pod filter on zuk???
pod filter on zuk???
some people i no have got a pod filter that they put on their air intake when they are on the road, and conect their snorkel when they go off road, apperantly its better on fuel consumption. will it have any effect if i put one on my zuk?????????
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mroffroader
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Im not sure about switching them from snorkel to pod...but with a pod you will get better performance as the air can flow more freeley thus mixing more fuel and giving a bigger bang and you away... :fart: im not sure about fuel consumption...I thought it would be worse...?
80 series tow bus towing a redneck ass vitara 
alot of people take the air box out of cars and put a pod on cos they have been told they will get more power ect. but the gain for the extra flow is lost because of increased heat of the air going in. the air box normanly has a good feed of cold air. if you put a pod on look at making some sort of shielding and a cold air duct.
pete
pete
Someone will be able to tell you in more detail and correct terminology but there is also the whole ?forced induction> principle of the air gets rammed down a snorkle and forced into the engine and therefore increases amount of 02 and burning hotter or something along those lines...
and as pete said its a lot of work to fit a pod as you have to make all the shielding etc...
Here's an article i read a while back...
SORRY FOR THE LONG POST
and as pete said its a lot of work to fit a pod as you have to make all the shielding etc...
Here's an article i read a while back...
SORRY FOR THE LONG POST
Last edited by icekayak on Mon Sep 18, 2006 8:12 pm, edited 1 time in total.
There are two critical aspects to a modified air intake system - the volume of airflow and the temperature of the intake air. Combine these two factors and we know the mass of intake airflow; it's this weight of air being inhaled by the engine that's the most important factor in determining the power that can be developed.
Our aim - from a maximum power point of view - is to maximise intake airflow (by reducing restriction) and to maintain the lowest possible intake temperature.
How It Works...
Increasing intake airflow and reducing intake temperatures achieve a similar end result - greater combustion pressure and, therefore, torque.
By enhancing intake airflow, you allow each descending piston to inhale a larger mass of air into its combustion chamber. The greater the mass of inhaled air, the more fuel that can be mixed with it. And the more air and fuel that you get to burn, the greater the combustion pressure.
Lowering intake air temperature - without changing the intake flow volume - also results in a greater charge-air mass. This is due to cooler air being denser and, therefore, heavier.
In addition to increasing combustion pressure, maintaining a cool intake air supply serves to reduce the chance of detonation. Detonation is an unstable and rapidly spiking combustion process that can cause major engine damage; anything that suppresses detonation is very welcome.
Other Factors
Many modern cars use a complex engine management system, which can affect the end result of intake modifications.
If - for example - intake air temperature is increased, the ECU may load an excessive amount of fuel into the combustion chamber. This results in a significant reduction of torque.
Furthermore, if intake temperature goes up substantially, those vehicles equipped with a knock sensor will retard their ignition timing in large steps. This results in a further reduction of torque.
Different Approaches to Modification...
On factory intake systems, the path to the air filter is usually quite restrictive; in our experience, it's typically 25 percent of the total restriction before the throttle body (or turbo on those engines).
So what can we do about it?
There are two common solutions:
Install an aftermarket pod air filter, replacing the entire airbox and snorkel assembly
Revise the existing pre-filter hardware
Let's take a look at the pros and cons of each approach...
Installing a Pod Filter With No Other Mods
Discarding the factory airbox, filter and snorkel and installing an aftermarket pod filter is a guaranteed way to massively improve intake airflow. The only remaining restriction (at this part of the system) is the filter element itself - and that's usually negligible.
There are some major downsides, however.
Without any other mods, an aftermarket pod filter will be inhaling intense under-bonnet heat. Don't breeze over this fact because, quite often, the increased intake air temperature completely undoes the benefits the freer flowing intake might otherwise give. At the same time, the likelihood of detonation is also increased.
Other potential problems are:
Cost (a brand name filter can often cost a couple of hundred dollars)
A rougher idle (the flow through the airflow meter can get disrupted)
Airflow meter damage (the oil from the filter can be deposited on the hot wire)
Noise (induction roar can be excessive)
Effectiveness of cleaning (a washable air filter is often viewed as a plus, but getting it to maintain its filtration and flow performance after it's been cleaned is problematical, in fact look below...)
Unknown filtration quality
We should point out the abovementioned filtering problem can be major. You can be certain car manufacturers extensively test the dust filtration effectiveness of their standard air filter; who knows how effective the filtration of an aftermarket product is? The chances are that if it flows better, it lets bigger particles through to the engine. For this reason, it's dangerous to pay attention to 'filter tests' that have been performed solely on a dyno - the filter that makes the best power is unlikely to be the best filter overall.
Don't be completely put off, though - pod filter installations can be quite effective when installed intelligently. We'll cover this in detail in Part 2...
Revising the Existing Path Into the Airbox
Pre-filter restriction in a standard intake system is invariably caused by there being too many bends and insufficient duct cross-section. Some cars also have their pick-ups placed up close to panelwork (which hinders flow into the intake mouth), while others suck the intake air through resonant boxes (these can be simply tee'd into the intake duct, or integrated as part of the system so all of the intake air has to pass through - that latter is worse).
With so many causes of restriction, you have to be ruthless in your approach to modification.
Depending on the specific mods you perform, a revised path into the airbox can give terrific gains - even more terrific when you take into account the cost. By enlarging the feedhole into your airbox and running a large forward-facing duct to it (which, again, we'll come to in Part 2) you can eliminate nearly all of the restriction prior to the filter.
In comparison, an aftermarket pod filter will out-flow a revised intake feed - that's because there'll still be a tiny pressure drop across the revised intake (though probably immeasurable), and there's the restriction of the standard filter element and the flow through the airbox. In any case, doing a good job revising the airbox feed should remove half to three-quarters of the restriction previously seen in that area.
While the revised path to the filter doesn't flow quite as well as a pod filter, there are numerous advantages that sway favour back towards it:
Revising the path into the filter is cheap
Idle quality won't be affected - or certainly nowhere near as much
There's no inherent possibility of damage to airflow meters
Maintains a high level of dust filtration
The engine inhales much cooler air (depending on where you site the pick-up)
Induction roar is minimised
Near factory under-bonnet appearance - or is that a bad thing?
Obviously, this approach to modification has relatively few problems - we'll cover 'how to' in the next instalment.
Oh, you might also be contemplating dropping an aftermarket filter insert into your airbox. Chances are you won't gain a thing; based on our previous intake testing, the standard filter element in an un-touched intake system is responsible for only around 3 percent of the total restriction. A drop-in replacement won't make any noticeable difference.
Again, though, the 'advantage' of a washable aftermarket filter might be attractive to you - it depends on the cost of new OE filter replacements versus the initial cost of the aftermarket filter and any necessary washing chemicals. Keep in mind filtration performance as well.
Replacing the Airbox
If the size, shape and inlet/outlet diameters of your airbox are causing excessive restriction, it's possible to replace it with a freer-flowing unit out of another car.
Without flow-bench testing, it's difficult to guess whether a given airbox offers less restriction than the one you've already got. As a rule, though, the larger the filter area and the smoother the box contours are, the better. Other factors to look for include a bellmouth'd exit (or the whole box shaped to flow into the exit), and really big diameter entrance and exit pipes.
After you've picked out the airbox of your (car's) dreams, make sure you check the price of new OE replacement filters - it's no good picking an airbox if you have to pay an arm and leg for the filter inserts. Go for a common airbox to ensure you can get cheap replacement filters.
The biggest hassle with the new airbox approach is it's often difficult to find a box that fits in the engine bay cavity and has intake and outlet pipes in the right places; a lot of searching is likely to be required. Where possible, one trick is to look for boxes from a later model of the same car: sometimes the manufacturer have made up-dates and come up with an improved design - one that will fit into place in the older engine bay.
In short, upgrading your airbox is a neat way of doing things - but, unfortunately, it's a case-by-case scenario.
Now you know the pros and cons of the two common approaches to intake mods. In Part 2 of Into the Intake we'll give you the how-to details of installing an aftermarket pod filter and revising the intake to the airbox...
Our aim - from a maximum power point of view - is to maximise intake airflow (by reducing restriction) and to maintain the lowest possible intake temperature.
How It Works...
Increasing intake airflow and reducing intake temperatures achieve a similar end result - greater combustion pressure and, therefore, torque.
By enhancing intake airflow, you allow each descending piston to inhale a larger mass of air into its combustion chamber. The greater the mass of inhaled air, the more fuel that can be mixed with it. And the more air and fuel that you get to burn, the greater the combustion pressure.
Lowering intake air temperature - without changing the intake flow volume - also results in a greater charge-air mass. This is due to cooler air being denser and, therefore, heavier.
In addition to increasing combustion pressure, maintaining a cool intake air supply serves to reduce the chance of detonation. Detonation is an unstable and rapidly spiking combustion process that can cause major engine damage; anything that suppresses detonation is very welcome.
Other Factors
Many modern cars use a complex engine management system, which can affect the end result of intake modifications.
If - for example - intake air temperature is increased, the ECU may load an excessive amount of fuel into the combustion chamber. This results in a significant reduction of torque.
Furthermore, if intake temperature goes up substantially, those vehicles equipped with a knock sensor will retard their ignition timing in large steps. This results in a further reduction of torque.
Different Approaches to Modification...
On factory intake systems, the path to the air filter is usually quite restrictive; in our experience, it's typically 25 percent of the total restriction before the throttle body (or turbo on those engines).
So what can we do about it?
There are two common solutions:
Install an aftermarket pod air filter, replacing the entire airbox and snorkel assembly
Revise the existing pre-filter hardware
Let's take a look at the pros and cons of each approach...
Installing a Pod Filter With No Other Mods
Discarding the factory airbox, filter and snorkel and installing an aftermarket pod filter is a guaranteed way to massively improve intake airflow. The only remaining restriction (at this part of the system) is the filter element itself - and that's usually negligible.
There are some major downsides, however.
Without any other mods, an aftermarket pod filter will be inhaling intense under-bonnet heat. Don't breeze over this fact because, quite often, the increased intake air temperature completely undoes the benefits the freer flowing intake might otherwise give. At the same time, the likelihood of detonation is also increased.
Other potential problems are:
Cost (a brand name filter can often cost a couple of hundred dollars)
A rougher idle (the flow through the airflow meter can get disrupted)
Airflow meter damage (the oil from the filter can be deposited on the hot wire)
Noise (induction roar can be excessive)
Effectiveness of cleaning (a washable air filter is often viewed as a plus, but getting it to maintain its filtration and flow performance after it's been cleaned is problematical, in fact look below...)
Unknown filtration quality
We should point out the abovementioned filtering problem can be major. You can be certain car manufacturers extensively test the dust filtration effectiveness of their standard air filter; who knows how effective the filtration of an aftermarket product is? The chances are that if it flows better, it lets bigger particles through to the engine. For this reason, it's dangerous to pay attention to 'filter tests' that have been performed solely on a dyno - the filter that makes the best power is unlikely to be the best filter overall.
Don't be completely put off, though - pod filter installations can be quite effective when installed intelligently. We'll cover this in detail in Part 2...
Revising the Existing Path Into the Airbox
Pre-filter restriction in a standard intake system is invariably caused by there being too many bends and insufficient duct cross-section. Some cars also have their pick-ups placed up close to panelwork (which hinders flow into the intake mouth), while others suck the intake air through resonant boxes (these can be simply tee'd into the intake duct, or integrated as part of the system so all of the intake air has to pass through - that latter is worse).
With so many causes of restriction, you have to be ruthless in your approach to modification.
Depending on the specific mods you perform, a revised path into the airbox can give terrific gains - even more terrific when you take into account the cost. By enlarging the feedhole into your airbox and running a large forward-facing duct to it (which, again, we'll come to in Part 2) you can eliminate nearly all of the restriction prior to the filter.
In comparison, an aftermarket pod filter will out-flow a revised intake feed - that's because there'll still be a tiny pressure drop across the revised intake (though probably immeasurable), and there's the restriction of the standard filter element and the flow through the airbox. In any case, doing a good job revising the airbox feed should remove half to three-quarters of the restriction previously seen in that area.
While the revised path to the filter doesn't flow quite as well as a pod filter, there are numerous advantages that sway favour back towards it:
Revising the path into the filter is cheap
Idle quality won't be affected - or certainly nowhere near as much
There's no inherent possibility of damage to airflow meters
Maintains a high level of dust filtration
The engine inhales much cooler air (depending on where you site the pick-up)
Induction roar is minimised
Near factory under-bonnet appearance - or is that a bad thing?
Obviously, this approach to modification has relatively few problems - we'll cover 'how to' in the next instalment.
Oh, you might also be contemplating dropping an aftermarket filter insert into your airbox. Chances are you won't gain a thing; based on our previous intake testing, the standard filter element in an un-touched intake system is responsible for only around 3 percent of the total restriction. A drop-in replacement won't make any noticeable difference.
Again, though, the 'advantage' of a washable aftermarket filter might be attractive to you - it depends on the cost of new OE filter replacements versus the initial cost of the aftermarket filter and any necessary washing chemicals. Keep in mind filtration performance as well.
Replacing the Airbox
If the size, shape and inlet/outlet diameters of your airbox are causing excessive restriction, it's possible to replace it with a freer-flowing unit out of another car.
Without flow-bench testing, it's difficult to guess whether a given airbox offers less restriction than the one you've already got. As a rule, though, the larger the filter area and the smoother the box contours are, the better. Other factors to look for include a bellmouth'd exit (or the whole box shaped to flow into the exit), and really big diameter entrance and exit pipes.
After you've picked out the airbox of your (car's) dreams, make sure you check the price of new OE replacement filters - it's no good picking an airbox if you have to pay an arm and leg for the filter inserts. Go for a common airbox to ensure you can get cheap replacement filters.
The biggest hassle with the new airbox approach is it's often difficult to find a box that fits in the engine bay cavity and has intake and outlet pipes in the right places; a lot of searching is likely to be required. Where possible, one trick is to look for boxes from a later model of the same car: sometimes the manufacturer have made up-dates and come up with an improved design - one that will fit into place in the older engine bay.
In short, upgrading your airbox is a neat way of doing things - but, unfortunately, it's a case-by-case scenario.
Now you know the pros and cons of the two common approaches to intake mods. In Part 2 of Into the Intake we'll give you the how-to details of installing an aftermarket pod filter and revising the intake to the airbox...
Installation Methods...
How to Pick and Install a Pod Filter
There are a few key factors when selecting an aftermarket pod filter.
From a performance standpoint it's best to buy a filter that has the largest element area - for a given filtering material, the greater the element area, the less airflow restriction. The shape of filter is largely irrelevant - so long as it fits in your engine bay, it's fine. There are whispers about a conical filter aiding flow though the centre of the intake opening, but we're yet to see anything proven.
The particular brand you run with comes down largely to personal preference, but it's a good idea to chat with various people who have used an assortment of filters. We've heard some ghastly tales of inadequate dust filtration when we've spoken to off-road racers, for example. (And we've also seen some of those guys running a quite different filter inside a sponsor's external sock filter!)
Most filters are sold as a universal fitment product - that means you don't get the necessary adaptor to attach it to your intake, nor any filter support structure. The cost of these two easily overlooked items can quickly mount up - by the time you get a metal plate cut out to suit your airflow meter (if you have one), have a length of pipe welded on in addition to a couple of structural support rods and - finally - get it all powder coated, you can be up for $100 - $150. Pre-fabricated adapters can be bought to suit various cars for around $70.
The quick-and-easy bolt-on appeal of an aftermarket pod cops a further beating when you consider what's involved in a 'proper' installation...
Underbonnet heat is the enemy of any exposed under-bonnet air filter - remember, hot intake air can undo the potential benefits of reduced restriction. To get around this you need to fabricate (or get someone else to fabricate) a comprehensive heat shield. When we say 'comprehensive', it has to box the filter off, or - at least - enclose it with a perfect seal against the inner guard and bonnet. There can be nowhere left open for hot air to be drawn through.
A lot of people use sponge rubber or C-section automotive edge trimming (the kind you see being used around door apertures) to make the seal against the bodywork. It's a neat idea.
While sealing the edge of the shield is ultra important, it is equally important that the shield is fabricated from a material that'll keep the under-bonnet heat on the 'other' side. Stainless steel is a traditional favourite here, but - really - the thicker and better insulator the divider is, the better.
A guaranteed way of reducing under-bonnet heat transfer is to make the shield out of blank sheets of 'double layer heat management material' as used on the exhaust manifold of current Ford Falcons. A section 760mm x 412mm can be bought for around $75 from various exhaust component wholesalers. Mount the heat shield to the vehicle body using rivets or bolts and nuts.
A Quick Word on Pod Intakes
Just because you're going to install a cold air duct to the filter, that doesn't get you out of making a heat shield.
When there isn't air being forced through the intake (ie when the car's not travelling at speed), the filter will be inhaling stagnant engine bay heat. And - even when the car is up to speed and there's cool air flowing through the intake duct - what makes you think the filter will selectively suck in the cool air, not the hot air also swirling around with it?
A heat shield is 100 percent mandatory!
Yet another consideration is the proximity of the filter to surrounding body panels - there's not a lot of point squeezing a filter up against the inner guard, because it won't flow to its fullest potential. An open area for the filter works best.
So there are a few essential points to remember:
Buy the filter with the largest element area
Speak to others about their filter's performance - particularly in regard to their experience re dust filtration
An intake adapter is needed, along with supports to hold the filter in position (some pod filters are sold as a complete package, but most aren't)
Underbonnet heat must be avoided at all costs - use an effective heat shield that thoroughly seals the filter area from under-bonnet heat
Mount the filter in 'clean air' under the bonnet - not jammed up against anything
The final - and one of the most important - considerations is running a cold air feed to the filter. Since this applies to any type of intake system, we'll get to this after we've discussed...
How to Pick and Install a Pod Filter
There are a few key factors when selecting an aftermarket pod filter.
From a performance standpoint it's best to buy a filter that has the largest element area - for a given filtering material, the greater the element area, the less airflow restriction. The shape of filter is largely irrelevant - so long as it fits in your engine bay, it's fine. There are whispers about a conical filter aiding flow though the centre of the intake opening, but we're yet to see anything proven.
The particular brand you run with comes down largely to personal preference, but it's a good idea to chat with various people who have used an assortment of filters. We've heard some ghastly tales of inadequate dust filtration when we've spoken to off-road racers, for example. (And we've also seen some of those guys running a quite different filter inside a sponsor's external sock filter!)
Most filters are sold as a universal fitment product - that means you don't get the necessary adaptor to attach it to your intake, nor any filter support structure. The cost of these two easily overlooked items can quickly mount up - by the time you get a metal plate cut out to suit your airflow meter (if you have one), have a length of pipe welded on in addition to a couple of structural support rods and - finally - get it all powder coated, you can be up for $100 - $150. Pre-fabricated adapters can be bought to suit various cars for around $70.
The quick-and-easy bolt-on appeal of an aftermarket pod cops a further beating when you consider what's involved in a 'proper' installation...
Underbonnet heat is the enemy of any exposed under-bonnet air filter - remember, hot intake air can undo the potential benefits of reduced restriction. To get around this you need to fabricate (or get someone else to fabricate) a comprehensive heat shield. When we say 'comprehensive', it has to box the filter off, or - at least - enclose it with a perfect seal against the inner guard and bonnet. There can be nowhere left open for hot air to be drawn through.
A lot of people use sponge rubber or C-section automotive edge trimming (the kind you see being used around door apertures) to make the seal against the bodywork. It's a neat idea.
While sealing the edge of the shield is ultra important, it is equally important that the shield is fabricated from a material that'll keep the under-bonnet heat on the 'other' side. Stainless steel is a traditional favourite here, but - really - the thicker and better insulator the divider is, the better.
A guaranteed way of reducing under-bonnet heat transfer is to make the shield out of blank sheets of 'double layer heat management material' as used on the exhaust manifold of current Ford Falcons. A section 760mm x 412mm can be bought for around $75 from various exhaust component wholesalers. Mount the heat shield to the vehicle body using rivets or bolts and nuts.
A Quick Word on Pod Intakes
Just because you're going to install a cold air duct to the filter, that doesn't get you out of making a heat shield.
When there isn't air being forced through the intake (ie when the car's not travelling at speed), the filter will be inhaling stagnant engine bay heat. And - even when the car is up to speed and there's cool air flowing through the intake duct - what makes you think the filter will selectively suck in the cool air, not the hot air also swirling around with it?
A heat shield is 100 percent mandatory!
Yet another consideration is the proximity of the filter to surrounding body panels - there's not a lot of point squeezing a filter up against the inner guard, because it won't flow to its fullest potential. An open area for the filter works best.
So there are a few essential points to remember:
Buy the filter with the largest element area
Speak to others about their filter's performance - particularly in regard to their experience re dust filtration
An intake adapter is needed, along with supports to hold the filter in position (some pod filters are sold as a complete package, but most aren't)
Underbonnet heat must be avoided at all costs - use an effective heat shield that thoroughly seals the filter area from under-bonnet heat
Mount the filter in 'clean air' under the bonnet - not jammed up against anything
The final - and one of the most important - considerations is running a cold air feed to the filter. Since this applies to any type of intake system, we'll get to this after we've discussed...
If you run the car with no air filter you can't even notice the difference in power so really for all the hassle best to just find something that fits.
As for the snorkel... on a zuk (samurai at least) the kit is so crap and adds so many bends the fuel consumption goes to s*($. Well thats by my first tests. Not to mention makes the battery's hard to fit because the pipe steals so much room.
Short and sweet... Leave it stock. If you want a pod make sure it's in a box with cold air coming in
But that's going to be bad off road when it sends water in instead of air on the first bog. If you want more power get a blower or turbo 
I yet to see any evidence that a snorkel provides positive presure at any resonable speed. And even if it does it'll be so slight you can't notice.
As for the snorkel... on a zuk (samurai at least) the kit is so crap and adds so many bends the fuel consumption goes to s*($. Well thats by my first tests. Not to mention makes the battery's hard to fit because the pipe steals so much room.
Short and sweet... Leave it stock. If you want a pod make sure it's in a box with cold air coming in
But that's going to be bad off road when it sends water in instead of air on the first bog. If you want more power get a blower or turbo
I yet to see any evidence that a snorkel provides positive presure at any resonable speed. And even if it does it'll be so slight you can't notice.
But with a pod it's only about 10L per 100km...
)
I read in an ozzy 4x4 mag a while ago, driving at 120k's produces something like 2 pounds pressure down a 3" snorkle. F#ck all in the scheme of things, just put the palm f your hand out the window next time your on the motorway and you see for your self 
Your better to have the hat facing rearwards so you can hit bogs faster
Your better to have the hat facing rearwards so you can hit bogs faster
lax2wlg wrote:Is that like saying 'she's hot, for a crackwhore??
I'm just a tight arse when it comes to gas. And that was about 3 tanks for each but mainly around town stuff... hmmm and I did have to tow Al's zuk on that last tank.
Is it a problem I got grumpy and ripped the snorkel off at lunch time
I think I'm just going to put a big ball valve in there so I can use snorkel or no snorkel. Plus I need to mod the mounting as I've ripped it off about 3 times. Silicon is good for a while but the time has come to try and do it a bit better.
Every time I spend the money to get something done properly at a 4x4 shop it ends up being crap.
I guess it's a bit of a reflection on the micky mouse industry? Or maybe just I'm visiting the wrong shops.
Is it a problem I got grumpy and ripped the snorkel off at lunch time
I think I'm just going to put a big ball valve in there so I can use snorkel or no snorkel. Plus I need to mod the mounting as I've ripped it off about 3 times. Silicon is good for a while but the time has come to try and do it a bit better.
Every time I spend the money to get something done properly at a 4x4 shop it ends up being crap.
I guess it's a bit of a reflection on the micky mouse industry? Or maybe just I'm visiting the wrong shops.
zuky wrote:I'm just a tight arse when it comes to gas. And that was about 3 tanks for each but mainly around town stuff... hmmm and I did have to tow Al's zuk on that last tank.
Is it a problem I got grumpy and ripped the snorkel off at lunch time
I think I'm just going to put a big ball valve in there so I can use snorkel or no snorkel. Plus I need to mod the mounting as I've ripped it off about 3 times. Silicon is good for a while but the time has come to try and do it a bit better.
Every time I spend the money to get something done properly at a 4x4 shop it ends up being crap.
I guess it's a bit of a reflection on the micky mouse industry? Or maybe just I'm visiting the wrong shops.
Is this the same person who was discussing his wifes disgust at your monthly "entertainment" bill the other night??
DieselBoy wrote:I read in an ozzy 4x4 mag a while ago, driving at 120k's produces something like 2 pounds pressure down a 3" snorkle.
Hmmm something dodgy going on with their calculations there... 2PSI would be quite noticable!
Static pressure is
P = 1/2 rho * v^2
Where rho is the density of air (1.2kg/m^3) and v is velocity in meters/second. 120 kmh = about 33 m/s
So
P = 1/2 * 1.2 * 33^2
P = 667 Pascals
1 Pascal = 145.04×10^-6 PSI
667 Pascals = 0.097 PSI...
In other words... bullshit. You need to go nearly 400km/h to get 1 PSI.
Ben
Last edited by Ben on Wed Sep 20, 2006 8:37 pm, edited 1 time in total.
-
mroffroader
- Hard Yaka
- Posts: 2330
- Joined: Sat Mar 25, 2006 12:00 pm
- Location: Lower Hutt WELLINGTON :D
- Contact:
Ben wrote:DieselBoy wrote:I read in an ozzy 4x4 mag a while ago, driving at 120k's produces something like 2 pounds pressure down a 3" snorkle.
Hmmm something dodgy going on with their calculations there... 2PSI would be quite noticable!
Static pressure is
P = 1/2 rho * v^2
Where rho is the density of air (1.2kg/m^3) and v is velocity in meters/second. 120 kmh = about 33 m/s
So
P = 1/2 * 1.2 * 33^2
P = 667 Pascals
1 Pascal = 145.04×10^-6 PSI
667 Pascals = 0.097 PSI...
In other words... bullshit. You need to go nearly 400km/h to get 1 PSI.
Ben
Hehe, sweeeeeet, no argueing with that, very kool
!!!!
My point still stands, it doesn't generate any amount of noteworthy pressure
lax2wlg wrote:Is that like saying 'she's hot, for a crackwhore??