AWIC questions

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James614
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AWIC questions

Post by James614 »

Does anyone here know if there's a functional difference between the black and silver Legacy/Liberty AWIC cores? I know that when it comes to Air/Air slanty TMICs, the blacks are usually standard WRX and the silvers are usually higher-flowing STI units. Does this hold true for the AWIC cores also?

Also, has anyone here tried their hand at fitting a water core from Frozenboost.com/Siliconintakes.com? (Type 13 maybe?) They're about the same price I've seen the Subaru AWIC cores go for, so if one of these is just as easy to install as a Subaru unit I might just go with that. But I'm REALLY preferential to the Subaru cores because they basically complete our engine bay and look slick vs. a mysterious aluminum box... I don't go for the aftermarket engine bay look, especially something like that which is pretty much front & center and shiny as you open the hood. I'd have to spray it black or something so it at least isn't the first thing you notice when you open the hood.

On a side note, if anyone knows of a Suby AWIC core for sale, don't hesitate to hook a brother up ;)
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dscoobydoo
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Re: AWIC questions

Post by dscoobydoo »

As far as we know, there is no functional difference in the early AWIC Subaru cores. Some of the RS ones had a sensor in the top, but since the sensor will not work with the existing ECU/ car, it is a pointless feature.

Check ebay and NASIOC for the upper reservoirs. They come up every now and then.

Realize that your VF-11 will not work with the AWIC core, so if you are going this route, you might want to consider a turbo upgrade at the time to at least a TD04 off a WRX.

Check out my posts on my AWIC car.
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James614
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Re: AWIC questions

Post by James614 »

Thanks. I've been watching here/NASIOC/eBay for a bit now, I'll probably spend a while waiting. I wanted to know in case there was a difference, if I should risk waiting months longer to find a specific type. But if nobody knows then I'll just grab the first one in good shape that comes up :) ... whenever that may be.

I'm aware of the VF-11's crooked outlet, which is why I'm also keeping a keen eye out for a TD04 or preferably a VF-10/TD04 with the 90* inlet. With the matching turbo, the install should go fairly smooth... *crosses fingers*
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Re: AWIC questions

Post by James614 »

Yay! Finally found myself a JDM AWIC core :D :-D For the record, for those who have yet to feel one in person, these are some hefty units! From pics I always thought they were made of some thin tin/aluminum, an assumption encouraged by numerous damaged units I've seen for sale. But these mofos are heavy-duty and thick as hell, I can't believe how well built it is. How someone would manage to do more than scratch it is beyond me, unless you use it as a wheel chock or a shooting target or something ridiculous.

Now to find myself a pump & heat exchanger. Pump I'm not to worried about, there's dozens of decent OEM Bosch pumps floating around for good prices. And the pump can easily be upgraded with no changes to the system when the time comes, it seems.

But I'm debating what to do about heat exchangers... my first choice is the Frozenboost.com Type 100 because it's almost as large as the A/C condenser and will hide nicely without that street racer FMIC look. But it has really tiny end tanks and puny 1/2" fittings. I can't imagine it flowing very well despite it's generous core size.

So I'm thinking about small car radiators, possibly Honda/Suzuki/Geo 1.6L or smaller. They ought to work great for an AWIC application I'm thinking.
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Re: AWIC questions

Post by gijonas »

I think flow with the heat exchanger is not the biggest factor to consider.You actually want the coolant to Hang out for a while in the exchanger.Heat isnt exchanged to air instantly,it takes some time.And you probably dont need an exchanger the size of a radiator,large heater cores and motorcycle rads are common.
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James614
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Re: AWIC questions

Post by James614 »

Good point about flow through the exchanger, I had kinda gotten myself wrapped around the idea that biggest w/ fastest flow possible will be best. But it makes sense that past a certain point you just have water whisking by before it has a chance to absorb/release the heat. Although in the end I doubt it could be worse, there's certainly a point of diminishing returns. It probably won't hurt me to settle for something easy and cost-effective as long as it's good quality.

And I'm not building an STI-eating monster, this is just a stock EJ22T with a slushbox :lol: The AWIC is just to provide reliable support for future mods that I won't have to go-back and re-do as I make more power. So it's probably silly for me to build a system capable of cooling a 30psi monster.
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evolutionmovement
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Re: AWIC questions

Post by evolutionmovement »

There might be calculators online that can get you in the ball park for area and flow rate.
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Re: AWIC questions

Post by James614 »

I'm thinking I'll just err on the side of too big for area, since larger radiators/heat exchangers don't really cost much if any more, and it'll give me desired safe room for future upgrades.

Flow rate is the big q?, but looking at other people's setups I should be safe just getting an OEM Bosch pump, their flow rate is better than the stock Subaru but not outrageous like Josh's Jabsco pump (and much cheaper). With a large area exchanger I should be able to dissipate all the heat I need without a fancy constant-diameter low-pressure-drop system. If future mods make too much heat, I know pumps are out there that flow 5x more than the Bosch ones, and the only people I've read about not liking AWICs are the ones running crappy stock pumps and heat exchangers anyways (gremlins, install headaches, and PITA problems not withstanding) :P

My quest right now is finding out what will fit off the used market... mostly car/motorcycle radiators, since people don't generally seem to want to sell their AWIC heat exchangers second hand. And I can't ignore the fact that I can get a radiator for $100 less than the cost of a new large-area heat exchanger.
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Re: AWIC questions

Post by Legacy777 »

I'd definitely suggest going with as big of an exchanger that you can fit. 1/2" fittings are ok, but can be a little restrictive. The thing you need to remember is that the pump flow rates are rated at a given pump "head" or backpressure. The more backpressure in the system, the lower the flow rate. In most cases you will probably flow 1/4-1/2 less than what the pump is rated. If you have a very restrictive system, the flow could be decreased further. The only way to really know is to test it. The easiest way is to do kind of what I did with the 5 gal. buckets and a stop watch.

The stock AWIC core hose is very close to 5/8" ID hose. If possible, I'd suggest running that size hose. It's large enough where it's not too restrictive, but is still a managable size.
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James614
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Re: AWIC questions

Post by James614 »

Oh hellz yeah! I just snapped off a nipple on my coolant reservoir. I'm part of the cool club now!

And now I have excuses to drive my wife's Escort everyday, because driving a turbo Subaru was getting boring.

.... :evil:
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
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Re: AWIC questions

Post by James614 »

I was thinking about going with a Ford SVT Cobra/lightning heat exchanger, but word from Cobra/Lightning owners is that they suck balls for anything more than a quick stab at the gas. But then again, these are big supercharged V8s pushing 400+ ft-lbs, so I don't know how their heat output compares with a turbo four. But they have larger outlets and end tanks than most aftermarket units, and their size is about the same as similar shaped aftermarket ones.

I'm still leaning for something tall and thin, similar to the A/C condenser. I'm sure they cool much more effectively than the short and thick ones, despite almost identical core area.
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
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