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Okay, first question, is it bad to get the intercooler too cold for drag runs as long as the engine is at operating temperature?

Second question, if I were to make something to put over the intercooler...a block of ice I strap down or something, would this be better than the air going over the intercooler? Since I was blocking the air would it not be good, or would it be okay since htere's a block of ice melting all over the intercooler?
 

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Can't get the intercooler too cold with regular ice. Dry ice on the other hand might not be the best thing to lay on there. But I'm not sure.

You *NEED* airflow through the intercooler fins. You want to ice the intercooler BEFORE your run, and take the ice off before you make your pass.

Truth be told, even in this humid/hot climate that I run in (Hawaii) icing the intercooler hasn't ever made a difference for me. :(
 

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A block of ice would be terrible. No air flow that way. You have to expose EVERY little metal fin to air, and a big 'ole block of ice would only be in contact with a small percentage of the fins.

Now shaved ice, stuff that melts in a hurry would be great for a cooldown between runs, think dumping snow on the TMIC, just make sure it melts. I don't know how the TMIC handles thermal shock tho...might wanna hear that from a pro.
 

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I went through and did some science experiments on this.

The intercooler works like a heat sink - it is made out of aluminium which is a very good conductor of heat. It takes in air that can be over 100 degrees Celcius and some of that heat is transferred to the metal of the intercooler -so long as the intercooler is at a temperature cooler than the incoming air.

THe amount of heat transferred is also influenced by the difference in temperature between the incoming air and the intercooler metal. And the amount of time spent in the intercooler (this doesn't change much, but it is a short amount of time)

If your intercooler metal is at a temperature of 40C there is no way that you can get your intake charge temps below 40C and it is also very difficult to even approach that temp because the temp difference is so small.

Now here is the important bit. Metal holds a lot of heat. Even good conductors of heat like aluminium can hold a lot of heat and take a lot to cool them down (think about how long it takes for the engine to cool).

IF the intercooler is at underhood temps right before you go for a drag run - there is no way it is going to drop very much in the 12-14 seconds it is taking to get to the other end of the strip. If the intercooler is at underhood temps - your intake charge is not going to get anywhere near that temp - it is going to be higher.

I have a temp sensor between the throttle body and the intake manifold that measures the charge temp. In the middle of summer in traffic or a staging lane - this temp can soar to 60 or 70 degrees C!!!! It takes about two minutes at highway speeds to drop that temp to around 35C when the outside air is around 30C.

So what does this mean?

Your intercooler has to be cold BEFORE the drag run - the amount of cooling you are going to get from the 12-14 seconds worth of air coming through the hood scoop is not going to do much for you.

I would not say - go use a huge block of ice because that is not the most efficient way of cooling your intercooler - and it would probably bend the fins! But completely covering the intercooler in a 1" layer of ice is not a problem.

And here is the reason. Water is a great cooler!! Think about a frypan that you have just cooked something in. How long would it take you to cool that down by blowing on it???? Long time right. How long will it take to cool it down by running it under a cold tap? About 10 secs??? Water is like metal - holds a lot of heat - and can soak up a lot of heat.

The ice on your intercooler gets to 0C and then soaks up a fair bit of heat to change state to a liquid - at which time you have water at 0C that then drips through the intercooler fins - taking more heat with it and dropping out the bottom.

Using this method - I was able to reduce my intake charge temps into the 10-20C range whilst idling and not moving. (Staging lanes I hear you cry!!)

Here is the problem - you take that ice off and don't have air flowing over the intercooler - the temp heads back for the 60-70C in about a minute!

The flip side is leave the ice on there - but most drag strips have a hernia if your vehicle is leaking/dripping. You have to judge the amount that will finish melting just as you get to the start - or stop the drips getting out the bottom!! A lot will evaporate on the transmission.

So - I agree with brembo in that the single block of ice is not a great idea, but for a different reason - the airflow through the hood scoop during a drag run is like pissing in the wind - not gonna do you any good. Get that intercooler cold before you start.

I never got around to part 2 of my experiments which were to use dry ice instead of ice - solves the dripping problem!!

Cheers,

Andrew
 

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Aussie-

Actually, I was hitting at the same point. I mentioned the fact that the block will only hit a small percentage of the cooling fins. Ya need to get cold water down in there(shaved ice/snow kinda stuff). Water can absorb 333 joules of energy per cc(before vaporizing). Air is much less, MUCH less. So, water across the IC is the best option, even dry ice will have inferior cooling properties in comparison to water. But like you said the heat soak is quick, and by your numbers, icing the system doesn't help much.
 

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Well, air isn't the best conductor of heat, as a matter of fact, its one of the worst... that's why its such a great insulator. But other than that, instead of using ice, why don't u just water it down with really COLD liquid water. If I recall correctly, liquid water's specific heat is 1 cal/C'g (or 4.184 joules) while solid water's specific heat is .49cal/C'g. I don't think it is worth the time to use the ice. Just spray the intercooler with water. In that way, it would easily get everywhere on the intercooler.
 

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What I was thinking - but didn't get around to proving was that dry ice, whilst not quite the energy sink that water is, it is starting at -76C rather than maybe -18C for ice straight out of the freezer.

It would also solve the dripping problem!!
 

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BurnOutz said:
Well, air isn't the best conductor of heat, as a matter of fact, its one of the worst... that's why its such a great insulator. But other than that, instead of using ice, why don't u just water it down with really COLD liquid water. If I recall correctly, liquid water's specific heat is 1 cal/C'g (or 4.184 joules) while solid water's specific heat is .49cal/C'g. I don't think it is worth the time to use the ice. Just spray the intercooler with water. In that way, it would easily get everywhere on the intercooler.
The problem is keeping the water there for long enough to do the job - you pour a gallon of water over the intercooler and see how long it stays there - very short term solution and as I said - the heat soak occurs very quickly.

Intercooler sprays are most effective, not from the water directly on the intercooler, but from the fact that the fine spray cools the incoming hood scoop air (ie when moving) and that cooler air more efficiently cools the intercooler.

Cheers,

Andrew
 

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First off, I know nothing about this, but have been wondering that if the i/c is chilled too cool on a humid day, could water start to condense from the air inside the i/c? It would be working sort of like a de-humidifier. Of course, the next question ... what effect would that water have on the engine intake? Not good I would guess. Just wondering since in sounds like some are willing to go to extremes with cooling.
 

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Anyone knows about N-Tercooler Kits??
Are Nitrous Kits to spray in the IC.
Isnt that a good way to gain HP at the Drag strip?
Thanks
TUca
 

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tuca33 said:
Anyone knows about N-Tercooler Kits??
Are Nitrous Kits to spray in the IC.
Isnt that a good way to gain HP at the Drag strip?

I was reading up on that system also... (NX website)
Im Gonna Try to Mock a Similar system with C02..
C02 Is much cheaper and more safe...
the only Nitrous kit I would use would be the one that actually goes into your engine. (NEVER HAPPEN) :p
 

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Icing helps

Icing helps but you need to get it done before you get to the line.

I agree 100% with the heat sink concept.

I have a thermometer on my IC and monitor the temp of the intercooler. I can ice it down to about 45 deg F before a run, and the IC temp as I roll through the timers booth is about 65 deg F on a day with 95 deg F outside temp.

Here's what I do.

After a run, pull into the parking lot and get the hood up quickly to let things cool.

Buy a small garden sprayer and fill it with just water. mist down the top of the IC, the intake manifold ( focus on the coolent tank bolted to the passenger side )
and spray the radiator a bit.

Do this for a few minutes until the water on the intake manifold no longer evaporates in a matter of seconds.

Place two large double hands full of ice cubes in a towel, pull up the corners so it forms a small bag and whack it on the pavement a few times. Presto instant chipped ice.

Place the ice on the fins of the IC and mist a little water over it to get some cold water running down into the IC fins. Now cover the top with the towel and go back to spraying the various hot spots on the engine.

When the ice is just about melted, do another double handful of ice and put it on the IC, cover it with a towel (you want no air flow through the IC at this time so all cooling goes into the metal) and quickly start the car and move to staging.

This takes a little timing but at my strip this batch of ice will be all melted just before I get to the end of the staging line. When you get to the point your about 5 -6 cars away from staging, pull out the towel and any remaining ice, close the hood and your ready to go.

The last couple times you move the car toward staging use a jerky braking motion to be sure all water has come off the IC and engine so your not dripping water.

Your IC should be about 45 -50 deg if it is in the low 90s F using this sequence as you pull into the staging lights.

Larry
 

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I've tried it at the track, but with less than spectacular results. My best time was without using it. Of course it will help, but my results were not dramatic.

And hotrod: A garden sprayer is what we always used on our cars (mostly V8 muscle cars). They work very well.

My favorite thing to use at the track is an empty sprayer bottle. I fill it with water and drop some ice cubes in it. I get out of my car occasionally in the staging lanes and spray my intercooler down. I tell people it's my intercooler sprayer mod :D Most get a kick out of it, some just think I'm stupid. ;)

VV
 

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I use the spray bottles too

Yep!!
I keep a spray bottle in the car, hang it on the arm rest of the passenger side door.

It keeps you occupied when some moron oils down the lanes.


A little spray on the ice cubes really accelerates the cooling. I use that to burn up the last bit of ice rather than to throw it on the ground.

Larry
 

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Well, on the topic of icing the intercooler:


Courtesy of PlatinumWRX :D
 

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hmm...

hey, im not totally sure about what is inside an intercooler. But isnt it just fins? so if your put water or ice onto it, would that risk dripping right into the throttle body? just a quick question that i pondsered, lemme know what the deal is. thanks
 

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Re: hmm...

caz5511 said:
hey, im not totally sure about what is inside an intercooler. But isnt it just fins? so if your put water or ice onto it, would that risk dripping right into the throttle body? just a quick question that i pondsered, lemme know what the deal is. thanks
no tube and fins.
 

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just built my own i/c sprayer this past w/e, cost me about $35, mounted the water tank behind the passenger side foglight, water stays real cold and sprayer works excelent, will post pics of my own in this forum in a day or so, forget co2 and n2o water is the way to go and uhhhhh its free...:wiggles:
 

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and dont forget in a situation like that you could always put ice cubes in your ic water sprayer tank and be spraying water thats 32 F on the ic. thats what i plan to do when it really matters...
o-|-<) bryan
 
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