With an intercooler on a turbo charger, one way to use nitrous, one would do a nitrous shot on the intercooler, when the throttle is wide open. Giving you a performance boost. Even though nitrous is far colder than propane being at -88c and propane at -40c. Now, would be able to use a propane shot to cool your intercooler instead of using nitrous. This would be a far cheaper alternative. But, would the off gas of using enough propane to get the job done be hazardous? And how much would one have to use to make it work? I have a top mount intercooler in my Subaru and it being in the engine bay doesn’t sound like it would work well, but it still might. Front mount would be most ideal for this.
Does anyone think this would work or would one go boomboom
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Liquid to liquid intercooler and dry ice 
Are you trying to get your intake air temps down to add boost at the track? Road or drag?
Could work well. It all depends on what you want to do… Small amounts of nitrous all the way down the track works great on a turbo car to just keep the IATs down
Just get as big of an intercooler as you can fit with a good quality spearco or similar core with interfoilers inside the fins that cause turbulence and help a lot with efficiency.
Or just convert to E85 or propane and not worry much about the IATs because of the octane
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Well, here it gets so damn hot that my subi gets so pissed off and runs like absolute crap. I had the idea that if I were to chill my intercooler and cool down my turbo. She’d run far better. And then I could turn it up to go wee bit faster when I wanted. Fortunately it’s cooling down and she’s running far better. But, I still have the idea to give it a whirl
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Is it modified much? Id be worried about a shoddy tune. 100+ degree days can sure make your car slower but around town it shouldnt be a huge issue.
im curious if you have some other issue. Any CELs?
If you get ping on a turbo motor under boost you can kiss it goodbye real quick.
What kind of running like crap are we talking about here?
Maybe you just need a tune up?
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She’s pretty new. It’s when it’s over 110. She tries to spool up too early and has a problem getting out of 1st with the ac on when it’s that hot, too. Wrx do not like the extreme heat and slow city driving.
And she’s dead stock. Only has a problem when it’s hot. I take her in to the dealership every scheduled time for maintenance
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Have you googled the problem? If its common youll get a ton of info.
The Subaru message boards would be a great place with people experienced in that particular motor / platform and their workarounds / fixes.
Heat compounds problems so it could be something as simple as the ECU going into low timing mode for the heat (most likely) or something like a bad spark plug that can take your shit out.
Im used to old school aftermarket fuel injection controllers without knock detection and other options. These days cars have a lot of failsafes so they dont just turn into a paperweight when a turbo motor looses a throttle signal or something simple
Honestly I think it should turn the boost down to combat the heat or have a dumb down mode for reasons like this. But they really just hate the heat with stop and go traffic
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Maybe look into keeping the scoop mounted intercooler and add a large but thin intercooler in front. Cant go wrong with surface area for cooling.
You should get an OBD2 scanner and an app like Torque. You can watch your IATs in graph form and get lots of other useful info.
Its my go-to if things arent quite running right or will tell you if you left something unplugged that doesnt trigger the CEL. Plus you can graph fun things like boost and get instant MPG readouts
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I’m still more interested in using propane instead of nitrous.
That’s more the concern.
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It sounds like a bad idea. At least around here the smell alone of a constant spray of propane would have everyones mother in law calling with your license plate #
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I have built a few classic subarus up to 700 WHP , built for time attack.
The top mount inter cooler on the classics are useless, you should change it for a front mount.
As for temperature and running, I would advise like @Luckycat said. Take it to a reputable tuner in the area where you live and have them remap the ECU.
The shot of nitrous / propane will do nothing for your situation.
You would have to constantly run gas through the intercooler to get your charge temp down to what the ecu is happy with.
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Sounds like the logical fix is a much larger turbo, fuel pump, larger injectors and front mount along with a tune
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First !!! Motec ecu, Oil temp sensor, oil pressure sensor, fuel pressure sensor, A/F ratio sensor.
Then do what @Luckycat said lol.
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Or we find an intercooler that will fit in a Pyrex
Ive been thinking about starting a car thread and seeing how many of us car nerds are around on here. I suspect a lot.
About dred’s problem. Im curious, ill prob do a google search and see if everyone has this issue at high temps
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I work on cars but dont drive. I’m into bikes… ( and broken bones ) lolo
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I’m stupid … It just dawned on me, you could fill your wind screen washer fluid bottle 70/30 ethanol water.
Get some double sided tape and some wind screen washer jets.
Stick them infront of your top mount and plumb them to the washer pump ??
Any good to you ? Its something that was done on the RA and 22B if i remember correctly.
Would be alot less savage than a bottle of propane in the passenger seat with a tube and regulator hanging out the window haha.
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I drive a mazdaspeed 3. Been working on it for sometime now. Been having a struggle when WOT in all gears. Broke a fuel pump, replaced that, and put a larger internal in the new pump to keep up with the stage 3 pack on the car and it’s still sputtering.
Finally figured out its the fuel filter. Got super dirty from sitting for a year. New filter tomorrow and all the WOT power should be back. 
Car guys unite!
Propane sounds scary. Why not just put dry ice near your air intake? Or if you have a filter box, in there?
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Why take it to a tuning shop? I have a warranty until 100k miles that covers everything but the clutch, glass, and tires (basically). I’m not even halfway there. You’re overlooking what I am actually wanting.
I don’t plan on putting any upgrades on it. That’s not my intent. I drive like maniac enough as it is. In Arizona it is regularly well over 110. Subaru especially with a boxer motor are notorious for overheating here for no reason. Couple mine being a wrx with a turbo that hates it when it’s far above its comfortable operating temperature.
Now that happening, caused me to have an idea of using propane instead of nitrous to cool the intercooler.
The car problem just made me think of it. Key point.
It’s not hot here currently and I’m not having the same problem. It’s far from my first Subaru, nor my first, or second with a turbo.
Propane is far cheaper and I can get it non odorized for rather cheap from my solvent supplier. In theory, would it work vs nitrous.
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But you can’t put dry ice on the intercooler whenever I want.
With that in mind, ln2 is really cheap
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10lbs every day. Lol
Just set a block up in the hood scoop
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