Intercooler Backpressure Test!

[Reaper1]

So, I decided to be all engineer- like and scientific and to do an experiment before installing new parts on my car. I figured I'd also share what I found!

I took a page out of Gus's wisdom and did a backpressure test on intercoolers I had laying around to see what the differences were and if I was actually going to see a net gain from the proposed part I wanted to install.

Here are the results!

My homemade manometer read 22" of water at atmospheric pressure. I was reading on the pressure side, so the lower the number, the more backpressure there is.

The pipe alone (2.5") on the "hi" setting read 21.5", on the "low" setting read 21.75"

The stock intercooler read 15.5 on "hi" and 17.5 on "low".

The CX Racing intercooler I had on the car read 16 on "hi" and 18 on "low".

Finally the fake "Spearco" intercooler I am going to run read 18.5 on "hi" and 19.75 on "low"

The core measurements were taken like this: Length was ALONG the tubes, Width is how thick the core is, Height is perpendicular to the tubes, and then of course the tube count.

Stock: L=11.5, W=3, H=6.75, #of tubes = 10
CX Racing: L=19, W=2.75, H=6.25, #of tubes = 8
"Spearco": L=8, W=3, H=18.25, #of tubes = 27

The blower being used is an electric leaf blower rated at 165mph and 125mph on the hi and low settings respectively out of a 3" pipe.

This is the overall set-up, minus the yard stick I was using to measure the manometer.


This is the stock intercooler I used.


This is the CX Racing intercooler I have been running for a few years.


This is the "Spearco intercooler I'm swapping to:


This is a close-up of the connection to my Manomoeter set-up.



This is the chart I made in Excel to show the results visually. I'm VERY happy with what I've found and it makes me feel even better that the fake "Spearco" I'm going to install flows as well as it does.


Again, I'd like to thank Gus for the inspiration to do this! Your spirit lives on, my friend!

Later I'll detail the manometer set-up so anybody who wants to build one, can!

[turbovanman²]

Love the safety shoes,

Great test, now before taking it off, do a pre boost check, you have a boost gauge already so your halfway there.

You said fake Spearco, so did you spray paint "spearco" lol.

[cordes]

I still can't see the pics, but I appreciate the writeup.

[Directconnection]

Yeah... is it a spearco or a fake "budget" Spearco?

[Reaper1]

Simon, I know I set my boost at 22#'s, but the controller reference is from the intake manifold, so it *should* stay the same regardless of the restriction in the system. Now, if I had a boost reference off of the turbo, THEN I could have a meaningful number for you. Unfortunately I've already taken the old IC off and it's NOT going back on. The whole nose of the car is off. I am intending to fabricate directed air ducting for the intercooler, oil cooler, and radiator as well.


I got it from an e-Bay seller YEARS ago, but custom made to my specs. It's not a REAL Spearco to my knowledge.

So, it's a FAKE Spearco as far as I know.

[turbovanman²]

That's ok, figured if it was running, you could do a few tests.

Gotcha on the "Spearco"

[tkelly27]

If I remember right, the boost will still change, and I'm not sure why. A friend of mine uses the intake manifold for the WG pressure source and when he swapped from an SRT-4 IC to a proper unit in his van he found a 3-4psi increase.

It would have been nice if you had recorded the delta T for your old IC. I have read that with the inlets and outlets on the same side like your spearco clone it can cause the temperature change to not be as high as it could be. It sure is convenient, and you have to love the low pressure drop.

Looking forward to your future findings!

[GLHNSLHT2]

that CX racing i/c is horrible. Cool Gus test

[Reaper1]

Yeah, the delta T would have been nice, but I wasn't in the position to do it, other wise I would have.

I will say that honestly with my set-up, and my future set-up, the delta T is important, but not AS important as flow. I'm probably going to upgrade this core in the future as well.

I also run Meth injection, and honestly it does such a good job the I/C is almost a redundancy. Once my new engine is built and such, I'll have a delta p test to see how bad this core is. I'm fairy sure it will be bottleneck for the new set-up.

Thanks on the props!

[BadAssPerformance]

Nice work!

Flow is only 1/2 the equation tho... like the 1080 CFM spearco flows great, but is not very efficient.

[Shadow]

Agreed, it's the shortest pass with the most volume flow through that pass which is why it shows better, but it will have the least effect on cooling what's going through for that same reason.

[RoadWarrior222]

yah you've got a bunch of contradictory requirements in an IC, first that it should flow well, but also that it should expose as much surface area to the air as possible to enable heat removal. Which means surface friction, so smaller pipes and narrower passages mean better cooling but less flow. Then also you're fighting the surface area vs volume thing, where you can't go large and just have huge lengths of it, because the ratio of surface area to volume is too low.

So there's probably a great deal to be said for matching an intercooler to your particular setup. Because bigger might not necessarily be better for your current boost level and airflow requirements. There's too big, and too small and somewhere in the middle some good matches... until you up the boost, or calibrate for another 2000 rpm or something.

Kinda makes me think of building a special IC to see how that does, spin the air in a tube so it centrifugally separates, into a warm layer in the middle and a cooler layer on the outside, then have a heatpipe down the middle, to pull heat from the warmer layer.

[zin]

One aspect that never seems to get any attention, but is critically important to any heat-exchanger's performance is the velocity of the cooling air through it.

Unfortunately, that's not an easy test to do, about all you can do is build a shroud around and ducts to the intercooler. Unfortunately, that's not something many of us have experience doing...

Mike

[Reaper1]

Do you mean the velocity of the charge air, or the cooling air?

I will be building shrouds for this intercooler. ANY air that goes in the front of the car will only have 2 choices, and once it makes a choice it can NOT change it! The one choice will be to go around the intercooler and then enter the exposed part of the condenser and radiator, OR go through the intercooler, then the oil cooler, then the condenser and radiator. These will be completely separate from each other from the front of the car to the condenser, which is full width.

The oil cooler has its own dedicated fan that will turn on either with the radiator fan, or I will manually be able to turn it on. This will also suck air through the intercooler because of how I have designed the positioning of everything.

[John B]

There's too big,

Sacrilege! It's only too big when it sticks out so much that it creates more wind resistance than it makes power.

[zin]

The cooling air's velocity.

[Aries_Turbo]

i thought those "spearco" intercoolers of that style were spearco cores but generic endtanks.

Frank bought one like that and sold it to me.

the newer CXRacing large intercoolers are pretty good. a local guy is pushing 1000whp through one with ease.

Brian

[cordes]

i thought those "spearco" intercoolers of that style were spearco cores but generic endtanks.

Frank bought one like that and sold it to me.

the newer CXRacing large intercoolers are pretty good. a local guy is pushing 1000whp through one with ease.

Brian

The one I have has Spearco end tanks, but I'm not sure about the core.

[Reaper1]

The cooling air's velocity.

Ah, good. Then my last post was valid!

[Directconnection]

yah you've got a bunch of contradictory requirements in an IC, first that it should flow well, but also that it should expose as much surface area to the air as possible to enable heat removal. Which means surface friction, so smaller pipes and narrower passages mean better cooling but less flow.

Are you sure? #1) A smaller "pipe" has less surface area to dissipate heat, and... #2) the smaller pipe causes more velocity, where as the larger one slows down the airspeed for more effective cooling (and also flows better-er ;-)