[SOCAL.M6.ZLE]

Originally Posted by Joshinator99

Oh snap! GPM and temp would be amazing… hint hint..

I agree... I already do temp and pressure before and after the blower, so I can monitor the effectiveness of the system in real time using the iDash. Unfortunately the flow meter is in the fender so I only use it when testing changes in the system.

Banks said the flow meter is lower on the list, but its on the list and expected by the end of the year... There are some aftermarket ones that might work in the interim... need to test.

[SpeZ]

Originally Posted by swisstyphoon

According to this document, if you run the Pierburg CWA pump on a constant 12V without PWM modulation, it will go into 'Notlauf' (emergency mode) and operate at approximately 95% of its maximum speed.

Good one.
Although 5% may not be a lot for me.
Within next weeks I can finally test drive and will check temperatures.
In the future I may build a control unit with arduino to be able to run it at max. speed.
When I was bleeding the system, I could definetly notice a gain in flow.
With the coolant resevoir cap off, coolant was splashing out.
If I'd had to guess, it was like 10-20% faster

[Joshinator99]

Originally Posted by SpeZ

Good one.
Although 5% may not be a lot for me.
Within next weeks I can finally test drive and will check temperatures.
In the future I may build a control unit with arduino to be able to run it at max. speed.
When I was bleeding the system, I could definetly notice a gain in flow.
With the coolant resevoir cap off, coolant was splashing out.
If I'd had to guess, it was like 10-20% faster

95% flow vs 100% flow will not be readily visible and difference won’t result in any meaningful reduction in performance. If that pump isn’t adequate for your system at 95%, then it wasn’t the right pump to begin with.

[SOCAL.M6.ZLE]

This is a great topic that I plan to do more testing on specific to the LT4. I think common logic understands that faster is not better past a certain point (undefined currently). I think it's clear that the most effective "cooling mods" are the ones that add capacity and surface area. Even at the same flow rate, there will be better heat transfer. too slow of a coolant flow will prevent efficient BTU transfer.... but too fast will also. There is a sweet spot which I believe is currently undefined. My guess is that it's somewhere between 5-6 GPM. Here is a clip from the flex-a-lite;

"Faster is not better when it comes to engine coolant flow rate. The purpose of a radiator is to support heat transfer, which is a time-dependent process. As Flex-a-Lite explains, to move the heat from one medium to another (engine to coolant to radiator to atmosphere), the coolant has to remain in contact with a surface for heat transfer to take place. Moving fluid too quickly through an area can result in laminar flow, where the fluid forms layers. The layer closest to the surface moves slower than layers farther away from the surface. When this occurs, the layers act as insulators and the capacity to transfer heat is diminished"

I am not sharing this to say that the CWA150 is not a beneficial modification... I do not know yet, and have not tested it yet on our system, but I have one, and plan to test more to measure flow, and pressure changes... as well as real world IAT.3 temps. Just wanted to contribute to the conversation.... and would love to see your GPM flow rate, although I know purchasing and installing the flow meter is very inconvenient. I will, and will share my data.

[Joshinator99]

Originally Posted by SOCAL.M6.ZLE

This is a great topic that I plan to do more testing on specific to the LT4. I think common logic understands that faster is not better past a certain point (undefined currently). I think it's clear that the most effective "cooling mods" are the ones that add capacity and surface area. Even at the same flow rate, there will be better heat transfer. too slow of a coolant flow will prevent efficient BTU transfer.... but too fast will also. There is a sweet spot which I believe is currently undefined. My guess is that it's somewhere between 5-6 GPM. Here is a clip from the flex-a-lite;

"Faster is not better when it comes to engine coolant flow rate. The purpose of a radiator is to support heat transfer, which is a time-dependent process. As Flex-a-Lite explains, to move the heat from one medium to another (engine to coolant to radiator to atmosphere), the coolant has to remain in contact with a surface for heat transfer to take place. Moving fluid too quickly through an area can result in laminar flow, where the fluid forms layers. The layer closest to the surface moves slower than layers farther away from the surface. When this occurs, the layers act as insulators and the capacity to transfer heat is diminished"

I am not sharing this to say that the CWA150 is not a beneficial modification... I do not know yet, and have not tested it yet on our system, but I have one, and plan to test more to measure flow, and pressure changes... as well as real world IAT.3 temps. Just wanted to contribute to the conversation.... and would love to see your GPM flow rate, although I know purchasing and installing the flow meter is very inconvenient. I will, and will share my data.

Whoever wrote that does not do fluid dynamics for a living, that’s for sure. Laminar flow results from moving the water too SLOWLY, since you lose turbulence. And in that situation their description is correct on that the outer layer of water “insulates” the moving water from the heat exchanger.

Now that said, they are correct that moving the water too fast can hurt since you’re not giving the water adequate dwell time on the heat exchangers for the heat to actually transfer. The example I give my guys is sort of like a train station…if the train is flying by the loading dock, no one is getting on or off the train haha!

I’m going to say it yet again: capacity does NOTHING for cooling. It’s a band aid for inadequate heat exchanger units and/or improper flow. Period. Now if you know you’re not upgrading your blower bricks or heat exchanger, and more water capacity can help that, then by all means go for it. Interchiller is in the same boat…it won’t cool fast enough at WOT so you need some capacity, so I get it. But E85 is superior to a Interchiller and renders it unnecessary since alcohol needs heat to properly vaporize.

Back to capacity: I run zero capacity in my system and enjoy IATs that drop as the run goes on…because I have good heat exchangers and good flow. As I continue to turn the power up, I will probably make more improvements on that front using Gabe’s stuff. If I reach a point in power output where larger heat heat exchangers don’t keep up, then I’ll begrudgingly add capacity. But that’s extra weight so it’s a worst case scenario so I’ll avoid that as long as possible.

[RobZL1]

Originally Posted by Joshinator99

Whoever wrote that does not do fluid dynamics for a living, that’s for sure. Laminar flow results from moving the water too SLOWLY, since you lose turbulence. And in that situation their description is correct on that the outer layer of water “insulates” the moving water from the heat exchanger.

you got to it before I did. I read that and was like, whuuut? uhhh, nope!

[SOCAL.M6.ZLE]

Originally Posted by Joshinator99

Whoever wrote that does not do fluid dynamics for a living, that’s for sure. Laminar flow results from moving the water too SLOWLY, since you lose turbulence. And in that situation their description is correct on that the outer layer of water “insulates” the moving water from the heat exchanger.

Now that said, they are correct that moving the water too fast can hurt since you’re not giving the water adequate dwell time on the heat exchangers for the heat to actually transfer. The example I give my guys is sort of like a train station…if the train is flying by the loading dock, no one is getting on or off the train haha!

I’m going to say it yet again: capacity does NOTHING for cooling. It’s a band aid for inadequate heat exchanger units and/or improper flow. Period. Now if you know you’re not upgrading your blower bricks or heat exchanger, and more water capacity can help that, then by all means go for it. Interchiller is in the same boat…it won’t cool fast enough at WOT so you need some capacity, so I get it. But E85 is superior to a Interchiller and renders it unnecessary since alcohol needs heat to properly vaporize.

Back to capacity: I run zero capacity in my system and enjoy IATs that drop as the run goes on…because I have good heat exchangers and good flow. As I continue to turn the power up, I will probably make more improvements on that front using Gabe’s stuff. If I reach a point in power output where larger heat heat exchangers don’t keep up, then I’ll begrudgingly add capacity. But that’s extra weight so it’s a worst case scenario so I’ll avoid that as long as possible.

Thanks for jumping in Josh, this is a great topic! I was under the impression that laminar flow actually helped transfer heat between the layers of flow from the slowest moving nearest the heat source to the center of flow which is the fastest... similar to blood flow in the body.

[Joshinator99]

Originally Posted by RobZL1

you got to it before I did. I read that and was like, whuuut? uhhh, nope!

Originally Posted by SOCAL.M6.ZLE

Thanks for jumping in Josh, this is a great topic! I was under the impression that laminar flow actually helped transfer heat between the layers of flow from the slowest moving nearest the heat source to the center of flow which is the fastest... similar to blood flow in the body.

Negative my friend! TURBULENCE is the word of the day. So you need enough flow to keep water temperature effective across the supercharger brick (too slow of a flow rate means the water heats up too much in the supercharger brick and makes it less effective in cooling the charge…(ie 150 degree water does a worse job cooling the air than 100 degree water), enough turbulence to make sure the water is scrubbed across the heat exchanger for max heat transfer, and flow that is slow enough to allow for the actual heat transfer (allowing you to dump heat out of the water using your heat exchangers). It’s definitely a balancing act.

In other words, you’re balancing this flow rate so that you keep a reasonable temperature differential across the supercharger brick, say 10-20 degrees…and then you have adequate flow and heat exchanger surface area to scrub that 10-20 degrees out the other end. If you pump too fast the differential shrinks too much (maybe only 5 degrees) so now you’re not absorbing or rejecting enough BTUs. If you pump too slow, the differential jumps up to maybe 40 or more degrees so now you have brick temps that aren’t useful… 150 degree water is pretty useless since heat transfer is directly dependent and proportional to temperature difference! So if your supercharger is spitting out 200 degree air, then 100 degree water will pull heat from the air charge faster than 150 degree water will…that’s a point that seems obvious though.

Hope that helps! But measuring flow and temperatures before & after the brick (and heat exchanger if possible) can help you understand a lot about what’s up. I am lazy though and just upgrade everything to the biggest/best I can find and then look at final results haha

[SOCAL.M6.ZLE]

Originally Posted by Joshinator99

Negative my friend! TURBULENCE is the word of the day. So you need enough flow to keep water temperature effective across the supercharger brick (too slow of a flow rate means the water heats up too much in the supercharger brick and makes it less effective in cooling the charge…(ie 150 degree water does a worse job cooling the air than 100 degree water), enough turbulence to make sure the water is scrubbed across the heat exchanger for max heat transfer, and flow that is slow enough to allow for the actual heat transfer (allowing you to dump heat out of the water using your heat exchangers). It’s definitely a balancing act.

In other words, you’re balancing this flow rate so that you keep a reasonable temperature differential across the supercharger brick, say 10-20 degrees…and then you have adequate flow and heat exchanger surface area to scrub that 10-20 degrees out the other end. If you pump too fast the differential shrinks too much (maybe only 5 degrees) so now you’re not absorbing or rejecting enough BTUs. If you pump too slow, the differential jumps up to maybe 40 or more degrees so now you have brick temps that aren’t useful… 150 degree water is pretty useless since heat transfer is directly dependent and proportional to temperature difference! So if your supercharger is spitting out 200 degree air, then 100 degree water will pull heat from the air charge faster than 150 degree water will…that’s a point that seems obvious though.

Hope that helps! But measuring flow and temperatures before & after the brick (and heat exchanger if possible) can help you understand a lot about what’s up. I am lazy though and just upgrade everything to the biggest/best I can find and then look at final results haha

Great feedback Josh, that makes sense... I understand turbulence would be a negative effect, I was just saying that I dint not think laminar flow was necessarily a bad thing. Love your lazy comment BTW. Sounds like it's working so far!

A few things that I have found with my system, is that the extra volume helps alot. Granted I am a roll race guy, it's cool watching the HX coolant temps at the end of a 40-150 pull put a 60F difference between the incoming coolant and outgoing coolant, but because that 120-130F water instantly mixes with 2 gallons in the fender tank, before going through 3 HX, it very hard to actually raise the inlet HX coolant temps on the street.

Talking with RAVI from CSF today, he couldn't believe we have unlocked a 50% increase in flow by removing the main restrictions. About the pump, it was his opinion that the CWA150 pump should be a benefit. Although it's relative to vehicle speed, his guess was that the sweet spot would be closer to 7GPM, but would need to test. I haven't looked into it yet, but I need to see if HPT and control the PWM on the CWA150. Ravi was explaining that the new BMW's use variable pressure HX pumps, because you want a slower flow rate at lower speeds, and a higher flow rate at higher speeds. He didnt know the flow rate but I guess Nascar runs at 40psi + for the cooling systems based on the higher speeds, where as the OEM pump on my set up sees around 13.5psi on the cold side and 19psi on the hot side...

[SpeZ]

So a small update.
I actually got no clue, but when I run the pump and completly fill my resevoir, close the lid and shut off the pump a big amount of fluid squirts out of the 16 PSI valve cap.
My callaway supercharger sits higher than the resevoir.
So if the pump turns off, fluid drains into the resevoir + with higher flow because of the pump which actually triggers the overpressure valve.

I can't really tell, if the valve is maybe broken or not.
With HPTuners I could not notice a real difference in temperatures of the MAT.
Maybe it can't because it's not meassured, only calculated by the ECM as far as I know.
I still run high amount of glykol which directs heat worse.

[Joshinator99]

Originally Posted by SpeZ

So a small update.
I actually got no clue, but when I run the pump and completly fill my resevoir, close the lid and shut off the pump a big amount of fluid squirts out of the 16 PSI valve cap.
My callaway supercharger sits higher than the resevoir.
So if the pump turns off, fluid drains into the resevoir + with higher flow because of the pump which actually triggers the overpressure valve.

I can't really tell, if the valve is maybe broken or not.
With HPTuners I could not notice a real difference in temperatures of the MAT.
Maybe it can't because it's not meassured, only calculated by the ECM as far as I know.
I still run high amount of glykol which directs heat worse.

Does the car ever see freezing or extreme high temps (road course etc)? In virtually all cases 30% ethylene glycol to 70% distilled water is fine. I run straight water in my intercooler with a bottle of Redline Water Wetter but it never sees winter conditions.

Your reservoir usually has a fill line that you fill to…water is non-compressible so you cannot fill it right to the top, or any heat will cause it to pop the pressure relief built into the reservoir cap…

[SpeZ]

Originally Posted by Joshinator99

Does the car ever see freezing or extreme high temps (road course etc)? In virtually all cases 30% ethylene glycol to 70% distilled water is fine. I run straight water in my intercooler with a bottle of Redline Water Wetter but it never sees winter conditions.

Your reservoir usually has a fill line that you fill to…water is non-compressible so you cannot fill it right to the top, or any heat will cause it to pop the pressure relief built into the reservoir cap…

Yup it does see freezing temps.
I will have to wait around 4 weeks for warmer weather and then change all my fluids.
15W50 Oil, Destilled water + water wetter for coolant.
Last year I used 100% destilled water during summer.

I didn't find a fill line.
Callaway instructions say the following:
"fill the reservoir tank completely, replace the cap and turn the vehicle off."

The thing is, as soon as the pump starts, fluid level decreases inside the resevoir because it fills the entire system (top of the supercharger).
Because of the increased flow it splashes into the resevoir which is maybe 1/4 full when the pump runs and creates air bubbles which some of them get probably sucked into the system.

[SpeZ]

So when running the pumpe with open resevoir I can clearly hear sometimes the pump running like 2x the speed and then goes back to normal. The fluid level in the resevoir decreases also for a second when that happens.
I am 100% sure it is because of cavitaion.
This video matches it perfectly


I still run all the stock hoses, but the pump seems to be too strong, it tries to pump more fluid than it gets.
Tomorrow I will try to change the hose to the intake from the pump.
It's the factory callaway hose which is like only a 45°gradient from resevoir to pump and at the pump it is 90° angled.
So it might actually suck all the fluid at once which sits vertically in the hose up to the 90° and then fluid in the nearly horizontally hose...

[Rapid_blue_zl1_22]

WTF happened here? Can someone delete this dudes comments and ban him?