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Intercoolers efficiency?

Jussi Alanko

Member
Joined
Jun 5, 2020
Location
Finland
Doeas anyone measured an iat after and before the intercooler.
I wil make some calculations at home and i need a some sort of efficiency ratings from these ic:s.

What is efficiency at some ebay cooler, or what is an efficiency for exapmle do88 240model intercooler.

Here is a comparison with 240 original ic and a aftermarket do88 one.

ICM-140-Temperature_diagram.jpg


If somebody has measured iat:s i can calculate efficiencys.
 
I have called at least 10 different places which sells intercoolers and nobody doesn't know anything about their ic:s efficiencies!!!
 
Hi Jussi
I'm interested in similar information.
I want to crank boost pressure way up and use water/meth injection to keep things cool.
I started wondering how I would know when I should start injecting rather than choose an arbitrary RPM or boost figure.
I have puchased 4 cheap temperature sensors (Chinese of course) & intend to place them at the air intake, turbo outlet, intercooler outlet and inlet manifold.
Even if they are not that accurate, it will give an indication of what is happening as temps rise, when the turbo is blowing too hot and what effect spraying water into the turbo and water/meth into the intake will have.
I purchased my intercooler years ago when I did the +T on my 240. My decision way based on fitment rather than efficiency!
Tim
 
This is what i'm probably gonna buy:

IC-260_1.jpg

Its 300*455*102mm and here is pressure drop in function of cfm:

IC-260_2.jpg

In a one internet calculator says that 300hp needs 208cfm, so this ic will drop pressure at this kind of hp level about 0.4psi
 
Big fat aluminum eBay IC's are lousy? NOOOOOOO!

(Ahem, I'm trying to blow 550-ish HP through one similar to what he tested and found lacking)
 
Where?s Kenny? He just did this on his dyno yesterday.
How do people make up for the low air flow across the core when the car's on the dyno? It seems like you'd end up measuring how good a heat sink the intercooler is rather than how well it gets rid of heat.
 
Big huge fan in front of the car intercooler radiator is how they blow air by it at dyno..

Just make sure your car is double secret strapped down, don't want car jumping off dyno and killing your biggest fan.

Yeah Kenny found out that the factory 940 big later style intercooler is better then the ebay ones, but the garret one was the best.

<iframe width="560" height="315" src="https://www.youtube.com/embed/AS81r8c_3A8" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

12.61 in the quarter mile. RIP..
 
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Typically for an air-to-air charge cooler, we talk about effectiveness, which is not exactly efficiency but it's similar.

For a cross-flow heat exchanger, which is what an air-to-air intercooler typically is, effectiveness is a ratio of the difference between the inlet and outlet temp of the hot fluid (charge air or "boost" in this case), and the difference between the inlet temp of the hot fluid and inlet temp of the cold fluid (ambient air in this case).

So, you need to measure the following temperatures to get a number for effectiveness:
Temp of the ambient air flowing across the cooler
Temp of the boosted air coming into the cooler
Temp of the boosted air coming out of the cooler

You also need to know the specific heat capacity rates (C) of both fluids (both are air in this case).

a05frm01.gif


Another thing that's interesting is the pressure of the boosted air coming in and coming out, and how much that pressure drops as the boosted air flows through all the little internal channels in the cooler. There is a temperature drop across the cooler, which is the goal, but there's also a pressure drop, which is an unwanted side-effect because it makes the turbo's compressor work that much harder to get to the same end pressure in the intake manifold.

A kind of ballpark standard figure to use for an aftermarket air/air cooler is 70% effectiveness. For an average air/water cooler, I use 85% - they are more effective due to the higher heat capacity of the cooling fluid (water). General guidelines for selecting a cooler are that you want to minimize the pressure drop (aka boost loss) across the cooler, and the simple way to do that is to make the cooler as big as possible given the space you have in the vehicle. Another important factor is design of the end tanks and charge plumbing, which both need to be carefully shaped to minimize pressure loss and ensure even distribution of airflow inside the intercooler.
 
And KWIW, Kenny wasn't measuring temperatures before/after, or even PSI before and after, just measuring the HP created. With everything else the same, rotating three different IC's through and seeing how much HP they made.

It would be an assumption that the eBay IC was producing a larger pressure drop, more so than the cold side temps being higher.
 
Just to add another (important) element of efficient IC design beyond tube/fin construction is the placement of I/O, & whether deflectors are added to guide the flow in (most) cases where the I/O are not centrally located relative to the core.
 
To help keep the engine cooler

negative. it's up for accessibility and whatever monitoring/diagnostic stuff gets connected (like the rpm pickup, and pressure input, etc). there's no requirement for the hood to be up, but it makes life easier. the cooling is handled via fans, etc.

the way we tested the intercoolers was by keeping as much 'constant' as possible and noting the power produced as well as any significant variances in manifold pressure and temperature.

As far as companies not providing that kind of information, most of them probably don't know and likely don't care lol
 
But, how can you measure how effective an intercooler is if flow with hood open != flow with hood closed? Is there a well known conversion factor to account for that?
 
The amount of air a big ass fan blows at the front of the car is probably not the same as the amount of air hitting it at various speeds.

And the load of the dyno isn't the same as the load of the real car on the road.

Etc, etc. Bigger variables at play. I really don't think you're going to see a noticeable difference in dyno numbers between hood open, hood closed. I'd be mildly amused to see Kenny test that though.
 
conversion for what? a bigger concern on a dyno is the overall volume of air going over the heat exchangers. hood up or down doesn't have as much of an effect on that as you would think, as I said above.

If you've set up things poorly with regards to ducting on the front of your car, all of your exchangers are likely to suffer performance hits in the heat rejection department.

The question I think you meant to ask was this: How can you measure effectiveness if flow stationary != flow moving?

To that I say, you'll get a pretty good idea, as well as putting additional data points in there that're easier seen on a dyno, such as pressure drop (swap to another intercooler, lose hp. it had to go somewhere, and it's not just heat)
 
The semi-interesting, though not totally unexpected is A) how good the stock Volvo intercooler actually is. And B) how ****ty even those thick ass chinabay intercoolers are. There’s way more engineering involved in making an efficient intercooler besides some thick ass block of tube and fin aluminum.

I would be curious how much efficiency is gained from one of those do88 intercoolers since they’re supposed be be group a replicas. Thinking not very much.
 
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