how relevant? in my opinion,and it's just my opinion, there are 2 types of people who off road ,not including racing.the person who asesses the trail,notes the potential hazards,picks a safe line or likely bypass and proceeds in a reasonable manner in the appropriate gear,be it water,mud sand.then there's the one who says"hold my beer and watch this".which one is likely to have the snorkel?
The Snorkel's relevance to North American overlanding
- Thread starter Dalko43
- Start date
Stryder106
Explorer
No - this is normal stuff. If you are not moving fast in silt - well you won't be moving at all. As for that river crossing - that's me and my truck. Anyone who wants to do Mojave Road has to cross this river unless bailing out way early. And yes, proper speed to create a bow wave, but do you notice the water level at rear portion of my front fender well? That's where my stock air intake was located (albeit on the passenger side). Wash crossings are normal and I do assess risk before I do anything. The snorkel is cheap insurance that adds more capability over the stock intake opening.
Stryder106
Explorer
Most likely the guy who knows how to assess risk and capability along with how to make his own equipment more capable and less prone to ingesting water or dirt. The "hold my beer" types end up flagging the rest of us down for assistance with their broke or stuck vehicle.
GoinBoardin
Observer
I've done some river crossings like the one you pictured in my old F150 in the Rockies. The intake is at hood line. It was nerve wracking. I do not have a snorkel but can see the merit in one. More than once water has been deeper than I thought, both from not checking (when I was younger), and from missing the deep spot when I did check.
To touch on something I saw mentioned earlier: Driving around water hazards is not something I consider acceptable. It widens trails, a common complaint against motorized users. Such off trail travel can get areas shut down. If there is an obstacle in front of me I investigate & run it or turn back because of capability limitations. Unfortunately a few others do not share this practice, and the local FS office has had to spend time & money to block all the bypasses, all while pressure mounts against open access to public lands for motorized travel.
My opinion: If you need the snorkel to run the trail or want the added protection, get the snorkel. If it looks cool while going to the mall, I couldn't care less what you do.
southpier
Expedition Leader
and yet, I register my van at the Department of Motor Vehicles. there are no motors allowed on the bike path, but the old farts on their electric assist bikes fly up and down. go figure, huh...
I'm not a Baja-guy. If that type of driving is normal for you, a snorkel might make sense. I don't think that sort of driving is normal for most of the snorkel-armed rigs I see driving around in my area.
When I referred to bypasses earlier in the thread, I was referring to maintained and legal roads that went around the water obstacles. Obviously I don't condone creating informal and illegal bypasses for water obstacles. Also, constant traffic going through water obstacles create their own set of environmental problems over time. In fact, many so-called "water obstacles" exist because of trail erosion that has been caused by vehicular traffic.
I think over the long term, US Forest Service and other State and Federal agencies will be clamping down on water crossings and trail erosion, either with gates or better road construction. The road infrastructure is only going to grow in North America as time goes on and I predict there will be less areas where snorkels are truly a necessity.
dwh
Tail-End Charlie
And no mention of the venturi effect or scavenging...
True, the engine is an air pump - it sucks air. Through a hole. As the air is sucked through the hole, the air stretches and becomes less dense. That's the venturi effect. Ramming air helps to compensate for that.
If you've got a 650 cfm carb or throttle body, ram air won't make more than 650 cfm flow through the hole. BUT it can make 650 cubic feet of DENSER AIR flow through the hole.
But that only gets you so far. To make the most of that, you also have to make sure each intake stroke gets the maximum fuel-air charge. To do that, you have to make sure that all of the burned gasses from the last stroke exit the cylinder. Simply counting on the piston to push all the exhaust out isn't enough...the piston is trying to push air out - through a hole. The burned gasses end up getting compressed on the way out and not everything gets evacuated, so the cylinder still has a bit of burned gas in it when the intake valve opens - leaving less room for a full charge of fresh fuel-air mixture.
Putting on a bigger exhaust pipe (headers) helps, but not enough. The exhaust has to be designed to create a vacuum at the right exhaust port at the right moment, so that when the exhaust valve opens, the burned gasses get SUCKED OUT. That's scavenging.
Ramming air to increase density to mitigate the venturi effect won't do much unless it's combined with proper scavenging.
But ramming air does make a difference.
And this is all basic "Hot Rodding 101" - the "experts" should already know this stuff.
True, the engine is an air pump - it sucks air. Through a hole. As the air is sucked through the hole, the air stretches and becomes less dense. That's the venturi effect. Ramming air helps to compensate for that.
If you've got a 650 cfm carb or throttle body, ram air won't make more than 650 cfm flow through the hole. BUT it can make 650 cubic feet of DENSER AIR flow through the hole.
But that only gets you so far. To make the most of that, you also have to make sure each intake stroke gets the maximum fuel-air charge. To do that, you have to make sure that all of the burned gasses from the last stroke exit the cylinder. Simply counting on the piston to push all the exhaust out isn't enough...the piston is trying to push air out - through a hole. The burned gasses end up getting compressed on the way out and not everything gets evacuated, so the cylinder still has a bit of burned gas in it when the intake valve opens - leaving less room for a full charge of fresh fuel-air mixture.
Putting on a bigger exhaust pipe (headers) helps, but not enough. The exhaust has to be designed to create a vacuum at the right exhaust port at the right moment, so that when the exhaust valve opens, the burned gasses get SUCKED OUT. That's scavenging.
Ramming air to increase density to mitigate the venturi effect won't do much unless it's combined with proper scavenging.
But ramming air does make a difference.
And this is all basic "Hot Rodding 101" - the "experts" should already know this stuff.
Last edited:
MOguy
Explorer
Why not get involved in another part of this conversation. DUST. Many of you talk about the Mojave. I spent years living in it while stationed at Fort Irwin. I spent 10+ days a month for about 3 years LIVING out of a H1 running around playing the enemy (OPFOR). I spent many many many many many many more days (most of them) just driving through the desert in my Jeep and in Army H1s. I have lived in dust. I have been out in dust storms, I have driven in dust so thick you can't see the front of your hood. I have done this over and over and over. Even high up on taller vehicles or trailers (higher than a snorkel) there would be thick dust. Outside my H1 was far more dusty then in the engine compartment. Based on my experience I would chose an intake in the engine compartment before a snorkel.
We didn't use snorkels we used the item I have pictured below. I am not saying the Snorkel might not possible help for dust (I am just trying to insinuate it) with dust put I don't think they are the best solution. I still think they could be the best bet for water, I am not sure either way about more air, but I would think they could bring in cooler air. I don't live in a place in more where dust is any issue like it was in the Mojave anymore. It I did and I was looking for a solution to reduce the dust intake and water issue I would look for a snorkel with one of these "pre filters" on it.
We didn't use snorkels we used the item I have pictured below. I am not saying the Snorkel might not possible help for dust (I am just trying to insinuate it) with dust put I don't think they are the best solution. I still think they could be the best bet for water, I am not sure either way about more air, but I would think they could bring in cooler air. I don't live in a place in more where dust is any issue like it was in the Mojave anymore. It I did and I was looking for a solution to reduce the dust intake and water issue I would look for a snorkel with one of these "pre filters" on it.
Last edited:
dwh
Tail-End Charlie
Snorkels can increase the venturi effect, lowering the density of the air getting sucked into the engine.
But if the snorkel helps keeps water and other crap out of the engine, what the hell...WHY NOT do it?
Airing down tires reduces performance as well, but if it helps keep the vehicle from getting stuck...WHY NOT do it?
Arguing that "I never needed a snorkel" is like arguing that "I never needed to air down my tires". That only means you got lucky. Arguing that everyone should depend on luck rather than being proactive is a damned weak argument.
But if the snorkel helps keeps water and other crap out of the engine, what the hell...WHY NOT do it?
Airing down tires reduces performance as well, but if it helps keep the vehicle from getting stuck...WHY NOT do it?
Arguing that "I never needed a snorkel" is like arguing that "I never needed to air down my tires". That only means you got lucky. Arguing that everyone should depend on luck rather than being proactive is a damned weak argument.
MOguy
Explorer
I hope you are joking. They pre filter traps larger particles so you have to clean your filter less but cleaning an oil soaked sponges sucks. It saves you no time and very little money, if any at all. They become very restrictive muddy oil soaked sponges. Oil type (K&N type items) are far more trouble then they are worth.
If you want a prefiter use the centrifuge type.
Last edited:
Enjoying the conversation here, I do like snorkels but i don't have use for it despite the occasional dust trail ride. I have more problem keeping the dust out of my Jeep interior when running a soft top.
fwiw, unless there are dynoed results of these snorkels helping performance, it is hard to imagine it increasing performance and if not actually reducing it (negligible in context of 4WD). Comparing these to performance vehicles, imho, is not even close. Those intakes are highly engineered to provide the shortest path and highest volumetric efficiency. Those stock intakes are even tuned to typically help on improving torque for daily driving, whereas the extreme of putting velocity stacks will improve peak HP but will likely kill low-end torque. Imagine the snorkel with its long tube and twists (and some designs even involve a lot of twisting), you would imagine that is not helping the airflow at all. If anything i see the cold-air advantage although most stock intakes are well-designed to not pull engine bay air. However, i am speculating by just how these snorkel looks, that it is not helping the overall efficiency at all. Having said that, 4LO, who cares about a loss of 5hp at peak RPM when you are crossing that creek.
fwiw, unless there are dynoed results of these snorkels helping performance, it is hard to imagine it increasing performance and if not actually reducing it (negligible in context of 4WD). Comparing these to performance vehicles, imho, is not even close. Those intakes are highly engineered to provide the shortest path and highest volumetric efficiency. Those stock intakes are even tuned to typically help on improving torque for daily driving, whereas the extreme of putting velocity stacks will improve peak HP but will likely kill low-end torque. Imagine the snorkel with its long tube and twists (and some designs even involve a lot of twisting), you would imagine that is not helping the airflow at all. If anything i see the cold-air advantage although most stock intakes are well-designed to not pull engine bay air. However, i am speculating by just how these snorkel looks, that it is not helping the overall efficiency at all. Having said that, 4LO, who cares about a loss of 5hp at peak RPM when you are crossing that creek.
dwh
Tail-End Charlie
Neither. It's providing "denser" air.
Last edited:
dwh
Tail-End Charlie
That's not an "oil bath" air filter. That's an "oil wetted" air filter. Different sort of beast.
