intercooler, air or water?

[Lith]

lets get back to the original question here.....

Hey, he asked for advantages and disadvantages - what best way to give them than by debate?

[Mr Revhead]

how can we advise if we dont know the application?
as i reckon that determines the advantages/disadvantages

[catchafox]

what is the best way to switch a w2a i/c so its not on all the time and only switches wheen needed?

[sergei]

get one of those electronic thermo switch kits from jaycar (more expensive one) and hook it up to water pump, and install sensor in the hottest part of the i/c (just next to inlet elbow - somewhere in BOV area on ST205 i/c). That is if you are good with soldering iron and not affraid of electrics.
Or get one of those slim fans on the i/c radiator and hook the thermo switch to the fan, while turn on the water pump all the time.
I have the second option, the inlet temperature is below 40'C even if it is in traffic, or boosting most of the time (spirited drive). I run CT20b with overboost problem (soon will be fixed) - @ ~20-26psi.

[hsmidy]

hey cheers guys for all ya info, its for a 20b in my ta22, want to keep it looking standard from the outside so yeah would much rather go w2a, costly but seems better over all

[Mr Revhead]

well i dont think itll cost any more than a flash a2a

[Boosted_162]

Now, im in this same predicament at the moment. Im not sure on which cooler i want to use. This is in my ST185. Final power goal will be 400ish hp, but not for quite a while. I already have a ST205 water-to-air, and a RC bumper. The only cons i see of this setup is i need an RC bonnet (is that bad?), and theres a bit more setup to do HOWEVER i can do this myself, but i cant really with a FMIC. From what i can think of, the pros of a w2a far outweigh the pros of a a2a (in my case). Less lag, and less heatsoak (3SGTEs get very hot under the bonnet).

What does everyone else think?

[Stealer Of Souls]

Personally I agree with your assessment...
Given the choice, and given the normal use for a vehicle, I think W2A is the winner.
If it was a track toy, or race car, A2A, no competition.
But a street car. W2A.

[Boosted_162]

Alright, sounds good.. I would want to do some racing in it, but thats not entirely what its for. I want to drive it to the track, through some twisties and just enjoy it. The only downside is the cost of an RC bonnet

[Malcolm]

You don't need an RC bonnet to fit a w/a intercooler in a celica

[Boosted_162]

The ST205 one must be bigger then. I removed that rubber shroud, the bonnet will close but its slightly higher on the sides (doesnt line up with the guards). Did it fit fine under other bonnets? I think it might be catching on the cam cover pipe if it can actually sit lower.

EDIT: Ahhh correct as usual Malcolm . Bonnet does close, but its a tight fit!!

Oh and where did you get your RC bonnet from anyway?? I wanna get one now anyway

[Adoom]

My experience with std subaru w2a on THE STARVIA!!! OH YEH!!
Street: is sweet as. There is enough water to soak up heat from the random short fangs you do. And enough time between fangs to cool the water back down.
Track: not so good. Fanging it all the time, so either you need alot of water to soak up all that heat or a really BIG radiator to cool that HOT water back down fast enough. I had issues cause it kept boiling all the water away!!!!!
I gave up, and got a VR4 fmic for $60. No looking back.
I could have made the w2a work but I would have had to have a decent sized water tank and a radiator bigger than my fmic is now. I didnt have room for either.

OH yeh. Docile makes loads of power and only uses a w2a because it only needs to keep cool for 10seconds at a time. Not for laps and laps and laps.
w2a is good for drag racing because it can make the compressed inlet air colder that the ambient air temp. especially it you put a shit load of ice in it (But only until its soaked up enough heat from the air to warm the water) but drags are short as so the water never gets hot.

a2a doesnt get the inlet air as cold but it will do it forever.

I'm not saying don't use w2a on the track but be prepared to carry the extra weight of a decent size water tank and a radiator almost as big as your engines radiator.

a2a = EASY!!!

Get the idea?

GO THE STARVIA!!! OH YEH!!!!

[Boosted_162]

I really cant make up my mind on which one to go for. I have plenty of room for a big radiator, but im sure theres quite a bit of cost in that. And a big downfall of the w2a is, i have to remove the whole tank and drain the water to get to the plugs and leads, not something i wanna do often! Plus im sure id have to upgrade to a fmic once it gets inefficient (it will ALWAYS be a project for more power, never finished ) Then theres the added looks of a FMIC..

[Adoom]

I really cant make up my mind on which one to go for. I have plenty of room for a big radiator, but im sure theres quite a bit of cost in that. And a big downfall of the w2a is, i have to remove the whole tank and drain the water to get to the plugs and leads, not something i wanna do often! Plus im sure id have to upgrade to a fmic once it gets inefficient (it will ALWAYS be a project for more power, never finished ) Then theres the added looks of a FMIC..

Use longish water pipes to the w2a and run them so that you can undo the clips for the IC pipes and move the w2a out of the way without taking off the water hoses. Downfall <= nil.
Radiator cheap as. You go to wrecker and get suitable sized radiator with copper end tanks. $20?
You go to radiator shop or plumber friend and braze on smaller pipes(3/4" I think) to take the size hose you use on the w2a. $40ish per pipe change from the guy I used. Bear in mind it will block air flow to the engine radiator.....so if thats marginal it will be worse.

For the water pump, the easiest place to get one is from RS legacys.(PICK a Part) If it doesnt flow enough water for you, GET TWO!!!

You dont need to buy new everything when second hand stuff is cheap and it works.
My EFI ful pump was $12 from pick a part when I run out of flow I'm not going to get a $300 new one. WTF4? I'll just get a second $12 one and run it in parallel.

Who wants looks?? Go stealth, and eat cars that think they are the shiz.
Thats why my car is fun. It looks slow as, and none of the panels are the same colour It must have looked funny as when I was (legally on a closed road ) racing an XR6T and keeping up.....I've got more power since then

[matt dunn]

How come ATA is better at high speeds?


We have ATA in the focus and even at 240 KMH we see averagely high inlet temps on the motec logging,


Saw the same engine setup last week with a PWR WTA intercooler and there logged inlet temps were all at least 20 deg c below ours.

I would have never though that WTA could be that good but they were still tuning and up to 400hpish, and still that far below us in temps.

[Boosted_162]

At night i dream of a PWR water-to-air

So, i will get good results using the ST205 heat exchanger up top, a bigger radiator up front (maybe put a fan on it?) and run the pump constantly. I already have a subaru radiator and pump, might try and get the RC radiator tho as its bigger i think.

Sound like a plan?

[sergei]

WTA physically increases possible working area of the heat exchanger.
With ATA you are limited to intercooler size - as going too large has negative effect on the performance. With the WTA the air to water side can stay relatively small (as the water can take away heat very efficiently - due to higher heat capacity). But you can increase the water to air substantially, also design of the heat exchanger can be more efficient - because internal drag, turbulence and other properties are not important - the water pump will push it anyway, while the Air to Air intercooler internal design has to be "unrestrictive", unrestrict air flow = decrease cooling efficiency of the cooler.

I use air cooled car vs water cooled car as my argument example (as you see a lot more water cooled cars than air cooled on the road) . Watercooling leads to more consistent results.

[sergei]

On the subaru radiator -> I use ST205 intercooler with CT20b (Steel) and subaru intercooler radiator with 10" fan on it. The car makes about 180kw @ 16psi atw, the inlet temperature before throttle will never go above 40'C under boost. I had a temp sensor in there for a while. Only seen ~60'C after heat soaking while not running (engine stopped after good run and sat for about 15min), but once the ignition is on the temp goes to slightly above ambient very quickly (couple of min).