chinewalker

What size heat exchanger are you using and where are you placing it? Ive heard of guys using small radiators from motorcycles, but im thinking i should have one almost as large surface area wise as large A2A intercooler.

TIA

digital sol

iTrader: (1)

I am running a 28x8x3. It was made to those size spec's, honestly haven't finished my build yet but im shooting for 500+whp. Really depends on your goals and the function of the car.

1) What power cooler are you running?
2) What is your WHP goal?
3) This a dd, drag car, or autocross setup etc?
4) Power level goal?

I went overboard on my setup sense I will also be driving it heavily on the weekends and when weather permits during the week. I wanted something reliable enough to DD and not run into issues on those hot summer days. I went with a larger front mount heat exchanger, PWR barrel intercooler, 5 Gallon water cell & a meizer pump. If memory serves the pump should move around 20gpm. Probably over kill but in the future I shouldn't have to re-do any of it anytime soon..."was the plan anyways".

Frozenboost.com has a wide selection

sp00led

http://pwrusainc.com/intercoolers.as...its&id=26&sp=8

I've got one of these on my turbo s2000. The radiator is smaller than a civic half sized radiator. Looks more like the same size as the stock one on my Raptor 660R ATV or GSXR750 bike.

chinewalker

Im using a genaric barrel style cooler with a ford lightning pump and a 3 gallon cell.

Shooting for 400whp

Daily driver that will see alot of track time

wantboost

iTrader: (2)

the problem with most motorcycle radiators, at least with most sport bikes is that they are curved to fit the space available

most people overlook that an a2w system needs to be pressurized to get the best cooling benefits, just like an engine cooling system. make sure you get a heat exchanger with a pressurized, radiator style cap

also, don't use antifreeze, it doesn't transfer heat well in this application, use distilled water and water wetter (only in weather above freezing) and be sure you have a high flow capacity pump.

Alfa Turbo

Pressurized, really? Not so.

While water wetter and water will be most efficient for heat transfer, using antifreeze is more user friendly if you live anywhere it freezes and the delta T is not that different.

chinewalker

Pressurized? ahah the water is never going to get hot enough to need that. I live in Canada also so ill be using antifreeze.

The bosch pump i have flows 317gpm and is designed for car intercoolers. There are cheaper marine pumps made for baitwells that flow over 500gpm and they are fairly cheap, but i cannot find out what king of pressure they can make. I not sure which pump will actually flow the most once it is hooked up and has to push water through all the lines, core and exhanger.

wantboost

iTrader: (2)

most turbo cars see outlet temps in the 200+ range, hot enough to make the water in the cooling circuit boil.

tepid1

I think you're units of flow are off. To move 500gpm were talking 3" hose at 50psi kinda numbers.

The Bosch Ford Lightning pump flows 317GPH. FYI

tepid1

Depending on the compression, it's actually common to see turbo discharge temps in the 450+ deg F range. With that being said, the key to a good a2w setup is flow and capacity. You hint to pressurization, while it's not a bad thing (pressurization raises boiling point in a fluid), in this case I would recommend an expansion tank. The benefits of having a system with no air outweighs that of pressurization.

In fact, antifreeze may be a good thing if you are putting serious heat into the core.... The glycol raises the boiling point even further past pressurized water.

At work, every day, we run our plant at 2200psi and water temp is 575 deg F. Still plenty of margin to prevent localized boiling. The key to controlling localized boiling is flow. You need to move the heat and allow the exchanger to do its job.

Alfa Turbo

If you are getting anywhere close to 200*F I submit your system is poorly engineered.

I run a 400WHP motor. I see IAT temps at +26*F over ambient after an hours heavy use.

So... if it's 80* outside and I drive hard for a while my IAT's are 106*, and that's after a while. Less than 30 minutes I see 10* or so over. That's at idle or full boost.

I run about 2.5 gallons total capacity of 50/50 and NO Watter Wetter. I use a Mayfair Marine Proline bilge pump which is 500GPH. They last about 3 years and cost $25.00 with shipping. It mounts to a custom made CF tank I mount in the rear and run hoses to the front. It runs continuously when the engine is running. It's designed to drain back to the tank on shutdown so water does not get heated in the engine compartment. Another reason not to pressurize. Were I to make a design change I would modify the tank so I could easily drop a load of ice in it and have sub ambient temps for a while.

Water takes longer to heat up so it takes longer to cool down. One point I think many people miss is that off boost (your are not on boost ALL-THE-TIME) the inter-cooler is also a heat exchanger, it cools the water too.

I run an 6" x 10" (I think) oil cooler as the main heat exchanger it mounts in front of the AC condenser.

The easiest way to improve efficiency is not by increasing the size the heat exchanger (which is often times difficult from a packaging point of view), just double the flow with a pump that flows more! Make a system twice as big or cycle the water twice as much.

YMMV

wantboost

iTrader: (2)

yea I was thinking that for a space limited street app that a pressurized system would aid in controlling fluid dynamics where you can't run a large expansion tank (your setup should be an example followed by all wanting to go a2w, especially that anti-sweat coating)

because street cars can't really run a large expansion tank, especially not underhood... I know some relocate the battery to the trunk and run a 3 gallon tank in place of the OEM battery, whether it be fuel cell or expansion tank.

some run them from the trunk (obviously) but there you can get away with a smaller capacity tank because the sheer length of the feed and return lines accounts for a good volume of liquid, of course longer line lengths requires a very stout pump

I found an electric pump at PRI last December from Craig Davies that I think will replace not only mechanical water pumps but any cooling circuit where a high volume, high precision pump (with numerous control strategies)

I'll post a link if they have the product online now, if not I'll scan my document on their various models.

Alfa, I would love to see your CF tank (always love seeing awesome thinking executed in unique ways) I'm also curious as to.how the system would drain back, given the length and routing of the lines

Tepid, for an average 400-500hp street car, what size expansion tank would you suggest? I'm still debating about running an a2w setup for my gt2871r setup, just for the sake of keeping IATs constant and predictable. I might even try a small compound setup (yea yea, totally experimental lol) and would a2w intercool each stage.

but really I think with my gt2871r ls/vtec setup that a2w would be far more consistent in terms of IATs and would allow me to eliminate at least half to 2/3 of the ic piping I would've needed for an air to air, although I do have a very nice PWR intercooler thats perfect for my setup.

the hardest thing I forsee with going air to water is finding the appropriate intercooler unit, properly sized heat exchanger (huge isn't always the best unless you're cheating to get extra fluid volume in the system lol) and then sizing an appropriate expansion/ice tank as well as a pump and adequately sized lines that are routed as best as possible (my biggest fear would be a line failure with the lines running through the cabin)

plus the trunk clutter, for me it would be something like this... battery box, water/meth tank, a2w tank, fuel system swirl pot, etc. so you have to figure out how to package the entire thing so it makes sense

tepid, you can pm if you want or I'll pm you

chinewalker

Youre right, i meant gph not gpm

Alfa Turbo

I copied the Romans and use gravity!

How are you going to pressurize your system? If you are planning to use heat why do you want IAT's over 212*F? Just stay A2A and you will get better performance.

One more question... what happens when a pressurized system gets a leak in the intercooler after you shut down and water, under pressure, gets in the intake?

tepid1

I agree. With that cute little turbo, I wouldn't waste my time with a2w. Keep it air2air and have fun. KISS.

Water injection!

wantboost

iTrader: (2)

I'm not saying I'd have IATs that high, the turbo outlet temps will be in the 200-300 degree range, pre intercooler. with a non pressurized a2w setup you would have to be able to move a great volume of water through the core to prevent the water from spot boiling due to the amount of the water would absorb. the expansion tank would help prevent this because as it's name suggests, when water enters the tank it expands, bleeding off most off the heat it absorbed, the heat exchanger furthers this cooling effect but there's only so much that a system can do in terms of absorbing heat and not boiling, no matter how much fluid you pump through the system.

why do you think engine cooling systems are pressurized? even.with coolant temps in the 180-190 range that's hot enough for the coolant to start outgassing and producing air bubbles. pressurizing the system prevents this and forces any air out of the system.

I've seen a lot of high hp domestics using pressurized a2w systems because they generate enough heat to boil the cooling liquid in the core faster than you can pump water through it. also the likelyhood of a core developing a leak is very minute, assuming the core and welds are of good quality, you'll never have an issue unless the turbo ingests something or the turbo itself fails and punctures the core

just exploring other options, even though I'm only using a 2871r, I'll be using it at its limit. add in hard road course driving and I don't think even my PWR air to air core (with puller fans for cooldown and to maintain airflow during slow course sections/cautions) will be able to keep IATs at a reasonable level, especially on hot days and the fact that most of the air passing through the core will be heated air coming off the track surface.

the a2w setup should produce consistent IATs if I can move enough fluid through the system, have a properly sized core, as well as a properly sized heat exchanger and am able to draw enough air through it.. because the courses we run on regularly very seldom allow for driving out of boost, with the exception of slowing and braking for corners. I'll heat soak an air to air system fairly quick.

I'm about to put my gt3582 on my dd f22a1 accord, that should yield some interesting results but I think my other PWR air to air core should suffice.

I'm only really concerned about managing IATs on my civic when I'm at AMP, Road Atlanta, or Barber (and trying to chase down our 600hp z06 and countless R35s) I will still street drive the car but I'm not worried about IATs in that situation.

Tony the Tiger

I just want to elaborate more on actual running experience with A2W setups. I've been running it on my Evo 9 for 2 years now, which sees street, track, highway and top speeds (I do full throttle pulls up to a minute long continuous), winter driving and long trips. In fact, all my cars go through the same type of driving, but I just choose what to drive whenever...LOL

This car isn't really fast compared to my other cars, based on its power to weight and AWD hindering the highway speeds, so it does get subjected to a lot of "boosting time". The engine and turbo setup is working hard to haul this heavy car with a puny 2.0L.

Anyway, aside from some of the points already brought up, here is some info from what I've gathered.

The A2W setup on my Evo consists of:

- 1000HP Garrett Core, custom end tanks (1.5" deep, half round with 1/2" NPT water ports)
- FrozenBoost 26" x 7" x 3.5" Heat Exchanger, mounted where stock FMIC used to be
- 7" fan for heat exchanger, with manual switch
- Bosch Water Pump with 5/8" lines. Lines are short, no longer than 4 feet for each hose
- External reservoir, holds about 1.5 L, vented cap (not pressurized)
- Total System capacity of 2.5-2.75 L
- 40% Coolant / 60% Water with Water Wetter (does well enough for winter too)
- Prosport Dual Ch. Pre- and Post- Intercooler IAT gauge, + stock IAT pre-turbo for ambient air
- Less than 1 feet of piping length in total

There must be a purpose to run A2W. My goals were to improve boost response in which the Evo can surely use more of, to run the smallest compressor and turbine possible to reach my goal of 550-600WHP, to help frontal air flow for cooling to the radiator by eliminating the stock taller FMIC which blocks half the radiator near the front grill, and to ensure cool intercooled air starting off 1st gear when there is almost no air flow to a traditional air-to-air FMIC.

The Garrett core has literally no pressure drop, and it scored some "slack" on my GTX3076R turbo so I was able to push this turbo past 500WHP with no concerns of knock, with 94 oct. I was able to get a GT30-like spool off the line, and for this power level, it was worth the extra effort for an A2W.

Boost response was much better, especially between shifts; not just WOT gear to gear shifts in a straight line pull, but even when I short shifted to enter a corner or if the corner required me to upshift early. Regular daily driving shifts are also quicker to recover, and I can hear my turbo spool up and down effortlessly at lower RPM's.
The only disappointment was, it did not really improve my RPM vs spool time, only the response factor of it and its ability to maintain spool. I still spool up on the dyno like a typical GT30R Evo on stock motor and mild cams.

The car no longer feels sluggish from heatsoak after sitting in heavy traffic... Once I was free from traffic mayhem, my first pull of the lights in a gap of traffic felt just as good as every pull. For a Honda, you may have to consider whether this is a good or bad thing. I didn't want this for my Integra because if I were to just pull off the line in 1st gear with full power, it would spin with cold tires. I like my Honda to have more power as I progress into each and every gear, which an air-to-air becomes much more suitable.

There are no real drawbacks except for cost, complexity to build the A2W, and to fit all the essentials to run this system. The only problem I had, was that the stock ECU + ECUFlash had trouble coping with the A2W, due to the huge piping length difference and the car being originally MAF. My fueling/time was way off, and the ECUFlash had no method to alter this enough to make it run properly. I had to bump up to a Haltech to sucessfully run it.

As a reference, my post-IC temps were always within 30 deg F of ambient. I sampled it on a load-brake dyno, pegging the throttle at 7000RPM at full boost for about 10 seconds to make sure I am getting true airflow reading that can saturate the sensor itself to give a steady-state like reading. Probably due to my oversized system, the air temps were always within range under all conditions even when I have little airflow at the front heat exhanger (dyno testing condition).




Fan Setup (Dual 7" shown, but worked better with single 7" in the middle):

Alfa Turbo

Since you showed me yours Tony, I will show you mine!

This engine uses factory ITB's making the intake a little different.

I am glad to see you report IAT's at no more than +30*F ambient. Like I posted above I see no more than 26*F and when I share that just about nobody believes me, or they say it spikes under boost. As you know IAT's stay table top flat.

I went this route mainly for packaging. I don't have space for an A2A intercooler and I wanted to keep the AC condenser.

FWIW it's a GT3071R .63. This spring I plan to play with pre-turbo water injection. I want to simulate the turbo response I get in cooler/cold weather when it's 80+F outside. I can't be the only one that loves cold weather driving a turbo!

wantboost

iTrader: (2)

oh my god, I love that model alpha lol.

both of your setups are well thought out, brilliantly executed, and aesthetically pleasing to the eye (most setups look like a cluster **** of lines going everywhere, intercooler in the most random of places, people using windshield fluid tanks for an expansion tank, etc

these are two of the most sanitary air to water setups I've ever seen... and I've seen a lot

I had planned to do something similar if I went a2w for my 2871r build

Alfa, I would still love to see your tank and line routing. I'm curious as to how your setup uses gravity given the different install heights of various components and the line routing to and from your cf tank.

wantboost

iTrader: (2)

Alfa, I also like how well you incorporated your cooler into the intake plenum, since I spy a set of itbs under the core

D-Rob

I've been dealing with A2W systems a lot over the past couple years with the supercharged K-Series guys.

Ice is always a fun thing to add to those systems!

spoolinlude

I had a PWR A2W with my old setup. Bigger heat exchanger is definitely better, and make sure it gets LOTS of air flow.

I used a 5 gallon fuel cell as an expansion tank, way overkill, but it worked.

Mine was too small, and ended up being the demise of my engine. Spiked the IAT's on the dyno, detonated, that was the end.

I did learn a couple things though:

- Get the largest heat exchanger you can find
- Keep all the lines as short as possible
- Get plenty of air flow to your exchanger, much like a A2A setup needs
- Get 2x the pump you thought you needed

I kinda miss the 'sleeper' look I had, but A2A is much less complicated, and works quite well.

digital sol

iTrader: (1)

Pro's & con's of short vs longer lines?

Ive made sure my setup is overkill but curious about the lines as I chose to run my lines from the trunk thus, short lines is anything but existent. I went with a way overkill pump "1200gph" to compensate but just curious. The pump is mounted in the trunk as well right next to the water cell. I was hoping with an overkill pump, pressure/flow through the system all though long would not be an issue.

tepid1

FYI, that 1200gph pump after going through 20ft of hose isn't 1200gph anymore. There is a lot of hose resistance (surface area decreases flow).

I hope you're running large lines....

wantboost

iTrader: (2)

longer hpses means the pump has to work harder to move fluid from point a to point b, this means a significant reduction in system pressure and system flow. flow is more important as you have to move lots of fluid through the intercooler core, tank, and heat exchanger to keep IATs in check

thus if you have long lines you need a pretty serious pump to keep the a2w system operating under nominal conditions vs a system with shorter lines.