The Great Intercooler Water Pump Test

Department Of Boost

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You could make arguments both directions. I'd run the bypass. There is no way of telling if you're having cavitation issues unless you put some clear tubing in after the pump so you can see it.
 

1950StangJump$

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You could make arguments both directions. I'd run the bypass. There is no way of telling if you're having cavitation issues unless you put some clear tubing in after the pump so you can see it.

Hey, I was putting thought into this, and I can see now how the bypass can't hurt flow even if not needed.

But correct me if I'm wrong, but the downside with the bypass will be that you can't tell positively if the pump is working, right? With a bypass in place, the tank becomes a true overflow and de-gas, so it will look like the engine coolant overflow . . . no visible movement in it per sae. Instead, the level will just climb and lower with heat just like the engine coolant (but not as much since it doesn't get as hot as engine coolant).

So, if the pump jams up with air, you wouldn't know until it your intake temp gauge climbed. With no bypass, there would be obvious flow in the tank, and you would know if that stopped that there's a problem. Am I right?
 

Department Of Boost

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Hey, I was putting thought into this, and I can see now how the bypass can't hurt flow even if not needed.

But correct me if I'm wrong, but the downside with the bypass will be that you can't tell positively if the pump is working, right? With a bypass in place, the tank becomes a true overflow and de-gas, so it will look like the engine coolant overflow . . . no visible movement in it per sae. Instead, the level will just climb and lower with heat just like the engine coolant (but not as much since it doesn't get as hot as engine coolant).

So, if the pump jams up with air, you wouldn't know until it your intake temp gauge climbed. With no bypass, there would be obvious flow in the tank, and you would know if that stopped that there's a problem. Am I right?
The water still flows through the tank. Just slower/less volume.
 

eighty6gt

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Here's the bypass I built, I suspect it's pretty cheap. Those are coolant-rated tees and I used heat shrink hose clamps. There's a restrictor on the path that goes up to the degas (the fox body heater core part!)

With the way I have the lines run the degas has a direct run into the pump inlet. Before I had a loop which made priming annoying, so I like this system for flow, priming, etc... Nice gentle waves in the degas bottle, and I went to a standard GT500 unit instead of the VMP enormous one I had before. The 2013 HE has plenty of extra room for coolant volume. The system functions spectacularly.

IMG_20180903_151930.jpg
 

Pentalab

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The oem 13/14 GT-500 de-gas is a tiny little thing. The de-gas on the 2010 roush M90 is huge by comparison. From output of IC, it goes to top of de-gas. Bottom of de-gas goes to input of pump. Output of pump goes to bottom right corner of Roush 18" tall x 21" wide HE. Top left of HE goes back to input of IC...completing the loop. I can just notice the coolant moving in the de-gas..but that's with oem Bosch pump. I estimate there is perhaps 2 gals in the loop. At 4 gpm, it would take a full 30 secs to circulate the coolant..once.
With just 5.8 psi, and 70-85 deg F outside ambient temps, it's a non issue with 94 octane.
 

1950StangJump$

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With the way I have the lines run the degas has a direct run into the pump inlet.

View attachment 69123

Seems like, for efficiency of flow/cooling, you'd want the line from the IC to the pump to be the most direct, with the degas being off to the side. In other words, no right had turns from the IC to the pump, but instead have 90 degree turns in the 'T' connections be for the degas supply and return lines . . . like the picture DOB posted.

As for priming, I think it would be important to have the main line continue downward from the IC to the pump, with the supply line 'T' to the degas being slightly higher than the 'T' return from the degas. Again, like DOB pictured.

This would encourage all air to float upward to the degas where it would be carried away harmlessly. It would still take longer to purge air than with no bypass, but I think still okay.
 

DiMora

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Seems like, for efficiency of flow/cooling, you'd want the line from the IC to the pump to be the most direct, with the degas being off to the side. In other words, no right had turns from the IC to the pump, but instead have 90 degree turns in the 'T' connections be for the degas supply and return lines . . . like the picture DOB posted.

As for priming, I think it would be important to have the main line continue downward from the IC to the pump, with the supply line 'T' to the degas being slightly higher than the 'T' return from the degas. Again, like DOB pictured.

This would encourage all air to float upward to the degas where it would be carried away harmlessly. It would still take longer to purge air than with no bypass, but I think still okay.

There are actually four ways to plumb, depending on whether you run an ice-box or not.

Street car (no ice)...you want the pump to push water into the heat exchanger (ALWAYS fill the heat exchanger from the bottom)

One way for street car:

Pump outlet->heat exchanger bottom inlet ->intercooler->degas fill inlet ->pump inlet

A variation is:

Degas outlet -> pump ->intercooler->heat exchanger->degas inlet

The only difference between the above two is whether or not the pump goes between the degas and the heat exchanger (first one) or the degas and the intercooler (second one).

For a pure race car or a street car where you run ice on race days, you can plumb either permantly or temporarily to go:

Ice box exit-> Pump inlet -> intercooler ->heat exchanger bottom inlet->ice box inlet

That routing works well when you have room to mount the coolant pump right on the firewall between a battery box ice tank and the intercooler inlet

Variation:

Ice box exit ->intercooler ->pump->heat exchanger bottom inlet->ice box inlet

That routing works well when you mount the pump near the heat exchanger...usually below the windshield washer tank like Saleen does or above the left front wheel wheel inside the splash guard like Roush does. Shelby's often mount the pump along the top of the heat exchanger.

The reason for the above two flow paths is to get the ice water going straight to the intercooler without warming in the heat exchanger
 
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1950StangJump$

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So, got my GT500 pump kit from DOB installed on my 4.6 with Kenne Bell and VMP triple pass HE. Used the bypass option for the pump. Pump is super quiet.

I was surprised to see no movement in the reservoir, and I thought at first the pump was air-locked. Right now, I have the system such that it runs down hill from the IC to get to the pump. In between, it tees off for both the supply and return lines to the reservoir. Both points on the reservoir represent the highest points in the system - fluid actually has to climb uphill through two feet of hose to get to the supply entrance of the reservoir). So, maybe the fluid is taking the path of least resistance (bypassing the reservoir), especially considering all the restrictions with the KB? I also have the reservoir tank pretty full (higher than the return line entry), so it is possible there is movement under the surface.

I took it for a spirited run. It was 60 degrees out. AITs stayed 100-110. Would climb to 115ish under boost or closed throttle, then quickly come back down when light on the throttle. So I guess its working, though I did wonder if the cool air being sucked into the intake could keep it that cool even if the pump was locked up. Jason (DOB) says no.

Note, the fluid in the reservoir still felt very cool to the touch even after the run. The engine coolant, in contrast, was HOT.
 

DiMora

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So, got my GT500 pump kit from DOB installed on my 4.6 with Kenne Bell and VMP triple pass HE. Used the bypass option for the pump. Pump is super quiet.

I was surprised to see no movement in the reservoir, and I thought at first the pump was air-locked. Right now, I have the system such that it runs down hill from the IC to get to the pump. In between, it tees off for both the supply and return lines to the reservoir. Both points on the reservoir represent the highest points in the system - fluid actually has to climb uphill through two feet of hose to get to the supply entrance of the reservoir). So, maybe the fluid is taking the path of least resistance (bypassing the reservoir), especially considering all the restrictions with the KB? I also have the reservoir tank pretty full (higher than the return line entry), so it is possible there is movement under the surface.

I took it for a spirited run. It was 60 degrees out. AITs stayed 100-110. Would climb to 115ish under boost or closed throttle, then quickly come back down when light on the throttle. So I guess its working, though I did wonder if the cool air being sucked into the intake could keep it that cool even if the pump was locked up. Jason (DOB) says no.

Note, the fluid in the reservoir still felt very cool to the touch even after the run. The engine coolant, in contrast, was HOT.

I would temporarily disconnect the bypass line to make sure fluid is circulating through the degas and the pump is primed.

You don’t want your pump running dry; that will destroy it.

With the above stated; it sounds like it is working based on your IAT’s.
 

1950StangJump$

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I would temporarily disconnect the bypass line to make sure fluid is circulating through the degas and the pump is primed.

You don’t want your pump running dry; that will destroy it.

With the above stated; it sounds like it is working based on your IAT’s.

Thanks. I dread that idea because of the mess.

I do have a switch on the pump and HE fans, so I could cut power to it while driving and see what AITs do.

EDIT: At one point, I did loosen the hose at the exit of the HE while the pump was running ..... it shot fluid out.
 

DiMora

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Thanks. I dread that idea because of the mess.

I do have a switch on the pump and HE fans, so I could cut power to it while driving and see what AITs do.

Well that (switch off) would tell you for sure. IAT’s will rise rapidly with no coolant flow. Drive at a steady speed and cycle the switch OFF, IAT’s should rise; then while still holding speed steady, turn it ON and IAT’s should immediately drop.
 

1950StangJump$

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Just saw your edit. If it shot fluid out; you’re good.

Dumb question .... when it’s cold out ..... AITs will go crazy with no coolant flow?

If it was 60 degrees, I’m imagining that air being sucked into the CAI cone while moving was 45ish. Just wondering if it is at all possible to keep the AITs that cool with only the intake air.
 

DiMora

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Dumb question .... when it’s cold out ..... AITs will go crazy with no coolant flow?

If it was 60 degrees, I’m imagining that air being sucked into the CAI cone while moving was 45ish. Just wondering if it is at all possible to keep the AITs that cool with only the intake air.

My rise (air filter air temp) compared to IAT is usually between 23 and 29 degrees. That is with a Steeda Triple-pass and a Meziere 20 GPM pump which is actually flowing 3.5GPM.

My own epic upgrade is in progress!

2v2EAknNnxUQZjg.jpg
 

1950StangJump$

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My rise (air filter air temp) compared to IAT is usually between 23 and 29 degrees. That is with a Steeda Triple-pass and a Meziere 20 GPM pump which is actually flowing 3.5GPM.

My own epic upgrade is in progress!

2v2EAknNnxUQZjg.jpg

Yea mean 23-29 degree AITs above ambient with the system running? I'm wondering if it is possible to keep AITs down when the air is cool but the pump is NOT running.

Just thinking out loud -- wondering whether there was any chance my AITs could have stayed 100-115 with yesterday's 60 degree temps if the pump had locked up.
 

DiMora

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Yea mean 23-29 degree AITs above ambient with the system running? I'm wondering if it is possible to keep AITs down when the air is cool but the pump is NOT running.

Just thinking out loud -- wondering whether there was any chance my AITs could have stayed 100-115 with yesterday's 60 degree temps if the pump had locked up.

Yes, those temps are with the system running. Not running I would think you would see crazy high temps...170-190.

If it shot water out of the hose the pump is not locked up. Did it come out with force (spray) and not just a leak?
 

1950StangJump$

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Yes, those temps are with the system running. Not running I would think you would see crazy high temps...170-190.

If it shot water out of the hose the pump is not locked up. Did it come out with force (spray) and not just a leak?
Leak with the pump not running, force when it was. Yea, I’m confident I’m good to go .... just made me wonder and wanted to learn
 

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