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Discussion Starter · #1 ·
Hey guys,

I am working on developing an air to water intercooler that would bolt on in the place of the stock TMIC.

Advantages:

1. Cooling better than a FMIC, much better than TMIC
2. Stealth factor. Radiator in front smaller than a FMIC and not shinny "look at me" polished.
3. Great throttle response just like the stock TMIC, no lag increase like you get from a FMIC setup.

Disadvantage:

1. More complex than either FMIC or upgraded TMIC. Water pump, radiator, reservoir, and the core itself.

2. Heavier than a TMIC due to weight of the water... not sure in comparison to FMIC with all the extra piping needed for a FMIC.

A FMIC upgrade cost anywhere from $850 to $1500 depending on brand and Vendor.
An upgraded TMIC cost anywhere from $800 to $1000

I want to do this for my own car, and I am looking into the costs of production. Simply put if it is less than the high end of the FMIC range I will go for it.... what about everyone else?

How much would it be worth to have a bolt in system that gives cooler air going into the engine than a FMIC and the throttle response of a TMIC?

Keith McDonnell

PS: If there is already a bolt in air to water system out there, point it out and save me the pain and suffering of developing one of my own!
 

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I think air to water coolers are an older thing. I've seen some that used the same cooling circuit as the engine. My thoughs are that this is going to be less efficient and way too complicated. Water is much more effective at cooling than air though. So try it and let us know what happens.
 

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Discussion Starter · #7 ·
jwtarbaj said:
Well the fact that every automaker I know of is using Air to Air ICs in their current or recent (last 5 years) vehicles that I know of says to me that Air to Water is not the way to go.
And we all know that automakers always do what is best for performance rather than doing what saves them money right?

With an air to water system you have a pump, and the potential for leaks. In an air to air system there are zero moving parts, and there is no water side that could over time develope a leak. That means that as well as being slightly cheaper to build in the first place due to not needing a fluid pump, there are damn near zero warrenty claims on an air to air intercooler system. If you sell thousands of vehicles you will have a certain percentage that have a fluid pump failure or hose failure during the life of the cars warrenty, and that costs the automaker money.

Automakers work on the "good enough" principle. Could they have put the STi intercooler in all of the regular WRX's for slightly better cooling of the air charge? Yes! Why didn't they then? Because the one we have is "good enough" and slightly cheaper to build than the STi intercooler.

Will an upgraded top mount air to air intercooler give you better cooling than the stocker with throttle response that matches the stock top mounted air to air intercooler? Yes.

Will a front mounted air to air intercooler give you better cooling than any air to air TMIC but give you worse throttle response? Yes.

Will an air to water intercooler give you better cooling than any TMIC (compaerable to a huge FMIC) along with the great throttle response of an air to air top mount? YES!

One of the best trucks in the world (GMC Syclone/Typhoon) used an air to water intercooler from the factory.

Keith
 

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I think it would be a sweet idea. Most of the really fast guys use them. I don't see the need for one in my car, but if I were to get crazy with it, you bet this is something that I would be looking into.

Keep us posted Keith, this sounds great.
 

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The original RS Liberty used an air/water IC. Back when Subaru was designing the WRX for the base car for the WRC, Prodrive tested air/air vs air/water ICs. They discovered that with a water sprayer, air/air ICs were equally efficient, more reliable, less complicated, and lighter. Also maintence free.

Sorry I had to be the antagnoist.
 

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Vew said:
The original RS Liberty used an air/water IC. Back when Subaru was designing the WRX for the base car for the WRC, Prodrive tested air/air vs air/water ICs. They discovered that with a water sprayer, air/air ICs were equally efficient, more reliable, less complicated, and lighter. Also maintence free.

Sorry I had to be the antagnoist.
Add to that the fact you could spray CO2 or NO2 on the IC and further increase the efficiency and it says not worth the time and effort. Talk about heat soak when that liquid gets heated underhood.

I also have to say if GM is one of only 2 manufacturers using air to water it takes a step down in my book. They aren't exactly on top of the technology world when it comes to engines. (Please don't spout how great the Vette motor is becaue for 7 liters 505 hp is not super impressive 72 hp/L decent but not world class)
 

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Sorry, the vette is world class, and air to water intercoolers are just different, not better or worse. GM uses them because they are slim under roots style blowers, and cool very well with the surface area they have. They have their applications, but routing huge air hoses everywhere is not the best way to do things in my book, having the intercooler right next to the intake, and just small water lines seems better to me. Top mount is fine for the small hp of the wrx, but any of us straightliners know, sitting in the lanes with the heat just baking that thing, makes you want to smash it to pieces. Different strokes for different folks.
 

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Discussion Starter · #13 ·
Exactly!

I am not against anyone who wants to get an upgraded TMIC, or FMIC. I am just saying that anyone in a situation where they are thinking of a FMIC they can get the same cooling with an air to water setup and not loose the throttle response of having a TMIC. You loose the "bling" of having a big shinny FMIC though, and that is an important thing for some people..... like mxboy said, different strokes.

Keith
 

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mxboy15u said:
Sorry, the vette is world class, and air to water intercoolers are just different, not better or worse. GM uses them because they are slim under roots style blowers, and cool very well with the surface area they have. They have their applications, but routing huge air hoses everywhere is not the best way to do things in my book, having the intercooler right next to the intake, and just small water lines seems better to me. Top mount is fine for the small hp of the wrx, but any of us straightliners know, sitting in the lanes with the heat just baking that thing, makes you want to smash it to pieces. Different strokes for different folks.
I didn't say the Vette was not great I said the engine technology is NOT. Geez noone has any reading comprehension anymore.
 

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The engine technology of the vette is showstopping. It makes tons of power and torque over a very wide range, weighs just 100 lbs more than a rx7 rotary, and will last forever. Nothing compares to the new vettes in my opinion. Read about that motor, maybe you will learn something. This whole "high tech/low tech" thing stinks of honda. Last time I checked no civic was winning races with hp per liter. It really comes down to hp, torque, power curve and weight. The z06 motor or even the LS2 has all these features, and backs it up.

Back on topic, when cars making 400+ hp are using air-->water, that says something as far as daily driving efficiency and cooling capability.
 

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turboshelbys said:
subaru has already made one. this unit can from a 90 b5 legacy. i will be running tests to see what difference there is between the air/water vs. air/air stocker.
Well I'll be damned.....I wander why they didn't put these on the mid 90's turbo legacy's...they choose to go with out an intercooler at all..
 
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