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wjp005 04-26-09 08:05 AM

My Water to Air Setup - Australia
 
OK so I've recently just finished my water to air intercooler setup and I thought I'd share it with you guys.

I hadn't washed the car in about 7 months! It was sitting in the shed patiently waiting for me to finish and had copped a fair layer of dust, even with a cover over it!

My main reasons for doing this:

1. Clear air to radiator <- Main reason
2. Shortest possible intake pipes (less lag) as less air to pressurise every time the turbos boost
3. Less pressure drop than air to air coolers as core is much, much smaller
4. Water is more than 4 times more efficient at removing heat than just air
5. Reduce heat soak at low speeds (as chilled water will be still circulating, even if the car is stationary)
6. I will be able to get air intake temps BELOW ambient, the best you can EVER hope for with FMIC / SMIC is to match ambient but this is usually not possible.
7. I like being different, haven't seen this done too often as most people think it's too complicated.


Here's some pictures of the engine bay setup.

Check out how short I've been able to keep the pipe work! Less air volume than OEM.

http://i634.photobucket.com/albums/u...r/DSC_5162.jpg

http://i634.photobucket.com/albums/u...r/DSC_5164.jpg

http://i634.photobucket.com/albums/u...r/DSC_5166.jpg

http://i634.photobucket.com/albums/u...r/DSC_5172.jpg

I just ran 13mm poly lines to the boot, where I mounted an ordinary esky to the floor and will be adding ice before I run.

Water pump used is just an ordinary bilge pump. It flows plenty of water 400 GPH and is 12vdc.

To be safe I've put some mesh in to the floor if the esky to prevent chuncks of ice blocking the pump / lines.

I plumbed in 2 taps to the return line to allow me to pump the warm / hot water after a run out the back of the car (I ran a line inside the rear quarter and poked it out near the bumper)

http://i634.photobucket.com/albums/u...r/DSC_5157.jpg

http://i634.photobucket.com/albums/u...r/DSC_5158.jpg

http://i634.photobucket.com/albums/u...r/DSC_5176.jpg

http://i634.photobucket.com/albums/u...r/DSC_5177.jpg

I mounted a switch to operate the relay controlling the bilge pump next to my steering wheel:

http://i634.photobucket.com/albums/u...r/DSC_5181.jpg

And that's about it. If I need to later on I can plumb in an extra heat exchanger to keep the water cool for longer periods of time ( AC condensor or small radiator, oil cooler, etc)

For now as I'm only doing fairly short bursts in the car, I think just the ice box will be fine. I can use just normal crushed ice or if that melts too quickly I'll use large blocks which will take more energy to melt.

The car will be going to a 2 day event (hillclimb / supersprint) at tamworth on 2nd and 3rd of May. I'll let you guys know how I get on.

Some other pics:

http://i634.photobucket.com/albums/u...r/DSC_5193.jpg

http://i634.photobucket.com/albums/u...r/DSC_5195.jpg

http://i634.photobucket.com/albums/u...r/DSC_5207.jpg

NissanConvert 04-26-09 10:18 AM

For short bursts that will be fine. I must admit i was a bit concerned when i saw that it was a race car. If it were a DD i'd recommend another radiator to drop the temp of your water on longer drives.

neit_jnf 04-26-09 01:32 PM

interesting! not for dd though

dis1 04-26-09 01:42 PM

Very interesting, I love seeing custom ideas. Love the hood too.

Brent Dalton 04-26-09 06:10 PM

Very cool setup... no pun intended :D Interested to see what your results are at your 2 day event. How much faster is spool?

Sandro 04-27-09 05:51 PM

Thank you for sharing this information.

I am planning on a similar system.

Is the IC a 3.5" core with 2.5" air I/O?

- Sandro

wjp005 04-27-09 06:29 PM

It's a 3.5" core with 2.5" inlets/outlets. I used 3" pipe work.

Cooler came from these guys: http://www.frozenboost.com/product_i...df64a98cef9aea

:icon_tup:

Sandro 04-27-09 06:51 PM

Thanks.

Yes, I got their Type 13
http://www.frozenboost.com/product_i...90f2fee988f2bd
as I would like to retain the stock air box.

I tried with a 4.5" core but there was no way to locate it under the hood and keep the air pipes short.

I am still trying to figure out how to anchor the IC to the cross member solidly though. But my biggest problem right now seems to be how to route the water hoses to the rear. Rules won't allow me drilling or enlarging holes on any body panels. I just removed most of the A/C and planning on using the two holes through the firewall, but still have to find the time to remove the entire dashboard without breaking anything...

- Sandro










Originally Posted by wjp005 (Post 9162695)
It's a 3.5" core with 2.5" inlets/outlets. I used 3" pipe work.

Cooler came from these guys: http://www.frozenboost.com/product_i...df64a98cef9aea

:icon_tup:


catch-22 04-27-09 07:28 PM

did you use a drink cooler in the back????

wjp005 04-27-09 09:08 PM


Originally Posted by Sandro (Post 9162748)
Thanks.

Yes, I got their Type 13
http://www.frozenboost.com/product_i...90f2fee988f2bd
as I would like to retain the stock air box.

I tried with a 4.5" core but there was no way to locate it under the hood and keep the air pipes short.

I am still trying to figure out how to anchor the IC to the cross member solidly though. But my biggest problem right now seems to be how to route the water hoses to the rear. Rules won't allow me drilling or enlarging holes on any body panels. I just removed most of the A/C and planning on using the two holes through the firewall, but still have to find the time to remove the entire dashboard without breaking anything...

- Sandro

Yeah, I ran my water lines though the holes where the heater pipes came into the car, seemed like a good spot...

Would love to see some pics of your setup Sando. Pls post. :)

Sandro 04-27-09 09:21 PM


Originally Posted by wjp005 (Post 9163214)
Yeah, I ran my water lines though the holes where the heater pipes came into the car, seemed like a good spot...

Would love to see some pics of your setup Sando. Pls post. :)

Well not that much to take picture of, right now... At my pace, expect a long, long time to show any material progress...

But I will certainly keep you posted.

Thank you again for the great information.

- Sandro

Sandro 05-28-09 01:01 PM


Originally Posted by wjp005 (Post 9158507)
....The car will be going to a 2 day event (hillclimb / supersprint) at tamworth on 2nd and 3rd of May. I'll let you guys know how I get on....

So, how did it go?

- Sandro

Indian 05-28-09 03:26 PM

Nice setup. I'm running the precision pt1001 with a custom aluminum tank. I run a rule 2000 pump and 1" line through out the car. I'm going to add an oil cooler to help with heat when on the street


I'll try and get some pictures up.

M104-AMG 05-28-09 04:53 PM

Do you have water or meth aux. injection (AI) ?

I think high-definition (HD) AI with methanol or water would work wonders for a hill-climb car, where you want to modulate the power.

Regardless, nice work!

:-) neil

wjp005 06-03-09 11:24 PM

Well, the car went great guys and I kicked some serious arse! 11th outright of a field of ~60 cars including open wheelers, sports sedans, AWD cars, etc. Only 3 tin tops beat me!

I've made a video of it, link is below after my pictures. (My brother in law has the white WRX STI RA)

After a run the cooler core had condensation on it like your cold beer as soon as you take it out of the fridge!

Touching the core was amazing at what temp it was. The pipes in to, and out of the cooler were DRAMATICALLY different in temperature. Ambient air temps were 21 deg and I had intake air temps ranging from 12-14 deg just before the throttle body.

In the pits after a run I left the icy water circulating to keep everything cool. Let's see you do that with a FMIC while the car is stationary!

Sloshing wasn't an issue, although I did tape up around where the lid seals. Think I will get a block of polystyrene foam to put over the ice as I was only running with the esky a bit less than half full. About 100mm liquid depth and 50mm layer of ice on top worked well.

I was surprised at how quickly the ice did melt, as the water coming back was around 40 deg C. So it's certainly doing it's job very well and removing a lot of heat.

Had a lot of interest in the setup. Heaps of people wanting to know more.

I'm amazed that these types of coolers aren't used more often as they are SO much more effective than any other form of intercooling out there.

I'm keen to take the car to WSID and do a 1/4 mile pass in the coming weeks just to see what the car puts down.

Anyway, here's some pics:

http://i634.photobucket.com/albums/u...esPearson3.jpg

http://i634.photobucket.com/albums/u...CalebRees1.jpg

http://i634.photobucket.com/albums/u...getJobber1.jpg

http://i634.photobucket.com/albums/u...t/GTRvsWRX.jpg

http://i634.photobucket.com/albums/u...esPearson1.jpg

http://i634.photobucket.com/albums/u...esPearson2.jpg

http://i634.photobucket.com/albums/u...inEdwards2.jpg

And here's my video I made of the occasion: http://www.vimeo.com/4688352

Nateness 06-04-09 12:30 AM

Wow, thanks for sharing this info and pictures. Gorgeous cars! Beautiful scenery!

just startn 06-04-09 01:09 AM

After seeing this it really made me want to do air/water. I have been pondering lately about this but actually visualy seeing a setup im totatly going to try. My cars not a race car but not a DD just a nice day driver so no im thinking ALOT on how to make it more "streetable". ANyone have any ideas to make a system like this streetable? adding a radiator and a bigger "ice box"is the only thing i can think of lol.

wjp005--Do you know what that bilge pump is for or out of? any type of jet ski? How did you come about getting THAT one and were did you pick it up from? Im really really really really interested in experimenting with this.

Nateness 06-04-09 01:51 AM

To make this "streetable" you'd need to mount a seperate mini-radiator for the A/W IC.

The major draw-backs to this particular system:

1) Operational period only lasts as long as the ice does, once the ice is gone, the system will be worse than stock. You can add a heat exchanger in the line, which could prolong the period of time under which sub-ambient IAT's could be achieved. Ultimately you would be limited to some steady-state IAT temperature that is above ambient if you cannot replenish the ice when it all melts (which would make the system arguably equivalent to A/A, depending on individual setups).

2) Reliability inherantly is decreased since additional components have been added beyond what an A/A system would have. You have to be careful to look out for pump or hydronic line failure.

I see this being ideal for drag racers and people who are able to constantly refill the ice supply (though you'd have to remove water volume at the same time). Looks like it works brilliantly for what the original poster is doing, but I'd be hesitant to use it on a street driven car (though Toyota pulled it off with their ST205 Celica GT-4's).

Sandro 06-04-09 09:09 AM

That is fantastic!

Thanks for sharing.

I assume it was a time trial around the track. How many seconds? And how much ice did it consume? I would like to confirm that a similar sizing would be adequate for my application. Our typical autox runs are 60 sec or less.

Good work!

- Sandro

wjp005 06-04-09 05:52 PM


Originally Posted by Sandro (Post 9264060)
That is fantastic!

Thanks for sharing.

I assume it was a time trial around the track. How many seconds? And how much ice did it consume? I would like to confirm that a similar sizing would be adequate for my application. Our typical autox runs are 60 sec or less.

Good work!

- Sandro

Yeah, time trial around track. We went out for 5 lap sessions, in which time I melted about 12 litres of water with 6kg ice on top. Although the ice completely melted, the water was still cold. And I let the water circulate well before I went on to the track (to chill the cooler) and well after my timed session to cool everything.

Each session involved almost a complete lap warmup, 3 timed laps and almost a complete lap cool down. Lap times were about 43 seconds.


Originally Posted by just startn (Post 9263710)

wjp005--Do you know what that bilge pump is for or out of? any type of jet ski? How did you come about getting THAT one and were did you pick it up from? Im really really really really interested in experimenting with this.

Bilge pump was just bought from a boating/camping place. It was the most suitable for what I'm doing. Importantly it is self priming, and flows WELL in excess of what I needed. Generally, pumps for w2a setups need flow around 12/15 litres per minute, this bilge pump I'm using flows 400 gallons per hour, which is ~25 litres per minute, so I'm circulating the water far more rapidly than I really need to be (about twice as fast) which contributes as to the speed in which I melt the ice.

I may look at adding a speed controller to the pump but for now (as I'm doing short runs with the car) the setup is great for me. :icon_tup:


Originally Posted by Nateness (Post 9263806)
To make this "streetable" you'd need to mount a seperate mini-radiator for the A/W IC.

The major draw-backs to this particular system:

1) Operational period only lasts as long as the ice does, once the ice is gone, the system will be worse than stock. You can add a heat exchanger in the line, which could prolong the period of time under which sub-ambient IAT's could be achieved. Ultimately you would be limited to some steady-state IAT temperature that is above ambient if you cannot replenish the ice when it all melts (which would make the system arguably equivalent to A/A, depending on individual setups).

2) Reliability inherantly is decreased since additional components have been added beyond what an A/A system would have. You have to be careful to look out for pump or hydronic line failure.

I see this being ideal for drag racers and people who are able to constantly refill the ice supply (though you'd have to remove water volume at the same time). Looks like it works brilliantly for what the original poster is doing, but I'd be hesitant to use it on a street driven car (though Toyota pulled it off with their ST205 Celica GT-4's).

Thanks for your comments but I disagree partially mate and hope you don't mind me offering the following response. While most of what you said is correct, alot of it is your opinion and speculation. Don't forget all the BENEFITS of using a system like this listed at the top of this thread.

Firstly, you are incorrect in saying that the system no longer operates once the ice is gone. Even with no ice the water will still be chilled, and still EXTREMELY efficient at removing heat from the pressurized air entering the core. The water doesn't increase in temperature very rapidly and even just room temperature water will remove heat far more efficiently than ambient air flow in the case of an air to air setup. (You don't put iced water into your radiator do you?!?!?)

Secondly, this setup isn't compromising reliability as much as you suggest. The only real point of failure is the pump and related electrical control system. Even if it did fail, providing one quickly noticed, the water core is still chilled for a resonable amount of time after water circulation has been shut off and no major consequences would result. What about the fuel pump failing? just as likely with results much more dire!

Toyota weren't the only ones to use this much more efficient and cleverer way of intercooling. Subaru used a factory water to air system on early RS liberty / legacy cars.

Also please remember any intercooling system is only in use under BOOST conditions, which on the street is what percentage of the time? If one wanted to use a w2a system in a street car, it would seem appropriate to develop a boost related system (possibly controlled by ECU) that went from a very low speed circulation under normal conditions to higher speed circulation under boost.

I will possibly look at adding in an additional heat exchanger to the system (probably an AC condensor with fan or oil cooler) to increase operational time for prolonged racing but for now it does the job I intended it to do extremely efficiently and I'm very happy. :icon_tup::icon_tup:

scrip7 06-04-09 09:14 PM

This is what I will be using in my FC for a heat exchanger. It's a radiator with fan and shroud from an Arctic Cat ATV. Has a typical radiator cap for filling and for maintaining system pressure. 1 inch inlet and outlet nipples. It fits perfectly to the left of the hood latch on my FC.....not sure what kind of room you would have for it in your FD though so my rambling may be pointless, but here are pics:

[IMG]http://i159.photobucket.com/albums/t...owaxAWS369.jpg[/IMG] [IMG]http://i159.photobucket.com/albums/t...owaxAWS370.jpg[/IMG] [IMG]http://i159.photobucket.com/albums/t...owaxAWS371.jpg[/IMG]

wjp005 06-04-09 10:34 PM

Looks good mate.

If I end up plumbing a heat exchanger in, I'll most likely use an A/C condensor and mount it in the boot with a fan (or under the back of the car)

The temperatures of water dealt with are nothing like in a coolant system of a car, so there's no need for massive amounts of airflow over the core (unlike most people's assumptions :rolleyes: )

For now I think I'll just stick with my ice setup as it suits best for the track (if I was driving my FD on the street it would be a different story).

Good luck with your setup mate, post some pics up as you go or when you're done! :)

Nateness 06-04-09 10:44 PM


Thanks for your comments but I disagree partially mate and hope you don't mind me offering the following response. While most of what you said is correct, alot of it is your opinion and speculation. Don't forget all the BENEFITS of using a system like this listed at the top of this thread.

Firstly, you are incorrect in saying that the system no longer operates[ once the ice is gone. Even with no ice the water will still be chilled, and still EXTREMELY efficient at removing heat from the pressurized air entering the core. The water doesn't increase in temperature very rapidly and even just room temperature water will remove heat far more efficiently than ambient air flow in the case of an air to air setup. (You don't put iced water into your radiator do you?!?!?)

Secondly, this setup isn't compromising reliability as much as you suggest. The only real point of failure is the pump and related electrical control system. Even if it did fail, providing one quickly noticed, the water core is still chilled for a resonable amount of time after water circulation has been shut off and no major consequences would result. What about the fuel pump failing? just as likely with results much more dire!

Toyota weren't the only ones to use this much more efficient and cleverer way of intercooling. Subaru used a factory water to air system on early RS liberty / legacy cars.

Also please remember any intercooling system is only in use under BOOST conditions, which on the street is what percentage of the time? If one wanted to use a w2a system in a street car, it would seem appropriate to develop a boost related system (possibly controlled by ECU) that went from a very low speed circulation under normal conditions to higher speed circulation under boost.

I will possibly look at adding in an additional heat exchanger to the system (probably an AC condensor with fan or oil cooler) to increase operational time for prolonged racing but for now it does the job I intended it to do extremely efficiently and I'm very happy. :icon_tup::icon_tup:

Its ok to disagree, there is more than one way to open a door ;)

1) Without a water to air heat exchanger, your cooling potential is limited to the mass of the ice you put into the system. Once the ice is gone, you will begin to boil the water (until pressure eventually forces an opening somewhere in the system). I have no idea how long it will last without actually doing an energy balance on your setup. Could never be a problem, could be a problem, like I always say when I engineer something: you cant say for sure without doing the math. Relying on the thermal mass of the core to carry you home once your ice box has reached ambient temperatures isnt something that would make me feel comfortable. Water may be 4x more efficient at heat transfer, but once the water's temperature matches ambient temperatures, you're no better off than you were with air to air, only you've got a core that is about 4x shorter than an a/a. Not that it will matter because the water mass will likely only spend a very short period of time near ambient as it transitions to some higher temperature.

I really hope you were not serious about the radiator analogy (there is a fundamental difference between having an external heat exchanger and having a box of ice, infinite vs. finite heat sinks... you'll never run out of ambient air for your radiator...) :tonque:

2) I will have to stand by my statement that whenever you add components to a system, its reliability is reduced by some level. (more parts means more ways for a system to fail).

I haven't forgotten that boost pressure is what heats up the air, but I also havent forgotten how much heat the charge air gains by simply passing through the turbocharger assembly, even under idle (energy that is transfered to the turbine is transfered to their airstream going through it). Try cruising around town with no intercooler (with no boost) and see what your charge temps do.

All that being said, its a neat set up and its always good to see innovation. :icon_tup:

wjp005 06-04-09 11:00 PM

Agree, more than one way to skin a cat. :)

I would rather keep this thread free of complicated thermodynamic equations. I will simply address your comments by saying I have done my research and do know a little about what I'm doing. Ultimately I measure success via lap times on the track and take my calculator with a grain of salt.

Complicated? in an FD? Couldn't do the job any better than Mazda factory engineers did, exhibit a: OEM boost control design, your honor.....

Appreciate your comments and constructive criticism. It's always interesting to hear other peoples opinions. Such is the enjoyment with forums like these. :icon_tup:

just startn 06-06-09 08:31 PM

ok so you had 3 gallons of water and 13 pounds of ice and it all melted in lets say 2min? is that correct? b/c you refilled it each time correct?





[QUOTE=wjp005;9265562]Yeah, time trial around track. We went out for 5 lap sessions, in which time I melted about 12 litres of water with 6kg ice on top. Although the ice completely melted, the water was still cold. And I let the water circulate well before I went on to the track (to chill the cooler) and well after my timed session to cool everything.

Each session involved almost a complete lap warmup, 3 timed laps and almost a complete lap cool down. Lap times were about 43 seconds.


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