A2W (no ice) vs A2A ?
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A2W (no ice) vs A2A ? So I have 2014 chevy SS
F1A procharger
Built LS3
"Max effort" street roll racing car
space is only enough for 4.0" thick A2A intercooler, so what is the better option for me ? 4" A2A or A2W (no ice except on kill mode)
Any recommendations for A2W setup ?
F1A procharger
Built LS3
"Max effort" street roll racing car
space is only enough for 4.0" thick A2A intercooler, so what is the better option for me ? 4" A2A or A2W (no ice except on kill mode)
Any recommendations for A2W setup ?
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Joined: Jan 2002
Posts: 299
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From: Detroit, Murder City
A 4" thick A2A core should be very effective as long as the car is moving. A2A isn't great at the drag strip where you build up heat in the staging lanes and burnout box right before you need a cooler, but they generally work well on the street. The trick is usually packaging them and getting the air in/out.
A2W works really well for short bursts (drag strip, single roll event at a time) where you have time to let the water cool back down in between runs. Water is really good at absorbing heat, not so great at rejecting it, so you need either a huge low temp radiator or more reservoir capacity as the length of time you want effective cooling increases. This makes them lousy for things like road racing lap after lap without gigantic low temp radiators and more coolant capacity (at 8# per gallon!). The benefit is that it's sometimes easier to package the smaller A2W intercooler core in the engine bay and you can do things like an ice bath or killer chiller (A/C cooler) to bring the water temp well below ambient for better cooling. All it takes is money.
A2W works really well for short bursts (drag strip, single roll event at a time) where you have time to let the water cool back down in between runs. Water is really good at absorbing heat, not so great at rejecting it, so you need either a huge low temp radiator or more reservoir capacity as the length of time you want effective cooling increases. This makes them lousy for things like road racing lap after lap without gigantic low temp radiators and more coolant capacity (at 8# per gallon!). The benefit is that it's sometimes easier to package the smaller A2W intercooler core in the engine bay and you can do things like an ice bath or killer chiller (A/C cooler) to bring the water temp well below ambient for better cooling. All it takes is money.
Depends on the setup/fuel and how you use the car. In my experience a heat exchanger wasn't needed at all. *IF* your only doing a couple quick pulls and you use a big tank. Only circulate the water while in boost. Your tank will have ambient temperature water in it. My experience was with a 10 gallon igloo cooler in the trunk about 3/4 full and a rule 2000 pump setup on a 5psi switch. Also a nice plus to have it all mountable in the rear of the car/truck. Also depending on fuel used you may not need great charge temps. What are the power goals? Defiantly benefits to not having a 30lb IC on the nose of the car blocking all your radiator airflow.
Depends on the setup/fuel and how you use the car. In my experience a heat exchanger wasn't needed at all. *IF* your only doing a couple quick pulls and you use a big tank. Only circulate the water while in boost. Your tank will have ambient temperature water in it. My experience was with a 10 gallon igloo cooler in the trunk about 3/4 full and a rule 2000 pump setup on a 5psi switch. Also a nice plus to have it all mountable in the rear of the car/truck. Also depending on fuel used you may not need great charge temps. What are the power goals? Defiantly benefits to not having a 30lb IC on the nose of the car blocking all your radiator airflow.
If its truly a max effort car then I would run more core then you actually need, probably close to a 2000hp "rated core" as that blower will probably only eek out 1100hp and you won't have to worry about IAT's at all. Plus its nice not having to worry about ice, heat exchangers, etc...
Which A2W cooler do you run? The length of piping from back to front acts like a bit of a heat sink I'd bet. The remote mount guys tend to have lower IAT's as well. Put it all in the bed! 
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No heat exchanger or ice needed as long as the core is up to the task. I haven't run a heat exchanger or ice on any of my A2W setups and they work great, I barely even turn the pump on. But I also have more core then I need, compared to a 30x12.5x4.5 A2A unit my IAT's are a good 30+* lower through two 10x9x4.5 A2W cores even with no heat exchanger, no ice and with pump off.
Even on long drives with multiple pulls along the way my IAT's don't get hot at all without turning on the pump. I tested my A2W cores without any water at all first to see how they performed, and even then they did pretty good. It comes down to sizing the core properly, I use a much larger core then I need but it still takes up less space then my A2A did and like you said most of the weight is in a better spot. My IAT's barely rise during a 1/4 mile pull with the pump off, but with back to back repeated pulls I cycle the pump to get fresh water into the core. I use a 5 gal tank 1" lines and rule 2000 as well. Good point about fuel, on E85 it doesn't seem to care much if your IAT's are 85 or 150, I've run 220+ IAT's on E and it didn't care. Also agree on not blocking the rad, my coolant temp is lower now that I don't have an A2A core blocking it.
If its truly a max effort car then I would run more core then you actually need, probably close to a 2000hp "rated core" as that blower will probably only eek out 1100hp and you won't have to worry about IAT's at all. Plus its nice not having to worry about ice, heat exchangers, etc...
Even on long drives with multiple pulls along the way my IAT's don't get hot at all without turning on the pump. I tested my A2W cores without any water at all first to see how they performed, and even then they did pretty good. It comes down to sizing the core properly, I use a much larger core then I need but it still takes up less space then my A2A did and like you said most of the weight is in a better spot. My IAT's barely rise during a 1/4 mile pull with the pump off, but with back to back repeated pulls I cycle the pump to get fresh water into the core. I use a 5 gal tank 1" lines and rule 2000 as well. Good point about fuel, on E85 it doesn't seem to care much if your IAT's are 85 or 150, I've run 220+ IAT's on E and it didn't care. Also agree on not blocking the rad, my coolant temp is lower now that I don't have an A2A core blocking it.
If its truly a max effort car then I would run more core then you actually need, probably close to a 2000hp "rated core" as that blower will probably only eek out 1100hp and you won't have to worry about IAT's at all. Plus its nice not having to worry about ice, heat exchangers, etc...
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No heat exchanger or ice needed as long as the core is up to the task. I haven't run a heat exchanger or ice on any of my A2W setups and they work great, I barely even turn the pump on. But I also have more core then I need, compared to a 30x12.5x4.5 A2A unit my IAT's are a good 30+* lower through two 10x9x4.5 A2W cores even with no heat exchanger, no ice and with pump off.
Even on long drives with multiple pulls along the way my IAT's don't get hot at all without turning on the pump. I tested my A2W cores without any water at all first to see how they performed, and even then they did pretty good. It comes down to sizing the core properly, I use a much larger core then I need but it still takes up less space then my A2A did and like you said most of the weight is in a better spot. My IAT's barely rise during a 1/4 mile pull with the pump off, but with back to back repeated pulls I cycle the pump to get fresh water into the core. I use a 5 gal tank 1" lines and rule 2000 as well. Good point about fuel, on E85 it doesn't seem to care much if your IAT's are 85 or 150, I've run 220+ IAT's on E and it didn't care. Also agree on not blocking the rad, my coolant temp is lower now that I don't have an A2A core blocking it.
If its truly a max effort car then I would run more core then you actually need, probably close to a 2000hp "rated core" as that blower will probably only eek out 1100hp and you won't have to worry about IAT's at all. Plus its nice not having to worry about ice, heat exchangers, etc...
Even on long drives with multiple pulls along the way my IAT's don't get hot at all without turning on the pump. I tested my A2W cores without any water at all first to see how they performed, and even then they did pretty good. It comes down to sizing the core properly, I use a much larger core then I need but it still takes up less space then my A2A did and like you said most of the weight is in a better spot. My IAT's barely rise during a 1/4 mile pull with the pump off, but with back to back repeated pulls I cycle the pump to get fresh water into the core. I use a 5 gal tank 1" lines and rule 2000 as well. Good point about fuel, on E85 it doesn't seem to care much if your IAT's are 85 or 150, I've run 220+ IAT's on E and it didn't care. Also agree on not blocking the rad, my coolant temp is lower now that I don't have an A2A core blocking it.
If its truly a max effort car then I would run more core then you actually need, probably close to a 2000hp "rated core" as that blower will probably only eek out 1100hp and you won't have to worry about IAT's at all. Plus its nice not having to worry about ice, heat exchangers, etc...
Last edited by mtt14; May 16, 2020 at 04:34 PM.
Launching!
Joined: Jan 2002
Posts: 299
Likes: 41
From: Detroit, Murder City
Not true. Even though the bypass may be open, there is still plenty of heat being transferred to the incoming aircharge even under vacuum. I can't see wanting to drive anything on the street without a heat exchanger for the intercooler. You might as well eliminate the intercooler altogether at that point, since it will eventually heat soak to the same temps. The only difference is how long it takes to get there.
Not following that theory. There is zero need to cool the charge if no "boost" is present. There is a "heat sink" effect happening with the aluminum core and piping alone as well. It is clearly seen monitoring IAT's with the pump not running on an A2W setup. VS no core and a short length of piping installed. I've seen both. Also there are VERY clear benefits to circulating ambient water with a largish water tank while in boost only w/ no heat exchanger... also seen this in person. I don't tend to do extended pulls or more than a few back to back pulls personally. So I can't see the need for the added weight/expense/plumbing. Of a heat exchanger for typical 3-5 sec pulls.
Ok wow
Let's make this simple..
When the pump is running the water is trying to equalize temperature with whatever temp is entering the intercooler..... Fact.... Not a hard concept to grasp
Now here is the big difference between systems... What is the temperature of the air entering the cooler at cruise??
if you are drawing warm/hot off the engine bay into the turbo.... Then no you will never have water equalize any lower temp than that with the pump running
get a couple hits and that is that is it unless you discharge the heat in the water with a HE
.
.
.
If you are drawing ambient air into the turbo it is a different story
At cruise you are discharging water heat into the charge air... In other words it is acting as the HE in the system. While slower than a dedicated HE it is doing the same thing
This is a fact. I have as much data as anyone could ever take in. My pre cooler inlets while cruising run 10-15* above ambient max.... This is the temp the water is working to equalize to when the pump is running at cruise
Doesn't matter if you have a HE or not.... The best a2w system will have a recovery time .... And it will never be even as close to in line with a good a2a out on the highway.
All have pros and cons, like everything in life
Let's make this simple..
When the pump is running the water is trying to equalize temperature with whatever temp is entering the intercooler..... Fact.... Not a hard concept to grasp
Now here is the big difference between systems... What is the temperature of the air entering the cooler at cruise??
if you are drawing warm/hot off the engine bay into the turbo.... Then no you will never have water equalize any lower temp than that with the pump running
get a couple hits and that is that is it unless you discharge the heat in the water with a HE
.
.
.
If you are drawing ambient air into the turbo it is a different story
At cruise you are discharging water heat into the charge air... In other words it is acting as the HE in the system. While slower than a dedicated HE it is doing the same thing
This is a fact. I have as much data as anyone could ever take in. My pre cooler inlets while cruising run 10-15* above ambient max.... This is the temp the water is working to equalize to when the pump is running at cruise
Doesn't matter if you have a HE or not.... The best a2w system will have a recovery time .... And it will never be even as close to in line with a good a2a out on the highway.
All have pros and cons, like everything in life
im so on the fence I really want to run a fronzen boost type 12 a2w Intercooler, but have been so worried about making random pulls on the street without ice and iats rising after back to back pulls. I really enjoy taking my cars out and beating on them but seeing this makes me feel like I can beat on it with an a2w and not have to worry about iat’s getting too hot. I see John at Ljms saying you don’t have to run a heat exchanger because out of boost there is not heat. I figure with a 7 gallon tank and a 2000 hp Intercooler it would be fine on my 5.3/s475 or s480 combo.
Not true. Even though the bypass may be open, there is still plenty of heat being transferred to the incoming aircharge even under vacuum. I can't see wanting to drive anything on the street without a heat exchanger for the intercooler. You might as well eliminate the intercooler altogether at that point, since it will eventually heat soak to the same temps. The only difference is how long it takes to get there.
Not following that theory. There is zero need to cool the charge if no "boost" is present. There is a "heat sink" effect happening with the aluminum core and piping alone as well. It is clearly seen monitoring IAT's with the pump not running on an A2W setup. VS no core and a short length of piping installed. I've seen both. Also there are VERY clear benefits to circulating ambient water with a largish water tank while in boost only w/ no heat exchanger... also seen this in person. I don't tend to do extended pulls or more than a few back to back pulls personally. So I can't see the need for the added weight/expense/plumbing. Of a heat exchanger for typical 3-5 sec pulls.