are many turns and bends before it gets to the engine but with that slight positive pressure from the air rushing into the opening then its not being pulled into the opening. It may not force air into the intake but it lets the intake get the air it needs easier.

 

[Ry' N Jen]

Why would there be a problem pointing the air in-take backwards?
Doesn't "Look" right
Either way that "Air scoop" for lack of a better name will still sepparate the water and air allowing for only just air to enter the system.


I've already dismissed buying a snorkel kit from Australia because they simply cost too much. Depending of which one I buy and if I buy it directly from Australia of purchase via the USA they will set me back between $500.00 and $875.00. I can think of alot of other things to buy with that money, Like a new LSD for my Mini.
If im so inclined,
I can make a better one which will flow more air and uses a "K&N" type cone air filter at the top.., allowing me to remove the filter ellement from the air box.
Onlt thing is that I'd use a six inch aluminium tubing and it would probably look a little odd and out of place.

 

[Atrus]

Onlt thing is that I'd use a six inch aluminium tubing and it would probably look a little odd and out of place.

You can make one with black plastic sewer pipe. I forget what it's called, but I made part of my intake on my Prix out of it. Home Depot/Lowe's has it, sold by the foot I believe. Use that with some rubber plumbing elbows to put it together I think it'd look halfway decent.

 

[jnaut]

Why would there be a problem pointing the air in-take backwards?
Doesn't "Look" right
Either way that "Air scoop" for lack of a better name will still sepparate the water and air allowing for only just air to enter the system.

I think it looks better too. I didn't want to look like a dumb a$$ driving down the road with the cap on backwards, but I was looking at a mfg's cap diagram and it had this fancy drainage system with little animated raindrops. That's when I thought... why don't you just turn it around?

I've already dismissed buying a snorkel kit from Australia because they simply cost too much.

Plus, doesn't the vortex of air spin around the opposite direction with Australian Snorkels?

*pause for humour to set in*

But seriously. One of the reasons I was asking is a friend and I were talking about what it takes to home fab up a snorkel and were looking at others who had done various versions. Some people bought commercial caps and stuck it on their homemade snorkel. One guy used a vent from a stove which, while looking slightly ghetto had that road-warrior look to it. Anyhoo, we got into a discussion about being careful to not restrict air flow-- which is something I wouldn't want to do. That's when the forward vs. backwards question came up.

Like a new LSD for my Mini.

Is that legal in Canada?

I kill me.

 

[jnaut]

Seems to me like youre getting a little to excited about the whole matter.

Actually, I'm not. Just that inquiring minds want to know.

If you have the end of the snorkel pointed right at the filer then it may get wet.

That was one of my worries. Especially if I'm fabbing up my own.

If you pointed it backwards I would say there would be a mild vacuum created which would make the engine 'pull' the air in where if it were facing forward the air is there to be used by the engine.

I said that to my friend, and he responded "so when you stick your head out your window, and turn it backwards, can you still breathe?"

 

[Atrus]

I said that to my friend, and he responded "so when you stick your head out your window, and turn it backwards, can you still breathe?"

Ask you friend if he opens his mouth like this - - and then tries to breathe. I really feel there will be a vacuum, although it's probably immaterial in magnitude.

 

[Atrus]

Oh, and if you don't mind a little noise, why not pipe it into the cabin through the firewall? That's the best snorkel system yet. If the filter gets wet with that setup, you have bigger problems than a wet filter!!!!

 

[Ry' N Jen]

Plus, doesn't the vortex of air spin around the opposite direction with Australian Snorkels?

Carful now or them there Aussies are gonna think we're really screwed in the head here in North America!

As far as LSD for My Mini, One out of a Jeep won't fit!

 

[jnaut]

Oh, and if you don't mind a little noise, why not pipe it into the cabin through the firewall? That's the best snorkel system yet. If the filter gets wet with that setup, you have bigger problems than a wet filter!!!!

There was a guy crackin' wise on the web (can't remember where) where he was talking about hooking up a leaf blower to his engine to increase his horse power. He lost 5hp when he did it.

 

[Atrus]

Carful now or them there Aussies are gonna think we're really screwed in the head here in North America!

As far as LSD for My Mini, One out of a Jeep won't fit!

What do you have in the mini? 4.22?

I picked up a great-looking 3.90 for my Healey from a guy this summer for $40. Learned the hard way that the pinion seal drips, but that's an easy and cheap fix. I've seen them going for $300+ on ebay as of late.

The 3.90 will make cruising more enjoyable (when compared to the 4.22). I also hope to get a Datsun 210 5 speed and use the Rivergate conversion kit, which will make it cruise smooth as butta.

 

[Ry' N Jen]

What do you have in the mini? 4.22?

I picked up a great-looking 3.90 for my Healey from a guy this summer for $40. Learned the hard way that the pinion seal drips, but that's an easy and cheap fix. I've seen them going for $300+ on ebay as of late.

The 3.90 will make cruising more enjoyable (when compared to the 4.22). I also hope to get a Datsun 210 5 speed and use the Rivergate conversion kit, which will make it cruise smooth as butta.

I've got a 4.3 and then almost everything lower.

 

[jnaut]

Ok, new question my friend just hit me with.

Stock kj can ford water say, just below where the intake is above the headlights. However, even if some water gets in to the air box, the box is pretty well designed to drain before it takes it into the intake. But with a snorkel connected, one is now capable of fording deeper water. Is it advised to block the drain hole in the box so it doesn't fill with water through... the drainhole? Or is that not a concern?

 

[snowsport]

If there's a hole, water will find its way in, but how much, how fast is another thing. If you're submerged for extended period then you might have enough water seep into the drain to cause the engine to aspirate it. Guess it's all about how big the hole is. Maybe you could add a spigot or petcock valve where the drain hole is, open it when you're not fjording, close it when you are?

This forward-facing/backward-facing thing is interesting. Be interesting to see a wind tunnel with smoke or whatever, and see how the airflow breaks over the intake in both positions.

What about side-facing intake? That could be just a cutout on the body of the snork, with a rain hood. Wouldn't need the cobra-head-shaped intake at all, really. Just tossing an idea in the ring.....