Heat Exchanger with or without fans
- Thread starter Joe Muia
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I have a switch setup in the cabin for the fans on my VMP triple pass. I do not have a stock IC system.
J2 16 an inlet and outlet intercooler mod
1" lines all around.
EMP pump
Ice tank with 1" inlet and outlet on the tank and heat exchanger
Using 50/50 coolant/water
I turn off the fans and there to see if there is a noticeable difference in the IAT2 temps. I don't have IC water temp sensors setup.
With the fans on vs the fans off I usually see a difference of up to 5 degrees cruising around. BUT that could be the difference in the by-pass. If I turn on the fans after driving around without it being on it takes 30 mins to see it drop. BUT that is another 30 mins of driving around and could be the difference in the bypass being opened vs closed.
In either case as soon as I get into boost the IAT2 temp nose dives when the bypass closes. I am temped to take off the triple pass and modify a stock 13/14 exchanger to accept the 1" inlet and outlet and test to see if the flow improves with removing restriction.
I have been told by a couple people that flow is more important than the triple pass which makes me think I should try it.
J2 16 an inlet and outlet intercooler mod
1" lines all around.
EMP pump
Ice tank with 1" inlet and outlet on the tank and heat exchanger
Using 50/50 coolant/water
I turn off the fans and there to see if there is a noticeable difference in the IAT2 temps. I don't have IC water temp sensors setup.
With the fans on vs the fans off I usually see a difference of up to 5 degrees cruising around. BUT that could be the difference in the by-pass. If I turn on the fans after driving around without it being on it takes 30 mins to see it drop. BUT that is another 30 mins of driving around and could be the difference in the bypass being opened vs closed.
In either case as soon as I get into boost the IAT2 temp nose dives when the bypass closes. I am temped to take off the triple pass and modify a stock 13/14 exchanger to accept the 1" inlet and outlet and test to see if the flow improves with removing restriction.
I have been told by a couple people that flow is more important than the triple pass which makes me think I should try it.
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Whether the fans are on or off they are still impeding air flow to the heat exchanger, a better test is to remove them.
Agreed. I know the IAT2 data isn't a solid test but I am starting to think that the fans really don't do much and are more of a feel good with my setup. If I am going to the strip I am loading the tank with ice anyways and pulling the hotter ambient air through it in the staging lanes does not help. If I am doing runs on the highway I am getting enough airflow as is.
On a stock style system I have no idea though.
Thanks for the picture. That actually helps alot to see how others have done it.
If you aren’t in boost, the bypass is open and air isn’t going to be much hotter anyways. The climb in IAT2’s is due to low airflow, not actual fluid temp, hence the immediate and drastic drop once you get into boost.
Edited to correct closed to open
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When not in boost the bypass is open. Idle to mid throttle the bypass is open, mid to full throttle the bypass is closed.
Correct, sorry I wrote that backwards. It doesn’t have anything to do with throttle position, it’s vacuum vs boost, although depending on your vehicle that may be where the transition occurs. Operating principle remains the same
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