Thread: water to air intercooler set up

Hi all,

I need a little help with the water to air intercooler i plan to use on my GTI-R.
I am ready to put the engine back in the car. It is a fully forged engine, 2260cc running on a GT35 turbo. I decided to go for a water to air intercooler for reduced lag, constant air temps and efficiency.
The kit is based on a PWR barrel 6x10 intercooler, a very large heat exchanger with a 600x300x40mm core and a Meziere water pump with AN12 lines.
The idea was to use a 2 gallons water tank in the engine bay. The problem is that the engine bay is already full of items and that 2 gallons is not that much volume.
So the best option would be to put a larger tank in the boot of approx 3 gallons.
My only concern is about the water pump and its flow capabilities.
I plan to feed the pump just after the tank, but because of the increased hose lenght, i am afraid the the water flow will loose some "force" and will travel slovly in the radiator and in the chargecooler and back to the tank.
Should I stick to my original plan of a tank in the engine bay?
Or the flow should't be a problem? Or should I consider the fitment of a second pump? and in this case, should I run I run pumps inline? or the second pump should be fitted before the inercooler?
the GTI-R is already front heavy, so putting the tank in the boot is a better idea and will also give me more room for the air filter?
Any suggestion is higly appreciated!

You won't need 2 gallons of coolant for an air/water with a large enough heat exchanger. No reservoir should be needed as long as your heat exchanger is of sufficient size.

For what it's worth, I will be changing to my a/w setup shortly. It will just consist of a decent heat exchanger, a cheap straight through intercooler core, and a pump. We'll see how it works. I guess if you ran a reservoir you wouldn't really need the heat exchanger as much. 2 gallons takes a while to heat up on these setups.

Depends on what you are doing. Drag racing it is ok and you don't need a large heat exchanger. Any road courses, autox, tt, etc... It isn't enough... you have to have the large heat exchanger. The extra water volume doesn't keep it any cooler.

Right, what I am saying. There is no point to have both. If you had a small heat exchanger, then the larger capacity would be good. There is no point in having 2 gallons of water and a huge heat exchanger.

A lot of the coolers I have seen are way overkill also. You don't need a radiator-sized heat exchanger.

Have you ever tracked a w-a setup? The radiator-sized heat exchanger is needed... Trust me. I have one and it barely keeps up on a hot day with alot of runs.

Like we both are saying 2 gallons and large exchanger isn't needed. If he is building drag car... 2 gallon with no heat exchanger. If he is building street/strip car I would say medium sized exchanger with small resevoir. If track car then large exchanger with little to no resevoir.

Dude, I run a 5 gallon tank in the trunk with a Jabsco pump and 1/2" lines. The more water, the less heat soak and issue. I daily drive and track the car though so it is a help. I run a 10x10x1.25 exchanger with a spearco core 5x5x10 W2A IC with my 5 gallon cell in the back.

Brent

If you can't get rid of the heat fast enough at the track (road course) it doesn't matter how much water you carry.


There is math behind thermodynamics... With more water volume it takes more energy to raise the temperature of the water... Very true, but... The size of the exchanger determines the temperature that the water will stablize and reach homeostasis at. So with your larger water capacity it will take you longer to reach your homeostasis temperature. But on a road course(s) I have seen a 3 gallon tank in my miata reach temperature in less than 2 laps. 5 would of course take longer, but wouldn't overcome session. I traded weight of volume for larger heat exchanger. I reach homeostasis quickly, but it stays cooler (compared to larger resevoir with smaller exchanger) and never goes up for length of runs.

a 10x10x1.25 core isn't that big. I would go with something like this:

Air to Water Radiator

A cooler this size should be good enough for just about everything (no reservoir) except the sluttiest of track sluts.

Use this one if you seem to somehow overpower the one above.

Air to Water Heat Exchanger

I have used this one on my friend's G20 and even in 110* heat, beating on the track, the IC NEVER got even lukewarm. It stayed cold with a GT25 heaving 16psi of boost through it all day long. With no reservoir. I wouldn't hesitate to say that coolant temps never got over 120*, even in the 110* heat.

I plan on running a 24x7x2 core and I don't expect to ever have issues with it. I don't track the car a whole lot, but it gets occasional track days and a lot of DD abuse.

I actually can't wait to use my A/W on my car. All of my friends have had really great results.

The system is based on a water radiator with a core size of 600x300x40mm, which is as big as I could go. It is basically the same size of the large intercooler usually found on ebay.

Water to air system are often built around smaller radiators and still work very well, so I think that my set up will work very good, but I still believe that a water tank can only further improve overall performance.

My car is not a drag car, it will be used on the road and occasionally on track. I will put a reservoir as large as possible.

Again it would be better to fit it in the engine bay so the pump will be able to flow better.

I read somewhere that the tank should be placed higher than the chargecooler, is that true? Cause in any case I won’t be able to o that.