A better understanding of the I/C system
Thread Starter
|
Senior Member
Joined: Feb 2008
Posts: 4,508
Likes: 30
From: VA
A better understanding of the I/C system
After some thinking I decided to check the rate that water flows thru a factory i/c pump. I had taken mine apart and had to reassemble it to get started. That was a Mensa test for sure.
To simulate the friction of the cars water circuit; I used the stock heat exchanger and my LET heat exchanger since I removed them both. All together I have an expansion tank, the pump and two h/e coils in a loop. See the photos for an idea of it all assembled. [I am using the 2 square foot h/e on my car that I put together for testing, and like.]
Well as things go it was interesting and very informative to me. I used a 100-amp hour 12-volt battery from my solar panel system. The 60% antifreeze [same for all tests] flow was a terrible 1.6 gallons per minute (GPM). The pump was working correctly and I set about to understand this very low flow issue. To check things I finally pulled the factory h/e out and just circulated coolant from the pump to the tank and thru the LET h/e………….ZOOOOOM the flow jumped up to over 5 GPM and that pegged my flow meter. The water is totally moving now but why? My h/e was very restricted and after I flushed it twice from both directions I tried to blow thru it (dry). The factory h/e is Massively restrictive and it is easy to see this by looking into the pipe fitting ends.
The factory h/e is terrible and has VERY LIMITED cooling capacity. On my soapbox, I have been testing the I/c circuit a bunch and the stock h/e is too small, too restrictive and worthless as almost NO air gets thru it due to its mounting and DISTANCE FROM the A/C coil. The motion of the car is feeble when it comes to moving air thru the core. The motion of the car pushes air into the grill, which pressurizes the radiators area, but the air pressures effect on the front of the h/e is reduced by the reflected pressure on the rear side caused by the restriction of the A/C core behind it. Air mostly goes thru the A/C core and radiator as it continues on toward the engine and the lower air pressure areas beneath the car. Phew that’s a lot of ideas.
The engine fan cannot do much because it is so far from the h/e core that no ‘suction’ leftover to pull the air into the core for cooling. I first noted this by measuring the differential temperature between the water coming out of the I/C and the water returning to it. Under a GO the best that I could get was 6 degrees even with the better flowing LET H/E. I got 6 degrees of water-cooling in one pass of the water, Yikes that’s terrible; it’s not a flow problem because the flow with the LET was about 3.7 GPM.
I tried to add 4 fans (TO MY LET) if you remember that posting, it did not get enough air and the fans were rated at 100 CFM per fan. For a meaningful change I designed/built and placed a BIG H/E adjacent to the A/C core with a ¼” air gap.
I had hoped to see up to a 20-degree change in the water temperature as it passed thru the new H/E due to its size and MOUNTING IN FRONT OF THE ENGINE RADIATOR so that it could breath.
TAA DAAA on my first GO I saw a peak differential of 43 degrees on a 90-degree day though the ambient should not affect the differential much. That was about 179-degree water out of the I/C and 130-degree returning water to it, yes I got cooling. I had suffered under heat induced LIMP MODE engine protection several times in the heat with the car on an autocross track. Now I buzz around at 6000 most of the time in first gear and that builds heat but since the new H/E it’s all-cool, literally.
My Findings to date:
The stock H/E is bad and has too much restriction. It’s only located NEAR the airflow and has little to add to your performance.
The LET has MUCH bigger cross section to allow more airflow.
The LET is MUCH better water flow than stock (less restriction) about 3 to one. Try to blow thru a clean one OMG! Try the stocker Yikes.
To REALLY gain benefit, the LET H/E needs to be in the radiator air stream, as close to the A/C core as possible (¼”). This effort will generate a BETTER AIR PRESSURE DIFFERENTIAL ACROSS THE H/E, to promote the passage of MORE AIR. That’s better cooling.
I did try a NASCAR type of air tunnel from the LET to the radiator but most of the air bypassed it and passed thru the rest of the radiator instead. I publish the fails as well as the passes.
In my SRT-6 The coolant flow with the Johnson pump and LET H/E was 3.7 GPM
In my SRT-6 The coolant flow with the Johnson pump and my H/E was 3.1 GPM
My cooling changes (to Date)
My own design 180-degree stat (170 only for the summer months)
My BIGGER dual circuit H/E mounted to the A/C core area 2’ Square
Johnson pump though it’s similar to the stocker capacity
Insulated NW CAI ( Brian will discuss this I trust, Hee Hee )
Shielded exhaust header
LET Phenolic gaskets
Grill modifications to open it up
Fan speed up option for racing (330 ohm Resistor across temp sensor)
Iam getting ready to go to the track twice this weekend and hope to get more hard empirical data on the I/C cooling system. This will be a legal opportunity for me to get on it hard for about 45 – 60 seconds at a crack. To gather the data I have installed temporarily some digital thermometers to see the I/C operation, and of course I can not begin to see the results so I will be setting up my DVD camera to watch for me. Photos below FYI.
Weeeee Iam playing too much somebody stop me. ( Jim Carrey )
Photos
Test stand
Test stand again
Flow with Stock h/e and LET
Flow with JUST the LET core
Test instruments for camera
Flow with Stock h/e and LET again
180 stat reading on gauge
Flow testing
Reassembled stock pump
Toy just sold to high school buddy
To simulate the friction of the cars water circuit; I used the stock heat exchanger and my LET heat exchanger since I removed them both. All together I have an expansion tank, the pump and two h/e coils in a loop. See the photos for an idea of it all assembled. [I am using the 2 square foot h/e on my car that I put together for testing, and like.]
Well as things go it was interesting and very informative to me. I used a 100-amp hour 12-volt battery from my solar panel system. The 60% antifreeze [same for all tests] flow was a terrible 1.6 gallons per minute (GPM). The pump was working correctly and I set about to understand this very low flow issue. To check things I finally pulled the factory h/e out and just circulated coolant from the pump to the tank and thru the LET h/e………….ZOOOOOM the flow jumped up to over 5 GPM and that pegged my flow meter. The water is totally moving now but why? My h/e was very restricted and after I flushed it twice from both directions I tried to blow thru it (dry). The factory h/e is Massively restrictive and it is easy to see this by looking into the pipe fitting ends.
The factory h/e is terrible and has VERY LIMITED cooling capacity. On my soapbox, I have been testing the I/c circuit a bunch and the stock h/e is too small, too restrictive and worthless as almost NO air gets thru it due to its mounting and DISTANCE FROM the A/C coil. The motion of the car is feeble when it comes to moving air thru the core. The motion of the car pushes air into the grill, which pressurizes the radiators area, but the air pressures effect on the front of the h/e is reduced by the reflected pressure on the rear side caused by the restriction of the A/C core behind it. Air mostly goes thru the A/C core and radiator as it continues on toward the engine and the lower air pressure areas beneath the car. Phew that’s a lot of ideas.
The engine fan cannot do much because it is so far from the h/e core that no ‘suction’ leftover to pull the air into the core for cooling. I first noted this by measuring the differential temperature between the water coming out of the I/C and the water returning to it. Under a GO the best that I could get was 6 degrees even with the better flowing LET H/E. I got 6 degrees of water-cooling in one pass of the water, Yikes that’s terrible; it’s not a flow problem because the flow with the LET was about 3.7 GPM.
I tried to add 4 fans (TO MY LET) if you remember that posting, it did not get enough air and the fans were rated at 100 CFM per fan. For a meaningful change I designed/built and placed a BIG H/E adjacent to the A/C core with a ¼” air gap.
I had hoped to see up to a 20-degree change in the water temperature as it passed thru the new H/E due to its size and MOUNTING IN FRONT OF THE ENGINE RADIATOR so that it could breath.
TAA DAAA on my first GO I saw a peak differential of 43 degrees on a 90-degree day though the ambient should not affect the differential much. That was about 179-degree water out of the I/C and 130-degree returning water to it, yes I got cooling. I had suffered under heat induced LIMP MODE engine protection several times in the heat with the car on an autocross track. Now I buzz around at 6000 most of the time in first gear and that builds heat but since the new H/E it’s all-cool, literally.
My Findings to date:
The stock H/E is bad and has too much restriction. It’s only located NEAR the airflow and has little to add to your performance.
The LET has MUCH bigger cross section to allow more airflow.
The LET is MUCH better water flow than stock (less restriction) about 3 to one. Try to blow thru a clean one OMG! Try the stocker Yikes.
To REALLY gain benefit, the LET H/E needs to be in the radiator air stream, as close to the A/C core as possible (¼”). This effort will generate a BETTER AIR PRESSURE DIFFERENTIAL ACROSS THE H/E, to promote the passage of MORE AIR. That’s better cooling.
I did try a NASCAR type of air tunnel from the LET to the radiator but most of the air bypassed it and passed thru the rest of the radiator instead. I publish the fails as well as the passes.
In my SRT-6 The coolant flow with the Johnson pump and LET H/E was 3.7 GPM
In my SRT-6 The coolant flow with the Johnson pump and my H/E was 3.1 GPM
My cooling changes (to Date)
My own design 180-degree stat (170 only for the summer months)
My BIGGER dual circuit H/E mounted to the A/C core area 2’ Square
Johnson pump though it’s similar to the stocker capacity
Insulated NW CAI ( Brian will discuss this I trust, Hee Hee )
Shielded exhaust header
LET Phenolic gaskets
Grill modifications to open it up
Fan speed up option for racing (330 ohm Resistor across temp sensor)
Iam getting ready to go to the track twice this weekend and hope to get more hard empirical data on the I/C cooling system. This will be a legal opportunity for me to get on it hard for about 45 – 60 seconds at a crack. To gather the data I have installed temporarily some digital thermometers to see the I/C operation, and of course I can not begin to see the results so I will be setting up my DVD camera to watch for me. Photos below FYI.
Weeeee Iam playing too much somebody stop me. ( Jim Carrey )
Photos
Test stand
Test stand again
Flow with Stock h/e and LET
Flow with JUST the LET core
Test instruments for camera
Flow with Stock h/e and LET again
180 stat reading on gauge
Flow testing
Reassembled stock pump
Toy just sold to high school buddy
Last edited by waldig; 08-28-2008 at 05:00 PM.
Senior Member
Joined: May 2008
Posts: 10,395
Likes: 111
From: Cincinnati ( Delhi )
Re: A better understanding of the I/C system
First off, I don't own an SRT, but what you are doing is interesting. Being able to have the resources and first hand experience of your findings is great. Keep up the good work.
I did similar work on my S10 a couple years ago to eliminate the factory belt driven cooling fan. Once I got my electric fan and the correct controls worked out, its been working great ever since.
James
I did similar work on my S10 a couple years ago to eliminate the factory belt driven cooling fan. Once I got my electric fan and the correct controls worked out, its been working great ever since.
James
Senior Member
Joined: Jan 2008
Posts: 5,180
Likes: 8
From: North Plains, OR
Thread Starter
|
Senior Member
Joined: Feb 2008
Posts: 4,508
Likes: 30
From: VA
Re: A better understanding of the I/C system
To improve my car I have the stock I/C fed by the johnson pump using ONLY my double H/E.
You should not consider adding another H/E in series with the restrictive factory unit. It is enough to pop your ears trying to blow your breath the DRY core. The LET is easy to blow thru and its good for that, its only failing is that it is durn near impossible to get enough air flow thru it to use the core to its potential.
FYI Iam thinking of getting a Summit aluminum radiator ( one core ) to use as it is like 24 " wide and thin enough to fit. Problem here is the inlet and outlet piping, cause I would like to fab up a simple change that others without my TIG welder could reproduce, sorta like a challange you know.
Its kinda like using petroleum jelly to improve your sex life, you just have to remember to put it on the door ****,
to help keep the kids out.
You should not consider adding another H/E in series with the restrictive factory unit. It is enough to pop your ears trying to blow your breath the DRY core. The LET is easy to blow thru and its good for that, its only failing is that it is durn near impossible to get enough air flow thru it to use the core to its potential.
FYI Iam thinking of getting a Summit aluminum radiator ( one core ) to use as it is like 24 " wide and thin enough to fit. Problem here is the inlet and outlet piping, cause I would like to fab up a simple change that others without my TIG welder could reproduce, sorta like a challange you know.
Its kinda like using petroleum jelly to improve your sex life, you just have to remember to put it on the door ****,
to help keep the kids out.
Joined: May 2008
Posts: 118
Likes: 0
From: Voorhees, NJ
Re: A better understanding of the I/C system
Great R&D! Keep it up. You are really becoming the cooling guru.
This whole test really sparks my curiosity of one particular aspect. Maybe you've considered this already, but many people are running the higher flowing Johnson pumps (still waiting for mine
). When they do, they are hooking them up to the same small gauge crap wires that the factory pump is hooked up to. Sure, you're still getting 12+ volts, but how much current can they support. Do you think we might benefit from basically "hot wiring" the pump to the battery with heavier gauge wires and using the factory wires to control the pump via an additional relay? This trick is sometimes used to increase the current to the fuel pump on modified cars, subsequently increasing flow. Do you think you could incorporate this into your testing?
This whole test really sparks my curiosity of one particular aspect. Maybe you've considered this already, but many people are running the higher flowing Johnson pumps (still waiting for mine
). When they do, they are hooking them up to the same small gauge crap wires that the factory pump is hooked up to. Sure, you're still getting 12+ volts, but how much current can they support. Do you think we might benefit from basically "hot wiring" the pump to the battery with heavier gauge wires and using the factory wires to control the pump via an additional relay? This trick is sometimes used to increase the current to the fuel pump on modified cars, subsequently increasing flow. Do you think you could incorporate this into your testing?
Senior Member
Joined: Jan 2008
Posts: 5,180
Likes: 8
From: North Plains, OR
Re: A better understanding of the I/C system
Okay. I'll have to go back and start searching for a bigger coil/radiator to use for the HE. I am moving the horns this weekend and already opened up the grill to get all the air possible. There is a plus to putting the HE coil in front of the radiator with the wide open grill. It will be protecting my radiator from flying rocks!!! Only a minor annoyance if the HE springs a leak.
MikeR
MikeR
Re: A better understanding of the I/C system
Originally Posted by waldig
To check things I finally pulled the factory h/e out and just circulated coolant from the pump to the tank and thru the LET h/e………….ZOOOOOM the flow jumped up to over 5 GPM and that pegged my flow meter. The water is totally moving now but why? My h/e was very restricted and after I flushed it twice from both directions I tried to blow thru it (dry). The factory h/e is Massively restrictive and it is easy to see this by looking into the pipe fitting ends.
Perhaps your factory HE is clogged or damaged.
Senior Member
Joined: Nov 2007
Posts: 1,225
Likes: 0
Re: A better understanding of the I/C system
Originally Posted by BrianBrave
Woody - I have two factory HE's in my backyard - I read this post and went out back with and air-blower and gave each one a squirt - the one that was shipped to me was dry and blew air no problem. The other was the HE I removed my SRT and I guess I didn't drain it cause it shot coolant up the wall..
Perhaps your factory HE is clogged or damaged.
Perhaps your factory HE is clogged or damaged.
Re: A better understanding of the I/C system
Originally Posted by 240M3SRT
Were you using compressed air or blowing with your mouth like he was?
Originally Posted by BrianBrave
Woody - I have two factory HE's in my backyard - I read this post and went out back with and air-blower and gave each one a squirt - the one that was shipped to me was dry and blew air no problem. The other was the HE I removed my SRT and I guess I didn't drain it cause it shot coolant up the wall..
Perhaps your factory HE is clogged or damaged.
Perhaps your factory HE is clogged or damaged.
Thread Starter
|
Senior Member
Joined: Feb 2008
Posts: 4,508
Likes: 30
From: VA
Re: A better understanding of the I/C system
I added my Let H/E to my car some time ago and felt that the factory blue/green was partially contaminated when I first got into it. Second owner, was a factory dealer car previously.
At that time I flushed the coolant system and used a mild prestone radiator cleaner per the instructions. Some stuff came out and after I replaced the stock pump I opened it up to find a thin layer of crud inside the pump body that I photographed, in a posting earlier.
I will have to figure how to take a photo of the pipes on the stock H/E to show the small passages that I found to be restrictive. I had flushed the factory core many times with a hose after it was out to see if I had found something, BUT nothing showed and it is still restrictive when I use my mouth to blow it. I have measured the max force that I can blow ( yeah bring on the yucks now ) to be about 2 psi for a very short time on the gauge. The hose with a 50 psi well pump setting could get a flow but the H/E pumps generate less than that.
The CM30P7-1 johnson specs per page 18 are as follows
.................................................. .................................................. .............AMPS
Head in feet.......... liters/min........... Gallons / min ................12V
3.3 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,26,,,,,,,,,,,,,,,,, 6.9,,,,,,,,,,,,,,,,,,,,,,,,,,,, 2.2
6.6,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 19.5,,,,,,,,,,,,,,, 5.4,,,,,,,,,,,,,,,,,,,,,,,,,,,, 2.0
9.8,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 9.0,,,,,,,,,,,,,,,,2.4,,,,,,,,,,,,,,,,,,,,,,,,,,,, , 1.7
3.3 feet of height or head is about 1 meter or about 1.5 psi of back pressure and as you see the current draw goes down as restriction goes up. This is due to increased slippage or cavitation at the impellor of the pump. There is not much pressure to work with here and a large overall restriction will be troublesome.
Again, with all hooked up my LET flowed 3.7 GPM and my first test first pass with my own LARGE H/E was 1.5 GPM with two cores in series. I re-piped my H/E to have twin cores in parallel which netted my a flow of 3.1 GPM, all measured in the car using the stock electrical wiring and battery.
I would ask anyone that is draining the radiator to catch the antifreeze in a container after it is run thru a CLEAN cloth to see if there is any debris in their system. You never know.
Straining to get the facts, Woody Enjoy
At that time I flushed the coolant system and used a mild prestone radiator cleaner per the instructions. Some stuff came out and after I replaced the stock pump I opened it up to find a thin layer of crud inside the pump body that I photographed, in a posting earlier.
I will have to figure how to take a photo of the pipes on the stock H/E to show the small passages that I found to be restrictive. I had flushed the factory core many times with a hose after it was out to see if I had found something, BUT nothing showed and it is still restrictive when I use my mouth to blow it. I have measured the max force that I can blow ( yeah bring on the yucks now ) to be about 2 psi for a very short time on the gauge. The hose with a 50 psi well pump setting could get a flow but the H/E pumps generate less than that.
The CM30P7-1 johnson specs per page 18 are as follows
.................................................. .................................................. .............AMPS
Head in feet.......... liters/min........... Gallons / min ................12V
3.3 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,26,,,,,,,,,,,,,,,,, 6.9,,,,,,,,,,,,,,,,,,,,,,,,,,,, 2.2
6.6,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 19.5,,,,,,,,,,,,,,, 5.4,,,,,,,,,,,,,,,,,,,,,,,,,,,, 2.0
9.8,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 9.0,,,,,,,,,,,,,,,,2.4,,,,,,,,,,,,,,,,,,,,,,,,,,,, , 1.7
3.3 feet of height or head is about 1 meter or about 1.5 psi of back pressure and as you see the current draw goes down as restriction goes up. This is due to increased slippage or cavitation at the impellor of the pump. There is not much pressure to work with here and a large overall restriction will be troublesome.
Again, with all hooked up my LET flowed 3.7 GPM and my first test first pass with my own LARGE H/E was 1.5 GPM with two cores in series. I re-piped my H/E to have twin cores in parallel which netted my a flow of 3.1 GPM, all measured in the car using the stock electrical wiring and battery.
I would ask anyone that is draining the radiator to catch the antifreeze in a container after it is run thru a CLEAN cloth to see if there is any debris in their system. You never know.
Straining to get the facts, Woody Enjoy
Last edited by waldig; 09-03-2008 at 02:06 PM.
Re: A better understanding of the I/C system
I'm considering upgrading from the Johnson Marine Pump to this one from Meziere. It's only $60 more and flows 3X the coolant with an unconditional 2 year warranty.
http://www.meziere.com/ps-892-860-wp136s.aspx
http://www.meziere.com/ps-892-860-wp136s.aspx
Thread Starter
|
Senior Member
Joined: Feb 2008
Posts: 4,508
Likes: 30
From: VA
Re: A better understanding of the I/C system
Pump looks interesting and it does have a free flow rating up to 20GPM. THe 6-7 amp load should be ok, though the fuse should be increased from 10amps ( #13) to a bit more to be safe.
I wish I knew the flow curve to see what it is rated at as far as pressure capacity. Free flow is good but the increase of water flow would need an non-linear pressure to achieve it, like 6 to 9 times the current pumps rating.
More flow assists in cooling by promoting better "scrubbing " of the exchanger surfaces, both of them I/C and H/E.
Bubbling over with interest, Woody
I wish I knew the flow curve to see what it is rated at as far as pressure capacity. Free flow is good but the increase of water flow would need an non-linear pressure to achieve it, like 6 to 9 times the current pumps rating.
More flow assists in cooling by promoting better "scrubbing " of the exchanger surfaces, both of them I/C and H/E.
Bubbling over with interest, Woody
Joined: Dec 2007
Posts: 165
Likes: 0
Re: A better understanding of the I/C system
When I vented my IC-Circuit last week on my SLK32, I pinched the hose for the hot water which comes out of the IC quite HARD. I was VERY SURPRISED how fast and strong the Johnson CM30 is pumping the water through the hoses!! In a few seconds a big empty Cucumber-glass, dont know if this word exists 
,was full of IC-Fluid. Maybe when a stronger pump is pumping too fast, the water has no time to absorb the heat in the HE and IC ? In the MB-World forum it has been said for example that the Johnson CM90 (bigger than CM30) is not better for the 32AMG. Interesting...
,was full of IC-Fluid. Maybe when a stronger pump is pumping too fast, the water has no time to absorb the heat in the HE and IC ? In the MB-World forum it has been said for example that the Johnson CM90 (bigger than CM30) is not better for the 32AMG. Interesting...
Forum Regular
Joined: Oct 2007
Posts: 665
Likes: 1
Re: A better understanding of the I/C system
Too rapid a flow is not good either, you need the water to stay in the H/E long enough to have some type of cooling effect. I would think the LET H/E by itself with the factory pump would show some decent cooling. It has a larger surface area exposed to the air for cooling, this alone should be beneficial.
Thread Starter
|
Senior Member
Joined: Feb 2008
Posts: 4,508
Likes: 30
From: VA
Re: A better understanding of the I/C system
As the liquid is moved more quickley it scrubs the walls and breaks-up the laminar boundry flow at the surface. This promotes better heat thansfer and thus cooling. The faster the water moves up to a point, the more that you utilize the available area of the pair of heat exchangers.
Brian has listed a nice article that addressed this very topic with some depth.
You do not want to get into an extreme situation that would cause cavitation and generate bubbles. That can lead to erosion of impellers or tubing and poor transfer of heat. There is an upper limit to most things. Cost and size / weight not withstanding, the larger the heat exchangers, the more effective their transfer of heat energy will be.
Woody
Brian has listed a nice article that addressed this very topic with some depth.
You do not want to get into an extreme situation that would cause cavitation and generate bubbles. That can lead to erosion of impellers or tubing and poor transfer of heat. There is an upper limit to most things. Cost and size / weight not withstanding, the larger the heat exchangers, the more effective their transfer of heat energy will be.
Woody
Senior Member
Joined: Nov 2007
Posts: 1,225
Likes: 0
Re: A better understanding of the I/C system
Originally Posted by waldig
As the liquid is moved more quickley it scrubs the walls and breaks-up the laminar boundry flow at the surface. This promotes better heat thansfer and thus cooling. The faster the water moves up to a point, the more that you utilize the available area of the pair of heat exchangers.
Brian has listed a nice article that addressed this very topic with some depth.
You do not want to get into an extreme situation that would cause cavitation and generate bubbles. That can lead to erosion of impellers or tubing and poor transfer of heat. There is an upper limit to most things. Cost and size / weight not withstanding, the larger the heat exchangers, the more effective their transfer of heat energy will be.
Woody
Brian has listed a nice article that addressed this very topic with some depth.
You do not want to get into an extreme situation that would cause cavitation and generate bubbles. That can lead to erosion of impellers or tubing and poor transfer of heat. There is an upper limit to most things. Cost and size / weight not withstanding, the larger the heat exchangers, the more effective their transfer of heat energy will be.
Woody
Sorry this is off topic but you post a lot so i figured if im gonna read it here on good ole' company time my eyes need to be comfortable.
