I just finished my monster water to air intercooler setup. Spend only about $300 for everything including a huge a2w ic, water pump, aluminum piping, radiator, coolant hoses. There is a lot of pictures and HOW-TO at http://trydeal.com/rx7/

Comments, suggestions, and questions are more then welcome. I'll help anyone when I find the time. Thanks everyone




Here is a picture of my custom air intake temp on the right (IAT after the water intercooler), and on the left water temp inside my a2w lines (after its cooled down by the radiator). I know gauges are kinda ghetto, but they are only $2 each, easy to install, and small enough so I can still see my whole cluster.

 

have you got any temps for it yet, just thinking it may struggle if the air has to pass throught the radiator first before it gets the a2w rad, could you reverse them around you think?

 

looks good. curious what your temps are, and congrats on having an idea and following through. now get us those numbers!

 

yea you can put the a2w radiator in front of the engine and ac radiator, it would be better cooling there, but there are no good mounting points up front and you have to run longer coolant lines. I found this easier and with the fan mod I can turn on my fans anytime I need more cooling for the a2w radiator. My a2w radiator is right above the fan so when I turn them on they help a lot. I don't have any temps yet, got a check engine light now and got to fix that first before any hard runs. I'll post them on my website as soon as I get them

 

Well done. I'd love to see some more numbers on this setup. Hell I'd buy one if the performance is good. This could be big even if it ends up only being a bit better than stock!

 

I wish I could find some intake air temp numbers from a stock RX7. I suspect the tiny stock intercooler probably has intake are temp somewhere about 100-120F over ambient, I am sure my a2w setup will be no more then 60F over ambient temp. 60F drop in intake air temp is about 9% HP or about 30hp + less of a chance of detonation and lower pressure drop... If you ask me that is some awesome stuff for only $300. If my temp goes above 60f ambient I'm adding a bigger radiator or use this one and put it up front in the grill or maybe both

 

Please let us know your long term experiences.

 

I suggest that if you don't have dual oil coolers that you move the heat exchanger core to under the passenger side headlight. The core may be to big. if you where to buy a core that was smaller in height and width that is thinker would work out much better for cooling. Very cool project though, makes mew want to ditch my standard intercooler.

 

I don't have a dual oil cooler. Are you talking about actually putting the a2w intercooler core there or the radiator for the IC? I don't want to put anything there because I have it set up where cold air come through that into my air filter. I'm making a cold air box next for my filter and all the cold air from underneat the right headlight is gona shoot right into the box so that alone should drop my temps down another 10-30F.

 

put the heat exchanger (yes the rad for intercooler) in the unused area where the other oil cooler would be on the passenger's side. Would yield even better results being out of the hot engine bay and in a direct high pressure area filled with delicious cool air.

 

I'm probably gonna end up adding another radiator up front before the ac rad, 2 will give me enough cooling for anything hp I throw at the engine

 

How long does the temperature take to get back down after you romp on it for a few gears and load up your medium with heat?

 

That's the real question..... Does it work for extended abuse not just putting around. I'd be interested to see how it holds up during a track session. Design looks pretty interesting though. I considered doing something similar with the PWR air to water IC.

-Dan

P.S. Get rid of those headlights.

 

You will be blowing hot air to the heat exchanger...this is what cools your charge...this means your charge will not be cooler than the air coming from the radiator fan which is pretty hot and above ambient. the Heat exchanger has to received unheated air from ambient for this to work, I know because my last setup was very close to this.

Adding a heat exchanger up front and keeping the one on top of the radiator fan will not help either, the one on top of the fan will heat the water that the one up front cools to near ambient, so in this case two is not better than one. You have to think of this just like you think of an air to air unit, you wouldn't put it behind the radiator, right? The same applies right here. Your system has the potential to work marvelously like mine did, it was even better than a front mount, but you need to move your heat exchanger.

Props!

Best regards,
Chris

 

It will work if combined properly and with the components in their proper location. I had 500+ whp on my setup and I actually saw a considerable drop in IAT's of like 10-15Deg across the board when I went to the air to water and I didn't even have a reservoir, just constant circulating water and a filler neck. If your heat exchanger is large enough and your pump flows enough you don't need the "bandaid" of an ice box, it will reach steady state at close to Ambient IAT's.

What I noticed at first that seemed weird and then it made sense later was the fact that with the FMIC the IAT's woudl rise when I was at a stop light, as soon as I got moving they would drop. With the Air to water, they actually dropped further when you're stopped. This made sense later since at a stop light or in traffic the fan in the heat exchanger kept pulling air, the engine wasn't boosting, the pump kept flowing water so it actually dropped in temps..it was pretty cool.

Chris

 

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

 

i understand your fan mod, basically its like having the a/c button pressed permanently even if you havent got a/c, keeps your fans running all the time.

the only concern there is your water temps(car) in your system should be around 85c cruising and 95c giving it beans.

Now that heat has to go somewhere to maintain a constant temperature, which the fans will do, but then that heat will be thrown into your a2w rad which will heat it up.

seriously i commend your idea and it work, but not to the best it can because your rads need to be swapped around.

You mention putting 2 rads in, that wont help much as chris mentions, as you will cool the IAT with the first rad, but ypu have used that air which heats up, it then gets sent through the car rad, which again heats it up further then you put it through your second a2w which warms that water inside it.

thats why i thick your better swapping your rads around that adding another

 

Yea I def agree that radiator behind and in front should make a good difference but since I already have it there might as well get some numbers first. What I will do is run some tests this way, just to have some numbers for anyone and for people doing it in the future and then I'll put the same rad up front and compare the difference (hopefully all on the same day so the humidity and temp stays the same). Then when I have numbers from those two I'll try even a bigger a2w radiator up front to see if it helps even more.

 

haha ChrisRX8PR I know I hate the headlights just as much as you lol, but the onces I like are $400 or $500 so those are gonna have to wait a lil

 

I consistently see 20 C above ambient. While and air to water heat exchanger is an interesting idea, I don't see it being practical using a small closed loop system. Even supercharged waverunners with an infinite supply of cool lake water struggle to keep IATs down.

 

You know I actually had an AIT sensor installed on my stock fd b4 the engine blew a few yrs back but I can't remember what my temps were. Anyways though, much props for the A2W conversion. I love seeing creative threads like this done on a budget. How's the throttle response now with the shorter piping?

 

Always was curious about a2w good to see one on an fd

 

Stock FC intecooler is very small (its only 12" x 6" x 3" = 216ci) and my a2w IC core is 450ci, not to mention that water absorbs heat way better then air obviously because of the density difference between the two. 20 degrees C over ambient is hard even with a pretty good size front mount. Your gauge maybe inaccurate or have a very slow response time. Also keep in mind you need to record the temp when your car is at normal operating temp and under full boost for sometime.

TB response is awesome, from full vacuum to full boost seems to take less then a sec. I almost hate how much power my car has, it spins tires all through 1st, and 4k rpm through redline in 2 second gear. Stock FD piping isn't long btw, but it is very very restrictive. It creates a LOT of turbulence and that's what kills the response time

I love doing one of a kind custom stuff like this, I mainly did it just for fun :-). I just took my taillights apart to make them look like 99 spec but I messed one up. Left it in the oven too long

 

Have you loaded it up with heat yet?

 

Looks good. It will be nice when you have some data about the performance. There have been a few A2W & Chargecooler setups done in the past, but no real data associated with them. Looks like you have everything setup to get some data so I'm looking forward to when you can get it out on the road.