IC sizing

smokinVE said:
Well I really wasn't thinking then, thought you meant water...

Okay so does the above statement of IC's being rated at 20PSI hold true for all? Let's say I want 1,000 HP (just a round #) but I have 60# of boost, do I need a 3K cooler?
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The only way to tell is checking iat. Typically air temperature on your twins at 60psi will be less than a single at 60psi. Requiring less intercooler.
 
After reading some Bell and Garrett tech. I would say you need to figure out the efficiency or "effectiveness" of each cooler. I believe it was Garrett that mentions a/w being around 80-85% effective. Meaning 200* in would be 40* out, which seems incredibly low.

you'd need to know the outlet temp of your primary at max boost, effectiveness of interstage cooler, and outlet temp of secondary at max boost. You could use STAP as a baseline for calculations.
 
j.fondler said:
After reading some Bell and Garrett tech. I would say you need to figure out the efficiency or "effectiveness" of each cooler. I believe it was Garrett that mentions a/w being around 80-85% effective. Meaning 200* in would be 40* out, which seems incredibly low.

you'd need to know the outlet temp of your primary at max boost, effectiveness of interstage cooler, and outlet temp of secondary at max boost. You could use STAP as a baseline for calculations.
Click to expand...

Your exit temp seems low because the numbers your using for inlet temp are low.
 
j.fondler said:
After reading some Bell and Garrett tech. I would say you need to figure out the efficiency or "effectiveness" of each cooler. I believe it was Garrett that mentions a/w being around 80-85% effective. Meaning 200* in would be 40* out, which seems incredibly low.

you'd need to know the outlet temp of your primary at max boost, effectiveness of interstage cooler, and outlet temp of secondary at max boost. You could use STAP as a baseline for calculations.
Click to expand...

That's not how it works.
You're ignoring the biggest factor which is ambient air temp (Newton's Law Of Cooling), and your second biggest factor which is air flow (90% turbulent convection which is much harder to calculate).

I'm assuming they have some standard, or maybe there's an SAE one, that states testing at a certain temp in, internal flow, ambient temp, external flow, lighting (radiation), mounting (conduction), etc...
For that matter, assuming nothing would break/melt, if it was 1,000,000F at the inlet, and 0F ambient, your heat transfer would be through the roof because of the delta in temperature.

Specifying an IC is tough because the larger you go, the slower you are to spool and response goes down. Too small and you get hot air. You want a free flowing system, so to get the surface area needed to make an efficient cooler without building back-pressure, you make a ton of small passages and your inter cooler gets large quick. Another factor is what's surrounding it like a radiator then engine behind it to block wind and slow flow, or a crammed engine compartment that heat soaks.
The best thing you could do would be to test first hand. The second best would be to flow test your inlet piping to the intercooler, after the cooler, and then the cooler to make sure it's not the bottleneck. The cheapest and quickest thing to do is to buy off the shelf or copy a known working setup.

IMO a water to air is much more efficient if you can use ice water headed down the track.
Spraying an air to air would be a good alternative for track use.
And getting the most efficient, air to air cooler would be the best for street use.
 
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kjpcummins said:
Your exit temp seems low because the numbers your using for inlet temp are low.
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CorneliusRox said:
That's not how it works.
You're ignoring the biggest factor which is ambient air temp (Newton's Law Of Cooling), and your second biggest factor which is air flow (90% turbulent convection which is much harder to calculate).

I'm assuming they have some standard, or maybe there's an SAE one, that states testing at a certain temp in, internal flow, ambient temp, external flow, lighting (radiation), mounting (conduction), etc...
Click to expand...

i was offering to do the calculations using STP(68* F, 14.7 psi). so everything here would be under STP conditions.

so some questions here to ask.

1. what's the max PSI out of the primary. (We can roughly calculate outlet temp this way using STP)

2. what's the efficiency of the A/W interstage cooler (most manufacturers will market this number, even though it will be ball park)

3. whats the max psi out of the secondary(calculated using the outlet temp of the a/w interstage cooler)

i think velocity and turbulence can be calculated using SCFM of the turbo

all this is standard and theoretical.
 
STP stands for standard temperature and pressure. Which most consider 32* F. when in a lab setting.

Or at least I think that's what Fondler was meaning. ?

Anyways keep up the good talking, I'm still weighing my options.
 
Many different variants of STP. The one I'm using is 68* F and 1 atmosphere(14.7)
 
ok, so lets do some pretend math.(not going to include all the formulas because thats a lot to type)

STP @ 68*F - compressor efficiency of 70%

so at 30 psi primary, outlet temp = 381* F

lets assume 75% a/w intercooler = 95*F

now 95 inlet temp to secondary, 30 more psi to get to our desired 60 psi and the outlet temp = 607* F

throw it through another a/w at 75% = 151* into the engine.

my head hurts...
 
I run a type "52" as an interstage cooler, then a BD air/air after the secondary. In my system depending on the boost, the 52 is ~75% efficient and the BD is ~85%.

The water runs through the IC, then through a radiator with dual fans, then through a 5 gal tank, that I can add ice if desired. I used a 2000gpm Surflo livewell pump mainly due to the connections available over a bilge pump.

Couple of things... The system is heavy, over 100lbs. The ice doesn't last long. Pour in 20lbs when I'm a few cars back from staging, and the temp gauge shows it's already melted by the starting line. The cooler still helps a lot though.
 
What is your IAT's, if you have them monitored?

I understand the point of the extra weight. I'm not rocking some crazy amount of HP with a VE so I'm making a desperate attempt to give it the best chance it can to make some power.
 
smokinVE said:
What is your IAT's, if you have them monitored?

I understand the point of the extra weight. I'm not rocking some crazy amount of HP with a VE so I'm making a desperate attempt to give it the best chance it can to make some power.
Click to expand...

I only have 4 temp probes, and a so far just a few passes on it. So I have not measured the he IAT yet. Hopeful to do some real testing when the track opens.

My main reasons for installing it, were to help not blow as many silicone couplings, and to maybe run a smaller compressor on the secondary. So far, so good on the couplings. Need to get in some more full passes to tell on the secondary.
 
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