Craig Mack

Hey guys! Me and Tom are ready to build me up something to cool my air charge. He says aftercooler because its less piping. There is a reservior that makes the water, and I'm sure you guys know how it works, theres no "filling up" like you would on an aquamist setup. But some of yall say a FMIC is better. Why? I'm heading up there now to install my FPR but wanna take your guys' advice on which one to do.

With the AEM FPR back on (hopefully this one wont be a dud), the S-AFC, tuning, and intercooler, I'm hoping to pick up in the neighborhood of 60fwhp. Is that unrealistic? This is humid florida, so mind you im losing more power then most of you guys.

Thanks for the advice...

ejj

iTrader: (5)

Personally, I'm leaning towards a FMIC right now. Seems to be a simpler option.

I really don't think the piping would be _that_ hard, and I've got someone that knows what they're doing to help me. I may pick up a simple welder and see if I could do it myself (maybe followed by exhaust).

But, I change my mind all the time!

DA-MAX

iTrader: (10)

IMO AWIC = more worries...pump failure, leaks no thanks, somewhat convenient fitment though. FMIC seems easier and probably will cost less.

Stephen Max

iTrader: (59)

Sorry, I can't help you Craig, I'm still undecided. I'm leaning toward a FMIC, though. I really like the way a FMIC looks from the front. I usually try not to be influenced by looks over substance, but in this case I may make an exception.

If you went to the track a lot I'd say to go with the AWIC for the ice-bath option.

Craig Mack

Guys,

First off, we are talking about an Air-to-liquid FMIC vs. an Air-to-liquid Side mount intercooler. Sorry if my wording was a little f'ed up. Is everyone still on the same page?

The front mount intercooler is more piping then a side mount intercooler, right? It is Tom's opinion that the side mount cooler will be LESS piping, and therefore give better gains. We looked through Turbonetics magazine, and we picked out a $600 core that is AWESOME. Its like, 4.5 x 9 x 12.5L, Superior coolage and flow. Total price for the entire kit would be ~$1200 installed and powdercoated to a pretty blue. $1200 is for all parts and labor installed.

What do you guys think? Is it worth the price? I'm looking for 30-40whp rich in the power band, not just peak power. Anyone have any estimates on power I will see boosting ~9.5lbs.? I also just figured out that Tom won't even do a FMIC, only a side mount, because the FMIC is more work, more $$, and more restriction then a side mount AWIC anyways.

LatinMax

iTrader: (1)

I have benn kind of asking the same type of question.

Stephen Max

iTrader: (59)

Eh? You lost me there, Craig. Side mount like what the 300ZX TT has? Where would you put a side-mount AWIC in a Maxima?

Craig Mack

My bad. I am a newbie at this stuff. What exactly is a side mount? The one im talking about sits where the battery is. Here, check this out for the type of cores I am looking at. (mines not listed). http://www.turboneticsinc.com/liquid.html

ejj

iTrader: (5)

FMIC = Front mount Air-to-Air intercooler
AWIC = Air-to-Water intercooler.

FMIC's are more piping, and usually therefor more work. However, once installed they are no-maintenance.

AWIC's use a water tank, water pump and heat exchanger (radiator) to cool the charge.

AWIC's are cool because you can put ice water in them and get the air going into the engine COLDER than the outside air. FMIC's will only get the air as cold as the outside temp (or close to it).

I've been looking at the piping involved for a FMIC, and I don't think it would be all that tough. Out of the SC you'd take a 90* down, then 90* towards the front of the car, 90* towards the drivers side and into the IC, out of the IC, 90* to the back of the car, 90* up, then onto the MAF and so on (if you can picture than, then congrats).

Side mount like your turbo tom guy wants to do is ok. But its going to limit you to a smaller core and get less airflow. There's no better spot for airflow than right in the front of the car...that's why the radiator is there.

DA-MAX

iTrader: (10)

when you said sidemount this is what I thought...


my SMIC from a 1st gen Eclipse(mounted in the fender)

AllGo

iTrader: (1)

First of all a side mount i/c would be to small. I did a good deal of research spoke with one of the best i/c builders out there. If you look up spearco intercoolers on ebay and see the seller boostcoolers this is who I talked with about my plans. He said even with a very efficient bar/plate core with dimensions like 7"x8"x4.5" a side mount would be to restrictive and not cool effectively by not supporting enough cfm for the boost the s/c generates especially when you can't just turn up the boost like a turbo to overcome this.
The awic is a good idea say with a good PWR barrel mounted where the crossover piping would be or maybe a good spearco awic core and putting a good jabso pump/reservoir in the batteries location and a good exchanger/radiator out front. The complexity of this seems to great however the idea of running ice at the track poses some tuning issues with such a cold charge as opposed to the standard operating temp of the regular awic setup.
A front mount air/air would be the best as opposed to the awic. I was s/c for the first half of the year putting down 326fwhp and 270tq with stock injectors. I was looking to do a fmic to gain 40hp/tq across the power curve. I already had a big hole in my passenger fenderwell to run the outlet of the s/c piping towards the front bumper area. From the perspective of looking at the engine bay you could run a good 90 silicone coupler right of the compressor outlet at about 7 o'clock into the fenderwell, then a 120 or 90 towards the bumper and you are halfway there with a good fmic setup. I also had a cai at one time so getting back to the intake and maf would be simple as well. Keep in mind from what I learned that you will need at least a core of 8"x 3"x 18" to get enough flow with minimal boost loss, like 0.5psi. And as far as turns in the piping, these will not restrict flow at all.
One thing to consider is that if you are maxing out the injectors now, where will you be with a cooler charge and better torque?

Craig Mack

Hmm....if water has 4 times the cooling capacity of air, why in the world would an air-to-air FMIC be better then an AWIC? And with a front mount, wont the core be MUCH thinner? The side mount cores come really fat. So wouldnt that make up for the flow? And then again, the fact that its cooled by water and not only air...I'm not seein' how thats not a much better option?

Chunger

iTrader: (1)

AWIC has advantages and disadvantages... It (water) has a much better thermal stability and so it can carry off more heat but keep in mind that you need 2 heat exchange systems (Ambient Air to Water then the Water to Charged Air) in an AWIC vs. FMIC. Although water can take away more heat, there needs to be a temperature differential for it to happen and also water pumps. Hence, using ice water you can get the charged air lower than ambient air. Only an advantage at a track where you can dump in ice just before the run.

AllGo

iTrader: (1)

If you want to put together a good awic system, it can be done, but with that said it would require good attention to detail when concerning the heat exchanger/core/pump setup, but the piping would be a breeze.

As someone here stated before once you build a fmic there is no maintenence and you will still see temps within probably 15 degrees of ambient, but again a colder charge can be seen with ice and a awic. I think a good fmic setup with couplings/clamps, intercooler, and piping could be done for around $650 which is hard to beat. $350-400 for the i/c from boostcoolers, $100-150 for approx 4 mandrel pieces, and the rest for couplers and clamps.

I still say a side mount is to restrictive even with an efficient core and
bottom to top flow or top to bottom flow. The surface contact and cfm will not support the hp #'s you/others are looking for. The intercooler builder I spoke with basically said he would only use a side mount with a turbo since turning up the boost could overcome the bottleneck. Still even the good side mounted factory turbo cars almost alway upgrade to a fmic because of its performance.

Stephen Max

iTrader: (59)

If you're talking steady state efficiency, then an air to air FMIC is more efficient than an AWIC because there is only one heat exchange process involved. With an AWIC, you have two heat exchanges happening. The charge air is cooled by the water, and the water is cooled by ambient air. The problem is that the water always remains warmer than the ambient air, so the charge air is being cooled with a medium that is warmer than the ambient air, whereas with an air to air system the cooling medium is at ambient temperature. It is true that water can absorb a lot more heat than air, but you can never get the charge air lower than the cooling medium. The increased heat capacity of water just means you can get by with a smaller heat exchanger.

In a transient situation (which is really what most of us are concerned with), then other things come into play. When you do a stoplight to stoplight run (on private property, of course) most of the charge air heat is absorbed by the mass of aluminum in a FMIC and by the water in a AWIC. There is not enough time elapsed to get into steady state heat transfer and the intercoolers act almost entirely as heat sinks. Most of the heat (by far!) pulled from the charge air and absorbed by an intercooler is rejected to ambient air after the race is over.

The ability of a material to absorb heat is dependent on its specific heat. It turns out that water has a specific heat that is about 4 times greater than aluminum. That means that pound for pound, water can absorb four times as much heat than aluminum per degree of temperature rise.

So in a transient situation where a massive amount of heat is being dumped into either a FMIC or a AWIC over a short period of time (let's say 13 seconds), and both the FMIC and the AWIC start out at an initial temperature slightly above ambient, and the weight of the aluminum FMIC is equal to the total weight of the AWIC including the water, then more heat will be pulled out of the charge air into the AWIC than into a FMIC and an AWIC is more effective. Of course if you start the AWIC initial temperature at less than ambient by using an ice bath, you come out way ahead.

Craig Mack

So, with all the mumbo jumbo aside, which do you guys think will yeild more power? I'm talking daily use, not special ice baths at the track.

ejj

iTrader: (5)

I think a Front mount air-to-air intercooler would be the best for everyday use.

DA-MAX

iTrader: (10)

FMIC + 6 more characters

Stephen Max

iTrader: (59)

Sheeesh!!! Mumbo jumbo??? Why do I even bother...

Craig Mack

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Craig Mack

Steve, you know your loved man. In fact, im going to forward lots of this info about the piping, efficiency, and core for a FMIC to Tom. Thanks to you guys I have changed his mind, and he is willing to do a Front mount.

FMIC = No maitnence, and produces more usable power then a AWIC do to the bigger core.

AWIC = Lots of potential maintnence, small core limits power, (in turn will make less daily than an FMIC), but you can do "ice baths" for the track. Which I don't care about.

Thanks a TON guys, especially my freezer geezers Stephen and Ejj, and Allgo.

Allgo, should I go with an 8"x 3"x 18" core, or bigger? Also, can you provide a site or something where one could be ordered? I'm afraid they will start getting to be like $600-800 just for a nice core.

ejj

iTrader: (5)

.

Stephen Max

iTrader: (59)

Freezer geezer??? Come here you whippersnapper, I'll whack you good with my cane!!!

Actually, I gave some reasons why an AWIC is better than a FMIC for situations where you are operating in an unsustained boost mode, i.e. street fighting from stoplight to stoplight. For sustained boost (such as NASCAR type racing) it's better to have a FMIC.

Nevertheless, you're probably better off with a FMIC due to its simplicity.

Craig Mack

So, you think an AWIC would be better UNDER the boost curve? Why is this? How much better would it be? If were only talking several HP here, then IMO who cares. But I really want more low end power, and if an AWIC reigns supreme on that, then....

Craig Mack

Then again, I also need a lot more power in 5th gear @3000rpm on the highway. And I usually always gun it from a roll anyways, the question is, how fast do you need to be going before the FMIC starts to take effect.

SSR Engineering

Intercooler definitely, theres alot of potential use for it rather then some cheap aftercooler. Aftercoolers are useful if you live in a cool climate, other wise they are just going to be as hot as your coolant is. Since they are cooled down by your coolant. A custom intercooler with CO2 spray would be the ultimate thing to do.

DA-MAX

iTrader: (10)

ummmm....cheap aftercooler?? do you have any idea what you are talking about an efficient aftercooler setup is no where near being "cheap" but its usage in daily driving situations isn't optimal. many top drag imports use aftercooler/AWIC setups...with the ice bath combo it can't really be beat...and aftercoolers DON'T have to just use coolant...most setups use a seperate water tank and pump, the water is then cooled via a small oil cooler type radiator(some even use small AC condensers) placed toward the front of the car where cool air will contact it. I agree w/ you that the FMIC/CO2(or N20) sprayer would be a nice street setup, but your other facts aren't all true.

SSR Engineering

Well lets speak more cost to efficiency. Cheap aftercooler meaning Vortech style, not something you have to shell out tons of cash for something as minimal as cooling charge air. FMIC is alot more practical hands down.

Stephen Max

iTrader: (59)

There are people that use the engine coolant to cool the charge air?

ejj

iTrader: (5)

I would imagine you'd have to use 50% anti-freeze in the winter so the water doesn't freeze, but I couldn't see why you'd use the actcual coolant that cools the engine.

Stephen Max

iTrader: (59)

Indeed. First of all, you're making much more engine heat when boosting, which the coolant has to carry away, then you're going to add the charge air heat on top of that? Sounds like a recipe for disaster.

ejj

iTrader: (5)

Yup. I'm hoping he was just refering to using some anti-freeze when he said 'Coolant'. Not the engine's coolant itself.

Craig Mack

Do FMIC's provide power UNDER the boost curve?? (3000rpm and below)

nismology

iTrader: (8)

W/e or not you see boost with a supercharger is more dependant on throttle application than RPM.

DA-MAX

iTrader: (10)

lost of good AWIC info and pics here---->

http://www.honda-tech.com/zerothread?id=436872

ejj

iTrader: (5)

Minimal if any. Neither setup would help much at that low RPM.

Stephen Max

iTrader: (59)

I agree, but I would like to add: The supercharger gets pretty hot because of the engine oil use to lubricate it and also because there is a heat conduction path from the engine to the SC through the mount. So the intake air is getting heated up a certain amount just due to passing through a hot blower even if it is not being significantly compressed. So if an intercooler (of any type) can remove some of that heat then it should, theoretically, increase power even at low rpm. But like you say, the gains are probably minimal. I'm sure Craig can come up with an exact number.

Craig Mack

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Max4Speed

iTrader: (20)

I guess its time for me to order that too. I will stop by over the weekend to getsome more info on this.

IceY2K1

iTrader: (3)

AWIC like Vortechs' aftercooler will cause less lag due to shorter piping lengths. However, depending on how long you are boosting, the efficiency will decrease as the cooling water is warmed to the point that you're limited by the size of the water/air heat exchanger, which is typically pretty small compared to a FMIC. So, once the water gets hot, you're no longer as efficient as a FMIC.

FMIC will cause more lag then a AWIC due to pressure drop caused by the additional piping length, which IS a concern when you are boost limited by a pulley size, but not as much of a concern with a turbo.

Unless someone has or will R&D a AWIC, I don't think you'll see the benefits over a FMIC.

Check here for some "tips" I've compiled from different magazines I collect:
http://forums.maxima.org/showthread.php?t=249681