Outer Limits 4x4 Board

Ok so a little debate here! which is better and why?

I'm running Air to Air because IMHO...

It's in front
It gets the clean air and doesn't get heat soak.
No moving parts
No pump
No Rad to repair etc...
Once you come off the pedal, the EGT's come down way quick - even when doing long hills.
Very efficient when towing etc to keep EGT below 550...
Only bitch is 40+ degree days - mind you who's wheelin in that?

Air to Air - if you can fit it. Transfer is Air - Alloy - Air

Water to Air has to transfer the heat from Air - Alloy - Water - Alloy - Air
There is an efficiecny loss at each one.

People talk about the amount of heat water can hold - great, just what a want - a heap of hot water re-heating my air. I don't want the water to hold heat, I want the outside airstream to take it away.

In a petrol that is on boost for 10% of the time, the water is a great spot to dump heat really quicly for short boost events.

In a diesel that may be on boost for 80% of the time, it's just a conveyor taking it away, no one cares how much the convenyor holds, just how fast it moves it.

The MAIN thing is how big is the FRONT cooler for the water to Air. If it can't dump the heat, the water will just get hotter. Most are way too small. suppsodly cause water is more efficient. Remember, it's the outside aire that takes the heat away, not the water.

Water to air is more complex, expensive, holds heat too much, and if it leaks may kill your diesel.

The advantage may be that the plumbing is easier to route than large air pipes, for short term boost events a smaller system can deal well, and the shorter air runs may give improved transient boost response.

I would consider one, but it's not superior.

Paul

Short Answer:
Bang for buck air to air wins hands down.

Long Answer:
Water to air if you can afford to do it correctly, but its far more expensive than its worth.

A few kits can be found here - http://www.pwr.com.au/coolers_ltoa.html

The biggest problem is the danger (however remote that may be) that a stone/stick/whatever punctures the inlet heat exchanger and your engine drinks some water, enough water can cause a hydraulic lock which as you would expect will bend some rods.

Kiint wrote:Short Answer:
Bang for buck air to air wins hands down.

Long Answer:
Water to air if you can afford to do it correctly, but its far more expensive than its worth.

A few kits can be found here - http://www.pwr.com.au/coolers_ltoa.html

The biggest problem is the danger (however remote that may be) that a stone/stick/whatever punctures the inlet heat exchanger and your engine drinks some water, enough water can cause a hydraulic lock which as you would expect will bend some rods.

Kiint where are you suggesting a stick etc will damage the heat exchanger. The only way water can escape and get into your inlet tract is if the core cracks or the welds around the end tanks crack, assuming the water jacket extends over that join a little. You would have to puncture through the water jacket skin then into the core itself for water to enter that way.

Ok so both ways have there advantages and disadvantages! so if i went a air to air which is better top mount or front mount? going in a 75series! Also which manufactures of these kits would you recommand?

Using an air to air cooler, you'll never cool your intake charge below ambient. You really won't get close to ambient actually.

Water to air you will.

fester2au wrote:Kiint where are you suggesting a stick etc will damage the heat exchanger.

As I said, however remote the chances, they are still there. But basically you take a barrel intercooler for instance, all it takes is a stick/rock/whatever to puncture the shell of the intercooler and bend a few of the cores that let air pass through and you have big problems. Its more likely that a weld will give way ... but still I am very uncomfortable having water so close to my air inlet, its one thing for big stakes drag races, its something else to be out bush a thousand miles from anywhere and a problem to arise.

At least with air to air intercoolers even if the intercooler itself is damaged the air inlet danger only comes from particles, which wile damaging, arent as catastrophic as the engine taking a drink of water.

gabe wrote:Using an air to air cooler, you'll never cool your intake charge below ambient. You really won't get close to ambient actually.

Water to air you will.

SAY WHAT!!!!

On planet does the physics of a heat exchanger allow cooling below ambient?

Or are you confused with a water spray using evaporative cooling voer the outside of ANY cooler.

Or are you adding ice to your water every 400m like th drag boys do? Not so good for touring, and the ice might slosh out of the bucket whislt crawling. I need my ice for my beer.

Man I gotta know what you are tripping on.

Paul

Barno111 wrote:Ok so both ways have there advantages and disadvantages! so if i went a air to air which is better top mount or front mount? going in a 75series! Also which manufactures of these kits would you recommand?

Top mount is "better" as the pipe runs are shorter. BUT (Huge BUT) -

a) You generally can't fit a large cooler up there, whereas there is generally more space at the front.

b) All intercoolers depend on outside airflow, that's where the heat gets dumped to, the intercooler is just a means to an end. Top mounts have BIG problems getting adequate airflow, especially at low speeds. If you can get fans to induce airflow, they are good. It also means you aren't compromising your normal cooling system. Most designs don't get enough airflow to top mounts, especially at low speed. You need a fan at low speed. Also the top of the engine bay is where the hto air pools, so your ariflow system has to overcome that issue - again - good fans.

Paul

Go the top mount, There should be plenty of room to one side of the engine bay to fit it in without it having to sit on top of the engine, if possible keep it on the inlet side of the engine bay to minimise heat soak from the hot exhaust.

Kiint wrote:

fester2au wrote:Kiint where are you suggesting a stick etc will damage the heat exchanger.

As I said, however remote the chances, they are still there. But basically you take a barrel intercooler for instance, all it takes is a stick/rock/whatever to puncture the shell of the intercooler and bend a few of the cores that let air pass through and you have big problems. Its more likely that a weld will give way ... but still I am very uncomfortable having water so close to my air inlet, its one thing for big stakes drag races, its something else to be out bush a thousand miles from anywhere and a problem to arise.

At least with air to air intercoolers even if the intercooler itself is damaged the air inlet danger only comes from particles, which wile damaging, arent as catastrophic as the engine taking a drink of water.

As opposed to staking a front mount intercooler whilst in a creek crossing?
I would think theres a much better chance of that happening than a stick puncturing a water/air intercooler.

Most water/air intercoolers are located high in the engine bay, often as a crossover pipe. Not many sticks make it that far.

Shadow wrote:As opposed to staking a front mount intercooler whilst in a creek crossing?
I would think theres a much better chance of that happening than a stick puncturing a water/air intercooler.

Most water/air intercoolers are located high in the engine bay, often as a crossover pipe. Not many sticks make it that far.

Quite true.

I love water to air intercoolers (I had one on my WRX - from the website I posted earlier) and it was far better than the factory intercooler, however it was still a road car obviously.

All I am saying is that it's my opinion that a water intercooler isnt very practical or safe in a 4x4 environment.

I know what you are saying kiint and I realised what you meant but really when you consider almost all water to air core on a 4WD are mounted between the turbo and inlet and therfore sit on the rocker cover mostly around the centre or towards the rear I doubt you could ever stake one with a stick or something. You would have already trashed your grill, radiator, and most likely your fan and belts as well before the stick had any chance of getting near the core. I agree poor construction could be a problem but the chance of physical damage is about as likely as Pauline Hansen ever being taken seriously.

A side question to this for me is say you do get a hairline crack in the construction that would allow water to mix with the air. Likely it would only be a hairline crack or the manufacturer is very slack. So this water would be joining the inlet in pretty small amounts and would it also be vapouring maybe and therefore would it actually be enough on any one compression stroke to actually cause damage. Sorry but I know diesels don't like water but really how much before it causes damage. Obviously a water crossing would generally cause a fair amount to be ingested all at once but a very small leak would it be akin to water injection. I am curious to this as I recently saw stats on a TD42T build up that used glycol injection into the pre-combustion chambers.

fester2au wrote: I recently saw stats on a TD42T build up that used glycol injection into the pre-combustion chambers.

Isnt that just called a cracked head/gasket

Could be but this thing made a shit load of power. Plently of performance tuning on it, was listed on ebay and built by name brand diesel tuning shop down south. The glycol had me beat though, given it is a fluid similar to water I thought it may cause problems but ?I'm not sure what glycol does in that situation and that had me thinking about small quantities of water and hence my line of questioning in ragard to the real world issue of a leaking water to air cooler.

Generally water injection is used in combination with nitrous to prevent detonation. Extended use of nitrous will overheat an engine quickly, and the water injection assists in preventing detonation (preignition) in petrol engines.

I have never heard of glycol injection before, however combining water with methanol and injecting that with the nitrous is a match made in heaven.

Obviously nitrous is very compatible with diesel engines, and a water injection into the preignition chamber would certainly go a long way in preventing the engine from overheating.

im not 100% but im pritty sure when glycol burns its not good...

b4 anyone thinks this is a good idea read this

http://www.oilanalysis.com/article_deta ... icleid=193

me3@neuralfibre.com wrote: SAY WHAT!!!!

On planet does the physics of a heat exchanger allow cooling below ambient?

Or are you confused with a water spray using evaporative cooling voer the outside of ANY cooler.

Or are you adding ice to your water every 400m like th drag boys do? Not so good for touring, and the ice might slosh out of the bucket whislt crawling. I need my ice for my beer.

Man I gotta know what you are tripping on.

Paul

I'm just saying that if you put a front mounted intercooler on your vehicle, the intake charge passing through the cooler will never be cooler than the air passing through it.

Water to Air, whilst more difficult to setup, lets you cool the 'water' before it passes through the cooler, giving you the flexability to achieve much lower inteke temps. If that's your thing.

That's all i'm saying.
Anyway....

Maybe a well setup water injection kit will achieve the results you want. Have you considered this as an option?

gabe wrote:

me3@neuralfibre.com wrote: SAY WHAT!!!!

On planet does the physics of a heat exchanger allow cooling below ambient?

Or are you confused with a water spray using evaporative cooling voer the outside of ANY cooler.

Or are you adding ice to your water every 400m like th drag boys do? Not so good for touring, and the ice might slosh out of the bucket whislt crawling. I need my ice for my beer.

Man I gotta know what you are tripping on.

Paul

I'm just saying that if you put a front mounted intercooler on your vehicle, the intake charge passing through the cooler will never be cooler than the air passing through it.

Water to Air, whilst more difficult to setup, lets you cool the 'water' before it passes through the cooler, giving you the flexability to achieve much lower inteke temps. If that's your thing.

That's all i'm saying.
Anyway....

Maybe a well setup water injection kit will achieve the results you want. Have you considered this as an option?

and what cools the water genius?

The air flowing through the radiator, just like the air/air intercooler.

A water/air intercooler has an extre step of heat transfer, which makes it less efficient.

ultimately there isn't enough time for the air running thru the cooler to reach anywhere near ambient temps, its only to cool it to a more desirable temp

if the internals of a air to water cooler are damaged, i wouldn't the boost pressure push air into the cooling system? effectively stopping or slowing the leak

i know that wont help when not on boost, but as it was said diesels run boost 80% of the time

the issue with air to water coolers is that they work fantastically in short bursts, but once the water heats up too much they have alot of trouble keeping up, when the water heats up too much you end up heating the air or only running a cooler thats an equivalent size to the radiator on the front

there a way too many variables in it tho, like the flow rates of the water pump and size of the radiator for it

a good thing about water to air's is there is normally a fan on the rad whick helps at low speeds and crawling

Shadow wrote:and what cools the water genius?

The air flowing through the radiator, just like the air/air intercooler.

A water/air intercooler has an extre step of heat transfer, which makes it less efficient.

Shadow, you obviously haven't seen many well setup water to air setups. Air is NOT the only way of cooling. Which is what I am trying to say. Google the subject, THEN mouth off.

A well setup water to air system will out-cool ANY well setup air to air setup. Anyone who argues otherwise is in dreamland.

gabe wrote:

Shadow wrote:and what cools the water genius?

The air flowing through the radiator, just like the air/air intercooler.

A water/air intercooler has an extre step of heat transfer, which makes it less efficient.

Shadow, you obviously haven't seen many well setup water to air setups. Air is NOT the only way of cooling. Which is what I am trying to say. Google the subject, THEN mouth off.

A well setup water to air system will out-cool ANY well setup water to air setup. Anyone who argues otherwise is in dreamland.

how do you cool the water?????????????????????????????????????????????? Hiclone?

How about you research anything to do with physics or heat transfer, then come back and apologise for posting utter crap.

Shadow wrote:how do you cool the water?????????????????????????????????????????????? Hiclone?

Glycol. Dry ice. Even ice from your freezer. Just to name a few, and there are plenty of ways I assure you.

I've personally seen sub zero intake temps and INTAKES FREEZING UP on dyno runs, using W2A intercooling. As people have already said, it's THE way to reduce intake temps from an intercooling point of view.

Shadow wrote: How about you research anything to do with physics or heat transfer, then come back and apologise for posting utter crap.

You're a dick. Is it school holidays already....?
You're the one who needs to do some reading. Let me help you. Start by googling the specific heat capacity of water vs air. Then google why it's so important to 'heat transfer'.

And before anyone replys about how rediculous it is to put a complex W2A setup on a 4WD, I agree. But the original post asked for discussion on the pros and cons of each.

Cheers

gabe wrote: Glycol. Dry ice. Even ice from your freezer. Just to name a few, and there are plenty of ways I assure you.

I've personally seen sub zero intake temps and INTAKES FREEZING UP on dyno runs, using W2A intercooling. As people have already said, it's THE way to reduce intake temps from an intercooling point of view.

Ice is used on dyno queens and 1/4 mile runs. And not once did you mention it before now, when your trying to justify your bullshit.

What has glycol got to do with anything, its just an alternative to water, a medium for the transfer of heat.

gabe wrote:
You're a dick. Is it school holidays already....?
You're the one who needs to do some reading. Let me help you. Start by googling the specific heat capacity of water vs air. Then google why it's so important to 'heat transfer'.

And before anyone replys about how rediculous it is to put a complex W2A setup on a 4WD, I agree. But the original post asked for discussion on the pros and cons of each.

Cheers

Im pretty sure when I studied physics at uni I covered specific heat capacity, entropy and enthalpy, so I dont think I need to read up on these topics to know that it has absolutely nothing to do with the prolonged use of a heat transfer system.

The much higher specific heat capacity of water will allow the system to deal with brief periods of increased heat input. ie, dyno queens.

If on the other hand, your engine is a diesel and spends the majority of its time on boost, then the specific heat capacity plays NO role in the effectiveness of your cooling setup.

The only thing that matters, is the ability to transfer the heat from what your cooling, into the external environment.

In an air to air intercooler, you have one step, the ambient air cooling an alloy radiator, which in turn cools the intake air inside it.

Step 1. ambient air cools an alloy radiator(intercooler)
Step 2. Radiator cools intake air.


In a water to air intercooler there is an extra 2 steps of heat transfer,

step 1. Ambient air cools an alloy(copper?)
step 2. radiator cools the water flowing within it.
step 3. water cools an alloy radiator in the intake path.
step 4. alloy radiator cools the intake air.

Every step is subject to limitations on the rate of change of heat. Thus, the more steps you have the more time it takes for the heat to move from one end of the system to the other.

The only way you can increase the speed at which the heat transfer occurs is by more surface area. IE, bigger radiators. In most cases, a w2a radiator is mounted at the front of the vehicle, the same spot an a2a intercooler would be mounted, thus the size constraints are the same in both systems.

The origonal post asks for pros and cons of fitting said intercoolers to a 1hz powered 4wd. Only an idiot would take that to mean a dry ice setup. And then neglect to mention hes talking about dry ice when he touts water to air as the better system.

For cooling a 1hz, air/air IS the better solution, unless space constraints mean we can have a bigger radiator for the w2a system, ie, mounted in the tray.

Unless this is a dyno queen 1hz, in which case, you dont need a radiator, just a dry ice tank and a w2a intercooler.

I dont think its silly to setup a Good W2A system on a 4x4.

Just make it strong use quality parts and over engineer it the first time and you'll have no problem.

The biggest thing that steers me away from A2A is the decreased airflow to the engine rad and also possible mudding up of the core.
If your serious about setting up a good intercooler system on a 4x4 it will need to see best cooling efficiency at low air speed i.e crawling through mud/sand at 4000+ rpm and max load... only a W2A setup can do this.

B4 people start to get on their high horse again and say that the W2A setup wont be able to hold down intake temps in a sustained load situation, look at the second line...

An AU falcon radiator, shroud and thermos will remove any and all heat buildup after a sustained load.


Leave the A2A setups for the Ricers people....

Z()LTAN wrote:I dont think its silly to setup a Good W2A system on a 4x4.

Just make it strong use quality parts and over engineer it the first time and you'll have no problem.

The biggest thing that steers me away from A2A is the decreased airflow to the engine rad and also possible mudding up of the core.
If your serious about setting up a good intercooler system on a 4x4 it will need to see best cooling efficiency at low air speed i.e crawling through mud/sand at 4000+ rpm and max load... only a W2A setup can do this.

B4 people start to get on their high horse again and say that the W2A setup wont be able to hold down intake temps in a sustained load situation, look at the second line...

An AU falcon radiator, shroud and thermos will remove any and all heat buildup after a sustained load.


Leave the A2A setups for the Ricers people....

Decreased airflow at the radiator will be the same wether you put a a2a intercooler there, or the radiator for a w2a intercooler there.

A w2a intercooler can be muddied aswell you know?

And put those same AU thermos on an a2a intercooler and it will perform just as effectively.

I dont know why people think w2a are the holy grail of intercooling. They have thier segment, but it is really less to do with performance, and more to do with space.

yeah i was talking from a ute owners perspective as i would mount a W2A rad in the rear

So is this back on Topic yet???

Plenty of debate!!

If I had more room and i do now - I may have gotten a water to air solution. I'm keen to see how the laminova setups work under real use - not dyno runs but after the third boghole.

I'm changing my A2A setup soon enough - more so because I can and I have a mechanic thats keen to change it up which suits me fine!! hence I'm selling my whole turbo and A2A setup as it is - it's proven, responsive and works great - it's just not going to handle doubel the power output in the manner i want.

By changing - I mean it will be different.

Anyways - this has been a funny read and oddly heated topic...

is easier to cool air. harder to cool water down once it gets warm in the exchanger.