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Mountune Radiator questions

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Huntington Beach
#1
1. Will upgrading to the Mountune unit help keep my air conditioning cool as well? It seems every time I go to Vegas and it’s 110+ outside my car begins overheating at idle, and even when the temps are under “control” 235* on highway the Air Conditioning never feels cold.

2. I notice a pretty big power hit when it’s hot outside. Will having cooler coolant temps control result in noticeably more stable power?
 


OP
JorJorBinks
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Thread Starter #3
Not sure on the A/C. I think it’s a separate system altogether with the refrigeration cycle totally contained.

It will definitely help with heat soak, as will increasing the ratio of water to coolant.
I’m thinking for the A/C by adding extra cooling capacity it’ll take some heat out of the engine bay and free up capacity for the A/C.
And I didn’t know the power loss I felt is heat soak. 👍 so one answer found. I hope someone can chime in from a hotter region to touch on my 1st question. Thanks dhminer 🤙
 


Dpro

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#4
I’m thinking for the A/C by adding extra cooling capacity it’ll take some heat out of the engine bay and free up capacity for the A/C.
And I didn’t know the power loss I felt is heat soak. 👍 so one answer found. I hope someone can chime in from a hotter region to touch on my 1st question. Thanks dhminer 🤙
I am in SoCal and honestly running 235 temps is not ideal in my book . I run around 195-200 on a hot day and I do run a Mountune radiator and Intercooler. When your engine gets super hot it does affect charge air temps.
Running in 100 degree weather effects charge temps and you will be down on power getting a larger intercooler helps as it does not heat as quickly Plus our stock ones are too small.

think both intercooler and radiator are wise upgrades on our cars. As for freeing up capacity for your AC your AC condenser is in front of your radiator not behind it your intercooler is in front of both.
 


OP
JorJorBinks
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Thread Starter #5
I am in SoCal and honestly running 235 temps is not ideal in my book . I run around 195-200 on a hot day and I do run a Mountune radiator and Intercooler. When your engine gets super hot it does affect charge air temps.
Running in 100 degree weather effects charge temps and you will be down on power getting a larger intercooler helps as it does not heat as quickly Plus our stock ones are too small.

think both intercooler and radiator are wise upgrades on our cars. As for freeing up capacity for your AC your AC condenser is in front of your radiator not behind it your intercooler is in front of both.
Oops, probably should’ve mentioned I have a Cobb FMIC. But Dpro on a very hot day let’s say 100+ outside do you notice your A/C struggling to keep cool?
 


akiraproject24

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#6
Oops, probably should’ve mentioned I have a Cobb FMIC. But Dpro on a very hot day let’s say 100+ outside do you notice your A/C struggling to keep cool?
A ceramic based tint would probably help your a/c keep up with cabin temps. The radiator will keep your coolant/engine temps running lower which will make the car less likely to get into those extra high running temps when you put the a/c on.
 


OP
JorJorBinks
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Thread Starter #7
A ceramic based tint would probably help your a/c keep up with cabin temps. The radiator will keep your coolant/engine temps running lower which will make the car less likely to get into those extra high running temps when you put the a/c on.
Also should mention I have some decent Rayno S9 window tint on everything but my windshield. Specifically I’m just trying to isolate if my high coolant temps have anything to do with my power loss and if that extra bit of cooling would perhaps make the A/C run colder. Cause in my head I imagine if the radiator isn’t completely heat soaked it may be able to draw some heat from the A/C condenser? I just want to justify my radiator purchase by doing something more than extending my canyon run season here in SoCal. 🤙
 


XR650R

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#8
Also should mention I have some decent Rayno S9 window tint on everything but my windshield. Specifically I’m just trying to isolate if my high coolant temps have anything to do with my power loss and if that extra bit of cooling would perhaps make the A/C run colder. Cause in my head I imagine if the radiator isn’t completely heat soaked it may be able to draw some heat from the A/C condenser? I just want to justify my radiator purchase by doing something more than extending my canyon run season here in SoCal. 🤙
Yes. High temperatures mean less air density in the charge, so you'll lose power. Your radiator and intercooler will get heat soak.
A better radiator will cool it down, and with better heat management under the hood, your AC will cool better, too.
My car absolutely rips in cold weather. Cold air going through a cool intercooler really makes it peppy compared to a hot-day freeway burn.
 


OP
JorJorBinks
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Thread Starter #9
Yes. High temperatures mean less air density in the charge, so you'll lose power. Your radiator and intercooler will get heat soak.
A better radiator will cool it down, and with better heat management under the hood, your AC will cool better, too.
My car absolutely rips in cold weather. Cold air going through a cool intercooler really makes it peppy compared to a hot-day freeway burn.
Awesome! Okay it’s great to know that others also experience the power fluctuations. Love my winter power, and I hate the power loss in the heat. Thanks for the extra input! It’s much appreciated. 👍
 


akiraproject24

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#11
Awesome! Okay it’s great to know that others also experience the power fluctuations. Love my winter power, and I hate the power loss in the heat. Thanks for the extra input! It’s much appreciated. 👍
Check out the Koyo Radiator as well. They are a very well regarded radiator company.
 


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Pharr, TX, USA
#12
eBay radiator here and I live in deep south Texas(Mexican border) save some money and get a mishimoto clone off eBay. They work just the same as the name brands
 


OP
JorJorBinks
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Thread Starter #13
eBay radiator here and I live in deep south Texas(Mexican border) save some money and get a mishimoto clone off eBay. They work just the same as the name brands
I’m not too worried about the price, so much as having a problem down the line. Plus the time it’ll take me to install an Ebay clone that doesn’t properly fit will negate any benefits of $$$ savings. Not to mention if it fails I’ll fallback onto a Mountune anyway. Lol I appreciate the input though. ♥️
 


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#14
I’m not too worried about the price, so much as having a problem down the line. Plus the time it’ll take me to install an Ebay clone that doesn’t properly fit will negate any benefits of $$$ savings. Not to mention if it fails I’ll fallback onto a Mountune anyway. Lol I appreciate the input though. ♥️
Understand that, but I've installed three radiators in three different Fiesta STs. My own eBay mishimoto clone early version that needed fabrication work(going on three years old with about 60k miles), a mountune radiator, and the third was another eBay mishimoto clone (same brand as mine GPI racing) which was updated to be a complete drop in no fabrication needed.
 


OP
JorJorBinks
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Thread Starter #15
Understand that, but I've installed three radiators in three different Fiesta STs. My own eBay mishimoto clone early version that needed fabrication work(going on three years old with about 60k miles), a mountune radiator, and the third was another eBay mishimoto clone (same brand as mine GPI racing) which was updated to be a complete drop in no fabrication needed.
Alright you’ve convinced me. Lol! Are you able to link the one you have? I’m just going based off old info where we had to still do some modifying to get it to totally fit.
 


OP
JorJorBinks
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Thread Starter #18
OP
JorJorBinks
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Thread Starter #19
Alright got that new Rad mounted up, and now my radiator fan doesn’t kick on. The AC doesn’t blow cold while sitting still, and the car gets hot 220*. Once I’m moving it rapidly drops to 175*. So I don’t think it’s a bleeding issue, not sure what I can do besides reseat all the plugs and such.
Any input would be great!
 


OP
JorJorBinks
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Location
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Thread Starter #20
Alright got that new Rad mounted up, and now my radiator fan doesn’t kick on. The AC doesn’t blow cold while sitting still, and the car gets hot 220*. Once I’m moving it rapidly drops to 175*. So I don’t think it’s a bleeding issue, not sure what I can do besides reseat all the plugs and such.
Any input would be great!
Aaaaaand reseating the plugs did the trick. The car now holds steady at 190*F idling, turning on the AC dips the coolant temps a little lower. Can’t wait to see how it does on a hot Vegas day. 🤙

Also if anyone is reading this and is deciding to go with the eBay clones, make sure you get the fan shroud made for the radiator you’re buying, or be very handy and make one yourself. The stock fan shroud did not fit the clone Raziel510 listed.
 


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