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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Intercooler on NA
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Fri, 21 June 2002 06:50
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Yep, another crazy idea from me.
We know the job of an intercooler. Would it make any difference on a NA engine? Does it require a turbo to push the air through or is it unrestrictive? Would it bog down throttle response?
If that is all good, then that should be better than a CAI.
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Location:
Newcastle
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 07:28
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i would say it would stuff up the throttle response but also may have bugger all effect. if you have a look at your throttle body it may have coolant hoses going to it. you may ask why do they want to keep this hot? it is so that the air flowing over the throttle body doesnt condense and freeze to the throttle body and induce water into the engine.
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 07:32
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Your idea needs more work...
Remember what an intercooler does? It cools compressed air back down to a temperature closer (but never equal to or lower than) ambient. It needs to do this in force fed applications because the act of compressing air also releases heat.
If you don't compress the air it will be at ambient anyway so an intercooler will do nothing but add restriction to your intake.
don't do it.
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 07:34
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cold air ducting wil serve more of a benifit.
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 07:35
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Ok cool. Trash crazy idea.
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Location:
Newcastle
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 07:38
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i know what would be good to go with the intercooler. A supercharger. imagine your camry just hauling off from the lights with the supercharger whining and the intercooler sittin out the front
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 07:41
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Yea, but how much is a supercharger? I don't think there are any charger kits for the 5sfe anyway are there? I know there is a turbo kit, but I dunno about a charger.
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Location:
Brisbane / Gold Coast
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 10:55
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FWIW, some of the Five Litre Touring Cars use dry ice in the inlet system to cool the air before it goes into the engine during the qualifying runs.
Reason why an intercooler won't work with a n/a engine - An intecooler will only transfer heat back to ambient air if there's a temperature difference. If you're just using an intercooler before or after the throttle, then there's no difference so no cooling.
Anotehr reason is that with an n/a engine if the ambient air temp goes up by 10° then you only notice a small decrease in performance.
A rough guess with a turbo engine is that for every 1°C increase in ambient temperature, you'll get at least 5°C increase in air temp after the turbo compressor. So that 10°C soon becomes a good 50°C, and that really starts to hurt!
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Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 13:18
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instead of running the air through an intercooler, why not modify the air con and put the AC radiator on top of the air box. that should cool things down!!
Tim.
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 13:22
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Thanks Bill.
| RA28 wrote on Fri, 21 June 2002 11:18 PM |
instead of running the air through an intercooler, why not modify the air con and put the AC radiator on top of the air box. that should cool things down!!
Tim.
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I want an aircon. 
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Toymods member
I supported Toymods
Location:
Rydalmere, NSW
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 14:02
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| Apollo wrote on Fri, 21 June 2002 5:41 PM |
Yea, but how much is a supercharger? I don't think there are any charger kits for the 5sfe anyway are there? I know there is a turbo kit, but I dunno about a charger.
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Go do a search on any good search engine for CASA or Superchargers (I can't think of the site address), but they've assured me there that they can 'make up' just about any supercharger kits for just about ANY N/A engine.
I think it's worth hunting around for... how much you wanna spend on a supercharger kit?
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 15:34
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Hey, no worries, just have a word with stealthi1. Not sure if I've seen him on the new forums, but his stories of wasting HSVs and the like in his supercharged camry on the old forums entertained me for hours.
I believe he worked for one of the major supercharger manufacturers, so would deffinately be the man to talk to.
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Location:
Finland
Registered:
June 2002
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Re: Intercooler on NA
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Fri, 21 June 2002 20:05
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on a naturally aspirated engine under bonnet temperature is the foe. that's why 'cool air ducting' shows improvement.
if my memory serves me right, every 4 degree raise in inlet air temp will knock off power by 1%.
this problem is clearly present on older engines where inlet- and exhaust manifolds are on the same side of the engine. isolating exh manifold (thus reducing radiated heat) will pay off.
paying attention to improving enginebay ventilation will help to gain back some lost hp. not really something one should loose sleep over. weekend track racer however will however benefit from this.
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Sat, 22 June 2002 00:15
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I've got no problems with the actual intake. That's why I'm not really caring about a CAI.
The engine is a e-w configuration and mostly sits on the right hand side of the bay. The air intake is on the other side infront of the battery. I think standard, it's pretty good. Also there is a heat shield on the exhaust manifold.
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Location:
Brisbane / Gold Coast
Registered:
May 2002
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Re: Intercooler on NA
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Sat, 22 June 2002 04:55
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No Message Body
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Registered:
May 2002
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Re: Intercooler on NA
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Sat, 22 June 2002 10:04
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Nascars (and many other race cars) use fuel coolers. Not unlike an oil cooler the fuel travels through before the injectors. I have seen them used on some fuel injected street cars/v8's (one in particular that's bloody scary, NA - over 1300 ft-pounds of torque, cause thats all the dyno read to) and they definitely work!
The other "cooling" used on the intake of NA engines somethimes is manifold insulators, where the manifold and the head have a spacer plate made of a low thermal conuctive material to keep the inlet manifold cooler.
And, to correct a commonly misquoted fact, an intercooler CAN cool below ambient. Why? Because its moving and the ambient air stiking it as the car moves can cool the intercooler below ambient.
But jeez, to do it it has to be a big, efficient intercooler to dissapate that amount of heat.
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Location:
Newcastle
Registered:
May 2002
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Re: Intercooler on NA
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Sat, 22 June 2002 12:59
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in regards to the fuel cooling a lot of motors actually try not to cool the fuel but even heat it up a bit. as the heating of the fuel helps atomisation and therefore also helps an even burn pattern in the combustion chamber.
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 06:27
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Unless the air goes through an expansion (which it doesn't really) it is physically impossible for the intake air to be cooler than ambient.
Its a basic law of thermodynamics. Flow of air past the intercooler can never drop the surface temperature of the intercooler to below ambient.
If simple forward movement allowed you to cool things below ambient wouldn't airconditioning be easy ?!? You could just wind down the window.
If you don't believe me go and read the editorial on autospeed from a week ago. The editor there gives workshops who claim to be able to achieve this feat an absolute caning.
cheers,
monty
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Location:
melb
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 06:36
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what a shit thread! why did I click on this? it looked bloody crap just by the title. Oh how much power am I going to gain on my 4AG from a fuel cooler eh, gee i'm just busting to put money into that instead of some cams - NOT!!
stop dreaming I thought this was a practical forum?
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Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 06:55
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Monty,
I knew as soon as I posted that, an argument would start.
Actually, I would have argued on your side not so long ago, so you could probably change my mind, yet was presented with an actual situation on a car rescently that's air temp sensor was actually showing this to be the case, the temperature after the intercooler was below that of ambient. After a "that's not possible session" I had a look into it, and it's what was happening.
Admittedly it was on an sr20 with a garrett branded mack truck intercooler that is basically the width of the wheel track of the car, so it's not a normal situation.
I'm not going to explain it, I can't well enough to do it any justice. It's not something I have a theory on.
I saw it, measured it. Thought that's bullsh*t it can't happen, then checked it. And it was happening.
I'd be interested to read that editorial though. I don't really get as excited about editors opinions, but if you don't read/listen/think/test, you stop learning.
And without being too romantic about it I think modifying is as much about that as anything.
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 07:31
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Heat transfer is simple. The temperature of two masses will converge to a value somewhere between the original temperatures of each body. Hence you can't have hot air beeing cooled by warm air and ending up cold. Its physically impossible.
The only way that the intake air could be ending up cooler would be if there was an expansion of the gas but this would be useless in automotive applications because it would be the same as losing boost pressure. If you've seen it in real life then either one of the laws of thermodynamics is wrong or the set-up that you saw it on wasn't accurate. Was the temperature measured with the same thermometer at the same time? Was it under steady state conditions? There are a lot of variables that come into play and could have been misleading.
FYI the editorial is on autospeed but I'd be breaking copyright laws by posting it. sorry for the dud reference.
take it easy,
Monty
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 09:00
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| Celica_RA40 wrote on Fri, 21 June 2002 5:28 PM |
i would say it would stuff up the throttle response but also may have bugger all effect. if you have a look at your throttle body it may have coolant hoses going to it. you may ask why do they want to keep this hot? it is so that the air flowing over the throttle body doesnt condense and freeze to the throttle body and induce water into the engine.
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Yes it does have coolant hoses to it. Could that be why I notice no difference to peformance in cold weather? It's that efficent?
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Location:
melb
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 09:20
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coolant hoses are there only for very cold climates, not needed here. Do you see any of the twin carb setups on old motors like the 2tg freezing up. NO
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Location:
Sydney, OZ
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 10:47
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| Quote: |
FWIW, some of the Five Litre Touring Cars use dry ice in the inlet system to cool the air before it goes into the engine during the qualifying runs
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Bill have you ever a though of using a Peltier to cool the aircharge down? I used a couple of these while doing my major project for uni to cool a Photo-multiplier tube down to -30 degrees, the setup could easy be fitted to a car with a bit more thought...
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 10:52
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| Johnny wrote on Sun, 23 June 2002 8:47 PM |
| Quote: |
FWIW, some of the Five Litre Touring Cars use dry ice in the inlet system to cool the air before it goes into the engine during the qualifying runs
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Bill have you ever a though of using a Peltier to cool the aircharge down? I used a couple of these while doing my major project for uni to cool a Photo-multiplier tube down to -30 degrees, the setup could easy be fitted to a car with a bit more thought...
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Ah bugger it. Just squirt some nitrous through instead. 
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Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 12:28
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Monty,
I understand the laws your talking about, but couldn't explain what I had seen, so I thought there must be another contributing factor, just like you say, error etc.
If you think I'm saying an intercooler can cool past its own temp, don't worry, I'm not. It's only a passive cooler and can, as you discribe, only dissapate heat energy from the charge air.
And that is probably the point the Autospeed guy would argue.
The only thing I could think was cause it was a cold day, and this intercooler really is huge, out infront of the bumper, and very unlikely to suffer much heat soak, that the intercooler was below ambient temp before the measurements were taken (ambient measured as temp at the point of air intake compared to the air temp directly after the intercooler). I know the charge air can only go to the same temp (and has to be at absolute peak efficiency to get there) of the intercooler, but if the intercooler is below ambient then its possible.
So I spose I'm actually saying (or what I've witnessed) is that an intercooler can cool past the intake air temp, providing the intercooler's temperature is below that of the air intake.
And I dont believe that bends to many rules of thermodynamics?
Sorry for both the length and the thread hijack guys.
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Location:
Montrose, VIC
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 12:50
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One small thought - is there any chance the intercooler that was cooling below ambient had a water spray on it? 
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Location:
Gold Coast
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 12:53
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| jase wrote on Sun, 23 June 2002 4:55 PM |
Monty,
I knew as soon as I posted that, an argument would start.
Actually, I would have argued on your side not so long ago, so you could probably change my mind, yet was presented with an actual situation on a car rescently that's air temp sensor was actually showing this to be the case, the temperature after the intercooler was below that of ambient. After a "that's not possible session" I had a look into it, and it's what was happening.
Admittedly it was on an sr20 with a garrett branded mack truck intercooler that is basically the width of the wheel track of the car, so it's not a normal situation.
I'm not going to explain it, I can't well enough to do it any justice. It's not something I have a theory on.
I saw it, measured it. Thought that's bullsh*t it can't happen, then checked it. And it was happening.
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OK. I beleive all the physics behind this and even though I learnt all this at school, I've forgotten too much to explain it all.
BUT, I have seen intake temps below ambient too! It was on an SR20 with a massive intercooler too coincidently.
The pipe between the intercooler exit and the throttle body had frost on it close to the throttle.
I can't explain it, I believe the physics saying it's impossible, but I've seen it.
My only guess is evaporative cooling due to moisture on the intercooler.
[Updated on: Sun, 23 June 2002 13:04]
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Location:
Brisbane
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 12:56
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I think it has something to do with pressure drop in the inlet system due to (for example) a retrictive throttle or intercooler.
Think about it, the inlet charge (let's say 15psi) is cooled to ambient temp by the intercooler, then there is a pressure drop at some point after the intercooler which reduces the pressure to 13psi. We all know that compressing a gas causes it to heat up, and the reverse is true as well! So 15psi air at ambient temp becomes 13psi air at less than ambient temp. Makes sense, yes? 
This is just a theory of mine, I could be way off...
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 14:30
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But surely the pressure drop of an intercooler would be the biggest drop (if any) in the intake system?
And with a really big 'cooler, there'd be a fair pressure drop wouldn't there?
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Location:
Melbourne
Registered:
June 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 15:28
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I would follow mrshin's lead...
Everyone is very correct saying that a strictly air-to-air cooler cannot cool below ambient.
However, if a water spray is used this is quite possible! Through exactly the same mechanism's that cause you to feel cooler on a hot day if you spray water on yourself. This is evaporation.
An extension of the water spray idea would be to use a different spray eg Metho. If you've ever put metho on your hand you will notice it evaporates quickly and feels cold - same idea as the water - just works a little better!
Or use either with a solid like dry ice or a gas (during dyno runs some people spray nitrous on their intercoolers - although any rapidly expanding gas would work well). Even the idea of a refrigerated system has been toyed with, again there is an article on AutoSpeed somewhere.
Norbie's theory, although with good basis, has a fatal flaw (sorry Norbie! )
The problem is where the inlet charge is said to be at 15psi. This means it has positive pressure hence 'forced induction'!!! This car would have to be turbo...
The 'boost' on a turbo car is the pressure in the inlet manifold. 15psi is 15psi ABOVE AMBIENT. In a NA car there is actually a vacuum in the inlet manifold causing more air to be 'sucked' in, in a charged car (turbo or super) there is something 'pushing' it in.
Some companies have tried to overcome this vacuum through using what is called a "Ram Air' Effect. Essentially this puts an intake at the front of the car (or on the bonnet) which, when the car is at speed, 'forces' the air in at some positive pressure. Usually only enough to bring manifold pressure to zero or slightly positive instead of negative (vacuum).
As for frost on the piping? I find it hard to believe. (not doubting you guys saw it, just how it got there...) This would mean that the temp of the air in the pipe was at or below 0! (or was expanding rapidly enough to cool the pipe to zero!) Not really possible as i'm sure you'd agree!
I'm just trying to help people understand the basic principles behind all this so they can form their own theories and not be sucked in by marketing and gimicks!
And hopefully they can pass the information on so we all know a little more...
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 22:56
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| Quote: |
As for frost on the piping? I find it hard to believe. (not doubting you guys saw it, just how it got there...) This would mean that the temp of the air in the pipe was at or below 0! (or was expanding rapidly enough to cool the pipe to zero!) Not really possible as i'm sure you'd agree!
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You can have water condensation on things with the air below ambient but not anywhere near 0 though. Define 'frost'. 
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Registered:
May 2002
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Re: Intercooler on NA
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Sun, 23 June 2002 23:13
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I didn't see frost. There was some condensation. I did touch the pipe and it felt cool.
It had no external active cooling (no water, no dry ice etc.)
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Location:
Melbourne
Registered:
June 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 00:27
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Yes! Very true.
Here is how i define 'frost':
"A deposit of minute ice crystals formed when water vapor condenses at a temperature below freezing"
It was strutto who said he saw 'frost' - maybe he just meant condesation...
Water will condense on any relatively cool surface if the air is humid enough, quite right there!
As for what was going on to cool the intake charge - i'm stumped! But there must have been something other than just the intercooler... Either that or these guys are going to be extremely rich with their new 'law breaking' technology!
If the engine had not warmed up and even if the piping was at ambient temp it would feel cool to touch (as long as it was still below the temp of your fingers ~35). This is due to the high thermal conductivity of metals, that's why metal always feels cold when wood or fabric feels warmer!
Were these guys claiming that they could redude the intake charge below ambient or was it just something you noticed?
Isn't it fun to get people thinking...
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Location:
Brisbane / Gold Coast
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 00:50
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Jonny, yes, I've seen the Peltier devices but I don't think they've got enough capacity to do the job. They also suck a lot of power for what they do, so they're not all that efficient really.
Speaking of air zipping along and causing temperatures to rise or fall, FWIW, on the 747 we get a skin temperature rise of about 33°C at mach 0.86.
In a good engine, you should have an airspeed of about mach 0.4 or so past the inlet valves and up around mach one past the exhausts, so I wonder how much temp rise we're getting from that?
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Location:
Sydney, OZ
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 01:35
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| Quote: |
Jonny, yes, I've seen the Peltier devices but I don't think they've got enough capacity to do the job. They also suck a lot of power for what they do, so they're not all that efficient really.
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True, they were pulling something like 24A @12V (288W)
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 02:55
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FWIW I think that any frost or condensation on an intake pipe must be coming from an internal pressure drop (and hence expansion as per Norbie & my previous emails). The best way to check would be to simply measure the pressure drop between an area between the condensation and the compressor (expect high pressure) and an area with condensation (expect low pressure - but still above atmospheric). If this did prove that there was a pressure drop then you could investigate how much heat the gas would try to extract and so forth.
As has already been said you would expect to see the drop across the throttle (a deliberate restriction) and perhaps after an intercooler (an unfortunate restriction). In any case - its probably a bad thing because it means that the intake charge is being re-heated (ie absorbing heat from the atmosphere) and so your intercooling is being undone  .
I don't think these results could have occured through the intercooler being at below ambient temp. How did it get below ambient temp in the first place? It might feel cold but that is a result of its capacity to transfer heat away from your body - not because it is at a lower temperature than the environment. It would take a cold source (at a temp below ambient) to cool an intercooler down to below ambient, otherwise it will be at ambient like everything else in the local environment...
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Location:
Melbourne
Registered:
June 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 03:24
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Don't forget we were talking about intercoolers on NA engines here...
Also don't forget a restriction will create an increase in pressure (and hence temp) before it lets the gas expand again and cool a little.
So by passing the air through a restrictor of some type you are simply heating it up and letting it cool again - you can't get something for nothing!
You can see this by using the perfect gas equation learnt in yr 10 chem... PV=nRT i think?
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 03:30
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The initial question was about intercoolers on NA cars but the whole "lower than ambient" thing started with reference to a turbo car.
Putting an intercooler into an NA car would cause even lower pressures at the intake manifold and so lower density still. It may be fractionally cooler but whats the point when its less dense?
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Location:
Melbourne
Registered:
June 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 04:20
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Ok fair enough, i just assumed they were still on about NA cars when they said SR20, with no ref to DET.
But the temp at the intake manifold won't be any cooler than ambient. It can't be, no work has been done so you would be getting something for nothing!
As a said in my previous post the cooling effect of the air expanding after the restriction only offsets the heating effect as the air is compressed prior to the restriction!
Good point though, any gain recieved from a very slight drop in temp (even through the use of CAI) would be lost through the massive reduction in flow! (unless underbonnet temps were extraodinarily high!)
But don't forget cold air is more dense than warm air too...
And in the case of a turbo car... how does anyone expect to easily reduce temps by that much!
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 04:30
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| beena wrote on Mon, 24 June 2002 2:20 PM |
Ok fair enough, i just assumed they were still on about NA cars when they said SR20, with no ref to DET.
But the temp at the intake manifold won't be any cooler than ambient. It can't be, no work has been done so you would be getting something for nothing!
As a said in my previous post the cooling effect of the air expanding after the restriction only offsets the heating effect as the air is compressed prior to the restriction!
Good point though, any gain recieved from a very slight drop in temp (even through the use of CAI) would be lost through the massive reduction in flow! (unless underbonnet temps were extraodinarily high!)
But don't forget cold air is more dense than warm air too...
And in the case of a turbo car... how does anyone expect to easily reduce temps by that much!
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Mmmm, makes me wonder now. Would a turbo be better off without an intercooler?
If the air coming out is less compressed/dense, then what's the point of a turbo with an intercooler?
Let me know if I'm way off. Yes I know that hot engine bay requires an intercooler in circumstances, but put that aside for a second.
(Who would have thought my crazy Idea that I scrapped near the start would end up with a dicussion on thermodynamics? ).
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Location:
Melbourne
Registered:
June 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 04:57
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Yes you are way off!
A turbo engine is in no way better without an intercooler! The only mild benefit is a slightly sharper throttle response due to a shorter inlet tract.
Here is an example:
Say you have an ambient air with a temp of 20deg. Your turbo compresses to this to 15psi. Now the temp of the 'charge' air (out of the turbo) is about 60deg! (this figure depends on heaps of things like turbine compressor maps and turbo efficiency).
If you ran this 60deg air through a large intercooler with 20deg air flowing past it you could expect the charge air to drop to maybe 30deg. (depends alot on the intercooler, hence bigger = better)
The 30deg air at 15psi is alot more dense than the 60deg air at 15psi. More dense air means you can put more fuel in with the increased amount of air and hence get more power.
Also, with a cooler charge there is less chance of detonation (knocking/pinging/pinking/pre-ignition) so you can run more ignition advance and again get more power!
Hope this helps clear things up!
PS.
in a NA car the lowest intake temp you can get is ambient. The problem is most people put their filters in their engine bay where the temp is much higher after the air has gone through the radiator, past the exhaust, over hot engine components etc. As you know if you open your bonnet after driving it can get pretty hot in there!
So Cold Air Induction attempts to get air directly from outside the car where it is at ambient.
Also why if you change the stock airbox (often it has some form of CAI) for a pod filter in the engine bay you can actually reduce power!
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Location:
Brisbane, QLD, Australia
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 06:25
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Ah well. I just said what I did because I got the impression that the intercooler is a restriction and the air coming out of it is less compressed than the air going into it.
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Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 06:58
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Yes, I meant an sr20 det, my bad.
No, I dont think its a good idea to put an intercooler on an NA car.
Ambient was measured at the point of entry of the intake. (Ducted from the front of the car to a very well sheilded, but not sealed, box under the bonnet.)
The intercooler was constructed (not bought) from a cut down (height not width) Mack truck core. The core was embossed with a garret log (maybe that's why......). It's huge.
It hasn't got external cooling. No water etc.
The air temp measured after the intercooler was lower than that measured at the point I descibe above as ambient.
I've got some pics if anyone is interested.
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Location:
Sydney
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 07:10
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Post the Pics!!!
lets see if there is a restriction.
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Location:
Gold Coast
Registered:
May 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 07:20
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| beena wrote on Mon, 24 June 2002 10:27 AM |
Yes! Very true.
Here is how i define 'frost':
"A deposit of minute ice crystals formed when water vapor condenses at a temperature below freezing"
It was strutto who said he saw 'frost' - maybe he just meant condesation...
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Err, my bad in quite a few areas but I did say I've lost too many brain cells to argue this effectively...
It was a DET. I aint lost enough brain cells yet to intercool a NA sr20.
It was not a claim by someone. It was something I noticed.
OK it was condensation, not frost, that I saw. There was no water spray tho.
I think SXer may be on to something with his pressure drop idea. I assumed condensation was a good thing but what he says does make sense. The piping from the intercooler outlet to the throttle body was rather long and bendy.... maybe this caused enough of a pressure drop to form condensation?
I don't know... my brain hurts. 
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Location:
Melbourne
Registered:
June 2002
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Re: Intercooler on NA
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Mon, 24 June 2002 08:14
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Jase,
I'm intrigued.
So the 'ambient' temp was measured in the engine bay at the airbox.
And the final temp was measured after the intercooler, i assume somewhere near the throttle body.
The intercooler was a standard, nothing special, large air-to-air unit.
That's what i got out of it.
Now my questions:
Do you know roughly how much boost was being run?
Do you know if the Turbo was a stock T28 or different?
Do you remember roughly what the temperatures measured were?
The only thing i can thing of is that the intake temp in the engine bay actually was above the ambient air temp by quite a bit and the massive cooler core managed to bring the charge air down close to ambient.
If large boost is being used then charge air temps tend to skyrocket as the turbo gets well out of it's efficient range.
A turbo running low boost at it's maximum efficiency will produce the lowest charge air temperature which could possibly be cooled to ambient by a large cooler but certainly not below.
Also remember that the rate of cooling depends on the temperature difference - so hot air will be cooled quickly at first and as it approaches the ambient temp it will slow down and take a long time to actually reach it.
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