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View Poll Results: a2w ic, or fmic, or v-mount ic?
Air to water intercooler
28.89%
Front mount intercooler
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my custome A2W (air to water) intercooler all for only $300

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Old 03-02-10, 12:00 PM
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i Was thiking ways to monitor my air and water for my a2w setup. after see what u used i kept searching and found this. instead of using batt. it uses 12v.
i dont think i see were the sensors are put in unless its the wires hanging out of the coupler. i think im going to put 4 of them in. and have an idea for mounting them i think.
http://cgi.ebay.com/Digital-Thermome...item3a584a146d
Old 03-02-10, 02:16 PM
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Originally Posted by supak111
I understand what you mean as far as the radiator goes, I know it would be better up front. That doesn't worry me much, its very easy to move that now any where I like. BTW 2 radiators for the a2w would be better you just need to hook them up right. You have to connect the one in the engine bay first, when that one cools the water down some then from that one go to the front one that will cool it down even more, and from there you go into the a2w. But I think it might work fine where its now and here is why: I did a fan mod so my fans are cooling the engine radiator all the time which means the temp in the radiator will ALWAYS stay at or just above ambient temp (keep in mind hot coolant for engine inters the radiator on the pass side, by the time it get to the driver side where my setup is it already ambient or maybe lightly higher) which in turn means even though my a2w radiator is behind the engine radiator (on colder driver side) it too should stay the same temp. Another good point from above is if this will have enough cooling for the track? Very true and I don't know, this is what I have to test. I have a gauge for IAT and a gauge to monitor my water temp inside my a2w so I just got to fix my CEL light now before I give you guys those numbers. THANKS FOR PUTTING IN YOUR TWO CENTS EVERYONE, keep it up
There is a problem with this idea of hooking two up together this way. Its simple, the water in the air to water intercooler never reaches the temperature of the water in the radiator, its way cooler...even right after it runs through the intercooler core. So you are blowing air that is hotter into the core so in effect you are heating up the water from the A2W system with the air from the radiator, in order for something to cool you need two things:

1. a volume/flow of air and 2. you need a temperature differential.

In this case you have a negative temperature differential because the air you are blowing at the heat exchanger is hotter than the water going through it from A2W system so you are actually adding heat to the water instead of taking it away. In this case if you move that single core up front you will cool more effectively than if you leave it there and add another one up front because the one up front wont have to remove the heat that the one in the bay is adding.

I have had a system like this in my car for a while and there is a simple example that will help you understand what I am saying: Can you touch your engine radiator or the water in it while the car is running without getting burnt? no, you can't. to give you an idea, the water in your A2W system should only feel warm to the touch it should only be 10-20 deg above ambient as it enters the intercooler core and it should come out slightly above that but not boiling or extremely hot by any means, you should still be able to touch the water....if this is the case the air going through your radiator is coming out hotter than the water in your heat exchanger and then you are blowing it through which is actually heating up the water to a higher "steady state" temperature.

I know this for a fact...the fact that you have a heat exchanger and in which direction it actually "exchanges" heat depends on whether its hotter outside of it or inside of it.

Just my .02...move it up front and you will see a ridiculous drop in IAT's...and if you add another one, put them both up front....it will be better to have a single one up front than to have one up front and one behind the radiator...two up front would be best.

Chris
Old 03-02-10, 03:06 PM
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Yea I decided to put the a2w up front like I said but I'm going to get some #'s from this first just to compare them. I understand that the engine radiator gets hot and could add heat to my a2w rad, but I think it wouldn't with the fan mod because fans being always on should keep both radiators just above ambient temp
Old 03-02-10, 10:01 PM
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Originally Posted by supak111
Yea I decided to put the a2w up front like I said but I'm going to get some #'s from this first just to compare them. I understand that the engine radiator gets hot and could add heat to my a2w rad, but I think it wouldn't with the fan mod because fans being always on should keep both radiators just above ambient temp
Are you saying the fans with the mod are going to keep the engine rad temps just above ambient?
Old 03-02-10, 10:13 PM
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Originally Posted by ChrisRX8PR
There is a problem with this idea of hooking two up together this way. Its simple, the water in the air to water intercooler never reaches the temperature of the water in the radiator, its way cooler...even right after it runs through the intercooler core. So you are blowing air that is hotter into the core so in effect you are heating up the water from the A2W system with the air from the radiator, in order for something to cool you need two things:

1. a volume/flow of air and 2. you need a temperature differential.

In this case you have a negative temperature differential because the air you are blowing at the heat exchanger is hotter than the water going through it from A2W system so you are actually adding heat to the water instead of taking it away. In this case if you move that single core up front you will cool more effectively than if you leave it there and add another one up front because the one up front wont have to remove the heat that the one in the bay is adding.

I have had a system like this in my car for a while and there is a simple example that will help you understand what I am saying: Can you touch your engine radiator or the water in it while the car is running without getting burnt? no, you can't. to give you an idea, the water in your A2W system should only feel warm to the touch it should only be 10-20 deg above ambient as it enters the intercooler core and it should come out slightly above that but not boiling or extremely hot by any means, you should still be able to touch the water....if this is the case the air going through your radiator is coming out hotter than the water in your heat exchanger and then you are blowing it through which is actually heating up the water to a higher "steady state" temperature.

I know this for a fact...the fact that you have a heat exchanger and in which direction it actually "exchanges" heat depends on whether its hotter outside of it or inside of it.

Just my .02...move it up front and you will see a ridiculous drop in IAT's...and if you add another one, put them both up front....it will be better to have a single one up front than to have one up front and one behind the radiator...two up front would be best.

Chris
I'm not sure that this is correct. Maybe it is in some cases. You mention touching your hand to the radiator or water in the radiator and it being too hot and causing a negative temp differential. I see the logic there, But...

I think the assumption of a negative temperature differential is incorrect (especially if under heavy load with high boost). The water in the radiator is not what is passing through the heat exchanger for the W2A intercooler (so it doesn't matter if that has a high enough temp that can burn you or not). The air that has gone through the radiator is what is doing the work. Yes, after passing through the radiator it has gained a good deal of heat, but it will definitely not burn you. Now compare the temperature of that air to the air that is coming out of the turbo (heated by the turbine). I bet there is still a positive temperature differential (especially under load when the turbine is really heating up the intake air).

So I'm betting that even with the heat exchanger being behind the radiator and utilizing the heated air it is still reducing the heat of the intake air. But of course not as efficiently as it could if the heat exchanger was in front of the radiator and receiving cold air.
Old 03-03-10, 02:23 AM
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Yes I am saying that if you put your fans on full speed all the time the temps in the engine radiator will be ambient or just a little bit above the ambient temp.

Now before you say I'm wrong let me explain. HOT coolant from the engine enters the radiator on the passenger side, by the time it gets to the other side (driver side) of the radiator the coolant is it should already be down to ambient or just above. If you look my a2w rad is on the driver side which is the cold side of the engine rad, I deliberately placed it there.

Only way I see the the coolant on the driver side (cold side) of the car radiator get way above ambient is if your car is not moving (so there is no air flow) and if the fans are off then. I'm not disagreeing that a2w in the front isn't batter, of course it better, I'm just saying it should be that much different with the FAN MOD.

Originally Posted by BluRR
Are you saying the fans with the mod are going to keep the engine rad temps just above ambient?
Old 03-03-10, 10:24 AM
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Originally Posted by supak111
Yes I am saying that if you put your fans on full speed all the time the temps in the engine radiator will be ambient or just a little bit above the ambient temp.

Now before you say I'm wrong let me explain. HOT coolant from the engine enters the radiator on the passenger side, by the time it gets to the other side (driver side) of the radiator the coolant is it should already be down to ambient or just above. If you look my a2w rad is on the driver side which is the cold side of the engine rad, I deliberately placed it there.

Only way I see the the coolant on the driver side (cold side) of the car radiator get way above ambient is if your car is not moving (so there is no air flow) and if the fans are off then. I'm not disagreeing that a2w in the front isn't batter, of course it better, I'm just saying it should be that much different with the FAN MOD.
not a chance mate im afraid, theres no way even with full fan speed you can change the water from 90c to 30c through that rad, to take 60c out of water takes a massive amount of doing, basically your saying your could unplug the outlet pipe off your rad and let the water flow onto your hand and it be just a little warm, not gonna happen
Old 03-03-10, 01:32 PM
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Originally Posted by turbotoaster
not a chance mate im afraid, theres no way even with full fan speed you can change the water from 90c to 30c through that rad, to take 60c out of water takes a massive amount of doing, basically your saying your could unplug the outlet pipe off your rad and let the water flow onto your hand and it be just a little warm, not gonna happen
+1
It doesnt cool that quickly at all. No way in hell. Once your car is running you are gonna be running anywhere above 80c+ most go 90 to even 100c. It will no cool that quickly at all.
Old 03-03-10, 01:49 PM
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i've never really understood the point of an A2W IC on street cars.

on a boat...sure: you're always using new water (i.e. it's not a closed loop system, so the temp of the water going into the ic doesn't increase over time).

on a really tight car...sure: you're limited on space and the A2W IC allows you to mount a smaller IC close to the turbo/throttle-body, minimizing intercooler piping, while mounting the additional radiator elsewhere.

but on a car with a tiny engine in a decent sized engine bay? why!? all you're doing is adding additional links to the chain: now you need a second radiator, now you need more hoses, now you need more coolant, now you need an additional pump (that draws current from the electrical system)...

the reality of it is that the water in the system can never be cooler than the ambient air temp unless you're using a really, really good radiator that is constantly getting good airflow. after a short period of time, the water temps will rise, and the cooling power of the IC is only going to be as effective as the cooling power of the radiator. in this guys case, he's used a really cheap (and small) radiator from a quad - which i'm sure is not as efficient as a normal A2A intercooler.

until i see some temps, i don't see how this A2W setup could perform better than a front-mount, V-mount, or ducted-SMIC setup.

i say, stick with what works: good old air2air intercoolers.
Old 03-03-10, 04:17 PM
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Yea it may not cool that fast you guys make a good point. I can easily test the temp of the car radiator on the hot pass side and the cooler driver side and I can tell you but I don't car at this point. I'm gonna just get my IAT and a2w water temps #'s and then try the up front rad setup
Old 03-03-10, 07:59 PM
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Originally Posted by turbotoaster
not a chance mate im afraid, theres no way even with full fan speed you can change the water from 90c to 30c through that rad, to take 60c out of water takes a massive amount of doing, basically your saying your could unplug the outlet pipe off your rad and let the water flow onto your hand and it be just a little warm, not gonna happen
But it doesn't matter what the coolant temp is of the cars radiator, what matters is the air that has passed through that radiator and now hitting the A2W's exchanger. It will still be cooler than the air that was heated up by the turbo under boost won't it? Therefore there will still be a positive temperature differential and will help to cool the fluid in the A2W system that is absorbing heat from the intake air which was heated by the turbo.

Yes the heat exchanger would be better if placed in front of the radiator, but i don't understand why everyone keeps referring to the fluid inside of the radiator. (yes that heats the air that passes through the radiator, but not as much as the the turbo has heated the intake air)

After a hard pull at 18 psi, the pre-intercooler intake piping is too hot to hold your hand on (on my car anyways), yet the air coming through the radiator won't burn anything.
Old 03-04-10, 10:24 AM
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I agree with the post above.. But we are talking about making this thing a2w cool the iat temp as close to ambient as possible. That's my goal at least ;-). I'm also planning on adding a bypass valve and a water cooler with ice and maybe bunch of peltier cooler to make this thing do 40 50 below ambient. I got ideas and like I said I'm mainly doing this for fun
Old 03-04-10, 10:29 AM
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Originally Posted by Chudsoncoupe
I'm not sure that this is correct. Maybe it is in some cases. You mention touching your hand to the radiator or water in the radiator and it being too hot and causing a negative temp differential. I see the logic there, But...

I think the assumption of a negative temperature differential is incorrect (especially if under heavy load with high boost). The water in the radiator is not what is passing through the heat exchanger for the W2A intercooler (so it doesn't matter if that has a high enough temp that can burn you or not). The air that has gone through the radiator is what is doing the work. Yes, after passing through the radiator it has gained a good deal of heat, but it will definitely not burn you. Now compare the temperature of that air to the air that is coming out of the turbo (heated by the turbine). I bet there is still a positive temperature differential (especially under load when the turbine is really heating up the intake air).

So I'm betting that even with the heat exchanger being behind the radiator and utilizing the heated air it is still reducing the heat of the intake air. But of course not as efficiently as it could if the heat exchanger was in front of the radiator and receiving cold air.

If your Air to Water is designed/built properly the water going through it will only be a little above ambient and a lot less temp than the air that is coming out behind the radiator. At full blast while you are driving that air coming from the rad is pretty hot...you're right, it will not burn you but its not even close in temp to the water in the Air to Water system which just feels slightly warm to the touch.

I see what you are saying...but the water in the A2W system is still way cooler than the air coming out from the radiator by a whole lot, I am talking 50-60 degrees different.

Chris
Old 03-04-10, 01:08 PM
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Originally Posted by theorie
....until i see some temps, i don't see how this A2W setup could perform better than a front-mount, V-mount, or ducted-SMIC setup.

i say, stick with what works: good old air2air intercoolers.
+1.
I appreciate the imagination and workmanship with the OP's setup, but it seems like he's re-invented the wheel for no good reason. It actually seems heavier, more complex and possibly even less efficient than a decent sized well-ducted aftermarket a/a IC. Especially for a streeted car.
Old 03-05-10, 01:26 PM
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One more time, stock ic sucks! It's only 12" x 6" x 3" = 216ci. What makes it even worse is the way it's ducted. The ducking has a huge bottle neck where it's only 12" wide and only 2" tall. So not only is the ic small but they didn't even duct enough air to use this tiny thing to it's full potential. Even if they had the full 12" x 6" of air duct to it I still don't think its enough IC for a rotary engine that uses a lot of CI of air per minute
Old 03-05-10, 03:48 PM
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I wasn't comparing it to the stock IC. I don't think anyone was.
Old 03-17-10, 03:18 AM
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I've decided to do a full car radiator (probably like a honda civic's) and putting it up front for cooling the water for the a2w. With a radiator that big, & the size of my a2w core, and a 600gpm water pump, this setup should be able to handle 500hp easy and keep the temps at or just above ambient even at full boost for a long time
Old 03-17-10, 10:07 AM
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vmount or sandwiched? Have you considered an atv radiator from ebay?
Old 03-18-10, 02:54 PM
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It's an atv radiator on there now, it's about 15" x 12" x 1", this it might be small but still haven't done temp testing. Car will be fixed soon hopefully and I'll give you guys the #s
Old 04-08-10, 07:07 PM
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Finally got some temp numbers for everyone
Old 04-08-10, 08:22 PM
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and?? where are they?
Old 04-08-10, 10:18 PM
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Finally got some temp numbers for everyone

I finally got my car running good. I installed a PFC and I the car drivers great. Disconnected the bad OMP and running premix now. My a/f ratio is better, idle isn't rich anymore, while pushing the car a/f stays at about 13 to 1 which is great... I love the PFC, I can't say enough good things, I would recommended it as a first mod on your FD to anyone.

Now the temp numbers. I took the car on the highway for about an hour there and hour back. I tried pushing it and just cruising.

Ambient temp that day was 75 degrees F.

CRUISING TEMP's
While cruising my IAT was between 130-140F
Water temp inside my a2w setup (cold side after radiator) was 120F


BAD: Now I know my a2w water temp is pretty high and its obvious that I need to put the radiator up in the front of the car radiator so that the car's radiator DOES NOT heat up my a2w radiator which is what is happening now. Plus if I put the a2w radiator in the front it will get the coolest (ambient) air to cool it, in this case 75F air would make the contact with my a2w rad if my a2w rad was in the front that is.


BOOST TEMP's (on my car boosts 14psi now with stock twins no boost controller)
While boosting the car the IAT temp was at 140F to 150F (only about 10 degrees higher the cruising)
Water temp inside the a2w (again after the a2w radiator) was 125F (only 5 degrees higher then cruising)

GOOD: As you can see my setup cools the air pretty good, difference between cruising and boost was only 10 degrees higher. So in theory when I put the a2w radiator up from my a2w setup should keep the intake air temp at boost only about 10 degrees higher then my a2w water temp which also in theory should stay at or just above ambient temps. Now this was not track driving where you are constantly boosting (those number I'm sure would be higher and I might get them later) but as you can see a water to air setup on a daily driver works just fine.

I'll be doing more testing soon and give you guys more #'s. I will also put the radiator up front and I will be adding an additional 8x7x2" all copper heater core for extra cooling. I will have the aluminum radiator I have now and will put that up in the front grill, and I will install the heater under the passenger headlight (where the second oil cooler is on R1 model). That spot is very nice because its far away from engine heat and it has its own opening for cool air.

So hot a2w water will go from intercooler to the aluminum radiator that is now up front, it will exit the the radiator way cooler, and then enter the full copper heater core (keep in mind copper has about 70% higher thermal conductivity so it should cool A LOT better then the aluminum rad) then the a2w water will exit the copper rad and back into the intercooler at temperatures of ambient or just above ambient. I really believe with 2 radiators setup like this they should be able to bring that a2w water down to ambient even with HARD HARD driving at the track. I wanna over do it with the 2 radiators because if there is enough surface area on your radiators your a2w water should be at ambient all the time no matter what PSI your boost or for how long you boost.
Old 04-09-10, 06:37 PM
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Thanks for the data supak. I'm making my choice where to take mine this week.

Anybody have any numbers on their a2a intercoolers?
Old 06-09-10, 07:13 PM
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is say a2w is better if rad is placed properly, also you can put in a resivoir and add ICE if you want to hit the track, that is a real benifit...
Old 06-10-10, 03:42 PM
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Oh I haven't update this thing yet but my setup is sick now (I'll post some new pics later). I have two radiators, still got the big aluminum atv rad but now up front now, then from there water goes to the right (pass side) into a really big full copper heat core that I installed where the R1 modes have the second oil cooler then from there into the a2w intercooler. My water temps ever go past 90F even when pushing the car on 85F day and my car boosting 17psi on stock twins. The highest my Power FC commander ever shower is 48C which is about 120F intake temp but thats at the stock intake air temp sensor which gets a lot of heat from engine actually being hot so thats usually higher then what the intake air temp really is


Quick Reply: my custome A2W (air to water) intercooler all for only $300



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