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Has anyone on here ever used a small intercooler as a cold air intake, without a turbo or blower? i put a poddie on but is in the same place the air box was. I feel its going to be sucking in rather warm air generated from the header. One of my mates has a new small IC which he doesnt need and we thought we could use it to cool the air in my 5, even though i dont have a turbo. In theory it sounds good but would it work? i've seen some ingenious CAI's on this forum that would work fine(i've been eying off my dad's V6 Camry for months now ), but this idea seems like more fun for some reason.

Any thoughts guys?

saw a thread on the idea at miata.net, is kinda pointless since the best that an intercooler can do is bring the temp down to the air temp outside. it'd just add more of a restriction to the system, so worser for non force inducted.

though maybe theres some gain with a water to air intercooler, far too much cost though for what you'd gain i'd think...

the restriction problem was one i had in the back of my mind. However was not sure on how much effect it would actually have. as a general rule 7degrees Fahrenheit cooler = 1% more power at mid-high RPM. I've measured the temp near the filter on a 38C(100F) day and i got a reading of 168F. 68/7=9.8%. Say i'm getting 95Kw at the wheels now, that means i would get a power increase to 104.5Kw ATW(even more on a cooler day). However increasing or decreasing the air intake pipe length changes the dynamic tuning and will change the power curve. will it loose power or just simply shift it to a different spot in the rev range?

Mate, if it is on offer for free, or try before you buy basis, you can't lose much by giving it a go.

IMHO it will not give you any additional power, and will probably lose you power due to the massive restriction it will place in the intake tract.

Any cooling that it provides will be beneficial, but will not offset the declined cylinder filling you will get due to reduced intake flow. And please remember that the efficiency rating for an intercooler is such that for every deg difference between intake air, and ambient air (on the cooler) you get much less than a deg reduction in the temperature of air hitting the inlet manifold.

The shorter intake tract will probably change the characteristics of the torque curve of your car, but again I suspect that this will have a lesser effect than the increased restriction in the intake.

I had some of these on my previous car....and have one in the shed for the MX5 , as yet unistalled.

Andrew wrote:I had some of these on my previous car....and have one in the shed for the MX5 , as yet unistalled.

Seen a few of these. Make sure to get base temp readings before you install them to quantify their effectiveness. If it works, then I reckon it's a worthwhile mod. May even qualify for a gb eh?

As with shorter/longer intake affecting torque curve, I agree, and 95% of the time it follows the rule of shorter intake = better low-end power at the expense of top-end and vice versa.... (more effective with individual throttle bodies running individual intake trumpets)

But then there are exceptions to the rule which is difficult to explain; eg. is the K-series engine in the Lotus Elise.
Due to the cramped engine-bay it is difficult to upgrade the standard intake tract with a bling intake. The UK tuners have actually found that sticking a pod straight onto the throttle-body works very effectively with little drop in power in all rev-ranges.

Andrew wrote:I had some of these on my previous car....and have one in the shed for the MX5 , as yet unistalled.

I think this will work for a few minutes, untill heat soak set in. Then its going to be the same as normal.

I thought the idea of the spacers was to eliminate heat soak?

As far as i know, most of the heat absorbed into the intake system comes from conduction as the cast inlet manifold acts as a heat sink of for the cylinder head.

A mechanical engineer friend of mine told me tha the most effiecnt method of heat transfer is conduction, followed by radiation then convection.

If we can insulate the conduction componant of heat transfer, then i would argue that total tempretures will be significantly less as the only heat sorces will be radiation and convection, both of which are far less efficent means of transfering heat.

How does this translate to seat of pants power increases? Dont know, but i will argue that it would make a more significant increase to performance than an intercooler on an non turbo car.

sirbob wrote:I thought the idea of the spacers was to eliminate heat soak?

As far as i know, most of the heat absorbed into the intake system comes from conduction as the cast inlet manifold acts as a heat sink of for the cylinder head.

A mechanical engineer friend of mine told me tha the most effiecnt method of heat transfer is conduction, followed by radiation then convection.

If we can insulate the conduction componant of heat transfer, then i would argue that total tempretures will be significantly less as the only heat sorces will be radiation and convection, both of which are far less efficent means of transfering heat.

How does this translate to seat of pants power increases? Dont know, but i will argue that it would make a more significant increase to performance than an intercooler on an non turbo car.

Exactly.

My previous car had a 2.5l V6 that after a good run you'd be hard pressed to touch the inlet manifold for more than a couple of seconts before the spacer were installed, after installation it wasnt an issue, was warm but not stinking hot.

To follow on from this thread hijack ( ) if you were to remove/divert the hot water flow from the intake then that too might reduce the temp of the air entering the engine.

A question would you not need some form of air temp sensor and/or knock sensor to gain the most benefit from the OP idea of using a intercooler on a naturally aspirated car?

J

The point of the intercooler is to bring temperatures down to ambient due to heat from 2 factors:
a) the device doing the compressing being hot
b) compression of air resulting in the same energy in a smaller volume of space

Both of these will warm air going in - so you use an intercooler to help transfer the heat.

If anything, putting an intercooler on an NA car will hurt performance by adding weight.

Any gains from such a setup over the factory setup are more likely than not going to be from improved intake design - not the presence of the intercooler.

if i was you id give it a go, but the only accurate reading you will get will be on a dyno. before and after scenario. When i rev my motor from the throttle body and then put my hand over the BOV the air feels cooler to what is out side. And thats in a stationary car. As for it being restictive, grab a intercooler next time one is floating around etc, put your mouth on one end and blow, feel the restriction. there is hardly any if any. whether it increases your performance who knows but i dont think it will send it backwards. But the weight might!

glen73 wrote:if i was you id give it a go, but the only accurate reading you will get will be on a dyno. before and after scenario. When i rev my motor from the throttle body and then put my hand over the BOV the air feels cooler to what is out side. And thats in a stationary car. As for it being restictive, grab a intercooler next time one is floating around etc, put your mouth on one end and blow, feel the restriction. there is hardly any if any. whether it increases your performance who knows but i dont think it will send it backwards. But the weight might!

You're BLING factor will be off the scale with the intercooler though !