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intercooler inlet and outlet

vtecds1

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Does the location of the inlet or outlet matter on an intercooler? I have a side to side intercooler with the inlet on the top and the outlet on the bottom. I`m planning to have it rewelded since the previous owner didn't center the intercooler because of the clearance issues with the bumper support.
 

broxma

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It does matter quite a bit depending on the setup. Think of airflow in the core as though it were a liquid without gravity. Let's make an example where you have a 14" tall core with both inlet and outlet on the top or bottom. even given boost pressure, the air will flow according to least resistance. This means that the channels directly in front of the inlet will have the most flow and the ones further from the inlet less. A remedy for this is an internal baffle which redirects some of the flow towards the other side.

When efficiency figures are given for a certain intercooler, a reputable builder will factor in these losses. Many Ebay brand intercoolers are stated as being able to cool a certain charge at a certain pressure loss, however they often use a damn near perfect cooling condition to achieve this number. This is also not to say that more power cannot be run through an undersized intercooler, just that it will have a sharp fall off in efficiency. The undersized stock intercooler is a good example; There is way more air going through it than it can reasonably cool, but it still achieves some cooling.

My Evo has a 24x17x4.5 API core with custom tanks and internal inlet baffle built by guys at BIC. It is larger than almost any core available and even still we only rated it at around 650-725 as far as its theoretical maximum hp support. These insane claims by most companies are mostly that, insane.

One major component of IC design overlooked is endtank design. I have seen many designs for the VR4 where the inlet hits the tank at a 90 degree angle. This forces the air to hit the flat wall of the tank, stop and make a 90 degree turn, the worst possible flow design ever other than stopping and turning around. The numbers for direct energy lost due to different curves and transitions of airflow are available all over the internet. If you look up this information, you'll see that by having this 90 degree inlet design there is a direct percentage loss of power due to the change in direction. Not so surprisingly, by switching to a design with an improved flow the net increase is in torque it seems. The dynos we have done comparing badly designed vs. internally baffled smooth transition designs have shown a greater increase in torque than HP, some case twice as much.

I am not an expert on intercoolers, but my old boss is, and he has a way with long winded diatribes about every auto related fact or figure ever known to man. I learned more in the year or so I worked with him than I had in the previous 10.

/brox
 

vtecds1

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Thanks for the good info fellas...I`ll see what my best options are without sacrificing the airflow. If not, I`ll just stick with the original set up.
 

vtecds1

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Sorry to bring up an old thread... Reading the article, It doesn't seem to be a bad idea if I was to flip my intercooler around so that the "hotside" would be on the bottom and the "cold side" on the top. Am I wrong?

The first one is my current set up. The second pic is how I want to change it.


 
Last edited:

NateCrisman

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Brent at JMF flipped the endtank on my 24 x 12 x 4 XS power (ebay) fmic core. We did it purely for fitment and pipe routing, but It likely also helped the overall efficiency by not having the inlet and outlet directly facing each other on the bottom most rows of the ic. He also welded a turbonetics 2.5" 90* cast elbow to the endtank since we needed a really tight radius to keep the core centered in the bumper (it's still about 1" to the pass side)

Before:
514203416_zS8J2-L.jpg


After:
617894713_o9wng-L.jpg
 
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vtecds1

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So do you think it would be a bad idea? The pics will show you the reason why I want to change it...





 

I would just buy another core. If that one cant be centered AND not stick out the bottom then just replacing it would be better. An ets style core is long than it is tall and is plenty big while still being able to be centered and not hang out the bottom.
 

vtecds1

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It`s definitely workable as to being centered and not having the bottom stick out. That being based on if I can flip the intercooler around or reverse the hot and cold side. There's enough room behind the bumper to play with, I just don`t want to have to cut anything to try and make it fit.
 

cheekychimp

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What is the company that does the intercoolers with the curved end tanks. They looked awesome!
 

Galantvr41062

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Aug 20, 2007
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plymouth, MN
I have welded up my fair share of inter cooler setups. I welded up a FMIC kit for a DSM using the tried and true around the radiator short route using a PTE bar and plate core. This replaced a around the radiator tube and fine design. The out right gains were not impressive but we found from back to back testing the bar and plate would dissipate heat a lot better then the tube and fin, thus ending on top. I have also welded up 2 FMIC kits for a 3000GT, using the same core but different turbo setups. One setup I welded up end tanks that fed in the top on one side and out the bottom on the other with smooth flowing curving end tanks. This car had twin 50 trim turbos running 33psi on race gas and making 700awhp. The other car has end tanks that are as small as possible, the end tank is less then 2" thick and has twin inlets from one side and 1 outlet on the other, both twards the bottom of the core which is 24" x 12" x 4.5" bar and plate PTE core (the same for both setups), rated at 1200hp. This ratting should be a thermal dissipation, this much heat in and this much heat out. But this other car has twin 13g's from a subaru and is running 20some psi, intake air temps are similar for the 2 cars, but I do not know the pre intercooler temps for either setup.

~John
 

vtecds1

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Quoting cheekychimp:
What is the company that does the intercoolers with the curved end tanks. They looked awesome!



I don't know who makes them, but I kinda like how the intercoolers on the Skittles look. Just seen one on the road this morning.

Well, after 2hrs of looking where all the bolts that hold the bumper are...I finally got it off last night. Looks like I have to move the intercooler about 3.25' inch to get it centered. I figured it's going to cost me about $50 in materials to redo almost all my piping for it to work out. The powdercoating and the welds will be done by my friend( hopefully free of charge).





Do you guys think the previous owner did it like this for a reason? I'm giving him the benefit of the doubt by saying that he did this so that more air can get to the radiator. It was a Vegas car after all...
 

^The grille and stock fans do plenty of cooling even it the fron took up more of it. He probably did it because he thought it was good enough there and not really cared what it looked like. You'll make it right Im sure.
 

fuel

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I gotta ask is there really a need for such a large intercooler?
 

vtecds1

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^^^All I know is that the bigger the turbo and the more air that is being pushed, the bigger/wider or taller intercooler is needed. As for the reason why the po picked this specific intercooler...I have no clue. Hopefully someone can chime in that can give a more detail answer than I can. /ubbthreads/images/graemlins/smile.gif

Here's some pics of my work in progress. I`m trying to salvage as much of the intercooler pipes as possible by moving them around. I`ve got one configured that makes it a really good fit, but my concern is where the blow off valve is. My question is...does it matter where the bov is placed? I did some research and there is too many opinions out there on where it goes. Some say a couple of feet from the tb, some say before the intercooler and some say you dont need one.








 

broxma

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The intercooler on the car above looks to be relatively inefficient which certainly explains the size. I can visually see the individual crimps in the external channels which means fin density is fairly poor. In addition the internal channels appear to be rather large. What this means is that for a given "B" (Height) measurement you have few internal channels than a top dollar core. This means less flow for a given frontal area. None of this matters as that core, even as inefficient as it is, will probably cool down around 300hp, but it does illustrate how companies base the HP claims only on size.

A few things about cores themselves. On a cross flow design you have three measurements. "A" is width, "B" is height and "C" is length. This may not be industry standard but it is how they are used to at the shop.

The width (A) is important that it not be so large that airflow stalls somewhere halfway through the core, resulting in lower efficiency at the backside of the core. An example of this would be a 6" "A" measurement on a street car. In addition, as the air passes over the fins it heats up, so by the time it gets to the back inch or so, it's not cooling anything anymore. The largest "A" measurement you would want for a street car is probably 4-4.5". I'd say optimally for cost and efficiency, 3-3.5" is ideal in most cases.

The "B" measurement basically determines your frontal area and is usually restricted by the space available. Remember that intercoolers don't have high efficiency as radiators. The air passing over them is what counts, so an external channel hidden or blocked off behind a bumper beam is a hot channel. When I build my custom cores, I usually try to put external channels on the top and bottom plates so that every internal channel has two external channels to cool it. This measurement is probably the most important as it dictates the overall number of external channels.

The length "C" is an interesting one because of the way people look at it. They always assume longer is better. That is not a pun. Longer is better to a point, also not a pun. Lets say I have a 24 inch long core and my overall efficiency rating sits around 90%. By increasing the length another 4 inches, you won't see a proportional increase in efficiency. It might be closer to an additional 1%. So for an increase in length of some 15-20% you get a net result of 1% efficiency. However, if you were to take that 24 inch core and drop it down to 18", the next lowest common size, you might see a drop off in efficiency of 5-15%, throwing a number out here but you get the idea. Length is not proportional to efficiency.

The measurements of a core are not just guesswork. Larger is better to a point. At some point all three measurements can begin to hurt you.

The intercooler above does have what I would call optimized inlet placement, however the upturn at the inlet side is a bit of a power robber. It would be better to make the inlet turn an immediate 90 degrees(Mandrel) out of the end tank rather than drop down and around. Diagonally opposed inlet/outlet placement is best on cross flow intercoolers with no internal baffle to redirect flow. With an internal baffle the diagonal placement is less important.

To illustrate the point about the efficiency model of fin density, baffling and turbulators, I have a core which I would say is probably equal to or more efficient that the core posted above. I cannot see all aspects of the above core but if the fin density, channel size is an indication of the rest of the design....

Then this core...

ofrhjt.jpg


2lx9oir.jpg


...is more than likely more efficient and is 3.5 x 6 x 18. That is the qualitative difference between Ebay/GhettoChrome cores and top quality cores such as API. It is literally that much.

/brox
 
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