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Coolant temps

Messages
130
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54
Location
Delaware, OH, USA
#1
I searched and didnt really see what I was looking for. I am just curious as to what temps these cars normally run at. I got mine late last year so I have really had the heat to see what it runs at. I know in the winter time It never went above 185, but since the last couple days its 91 or so in my area I have seen higher temps highest yet was 220 but dropped quickly.. I know these cars run hotter and I pretty much know the stock rad really isnt sufficient enough, just havent pulled the trigger on a an upgrade. Prolly going to order the 180 thermostat soon as well.
 


Messages
227
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398
Location
Poway, CA
#2
Before I got my Mountune radiator I would see 200+ consistently in Summer just driving in traffic. 212-220 was pretty much the norm. Never really got above that thankfully but this was also just normal driving. Nothing aggressive at all.
So your right in that range. As long as it doesn't get much hotter than that you're ok.

With my Mountune radiator I've yet to see 200 degrees. I've come very close and I'm sure I'll get there as it gets warmer, but no where near as hot as it was with the stock radiator.

I haven't messed with the thermostat as I've heard its a bitch to replace
 


TyphoonFiST

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Rich-fizzield
#3
Ill say 195-210 Depending on the day and season under normal driving conditions. Some cars got a different Thermostat also I've gathered.
 


Last edited:
Messages
287
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302
Location
Twin Falls, ID, USA
#4
@Dcs_grey_shoe09 FiSTs do run warm. Heat dissipation is almost an obsession of mine at this point. I had my FiST overheat in gridlock once and once during a spirited Touge run. I would also second what @James1980 said. After the Mountune Radiator I rarely see 200 though I do see it. The Mountune Radiator was such an easy install with so many benefits you'll only hear me praise and recommend that thing. If I could do it all over again my priority list would be 1) APV3 and Tune, 2) Mountune Radiator, 3) RMM, 4) Intake, 5) Motor Mounts - or inserts.
 


OP
Dcs_grey_shoe09
Messages
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Location
Delaware, OH, USA
Thread Starter #5
Thanks everyone, I was very curious to know what they ran at before it got up that way again. I was sitting there thinking when I saw it spike was like oh sh*t it's about to pop. I had remembered these things run hot but wasn't sure of the range these ran. I searched but didnt really turn up the normal range.

I will say I am going to be looking at getting a rad and while I'm at it prolly throw the 180 t-stat in there. Keeping temps down is definitely important to me and in anyway I can it will happen.
 


Messages
287
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302
Location
Twin Falls, ID, USA
#7
Thanks everyone, I was very curious to know what they ran at before it got up that way again. I was sitting there thinking when I saw it spike was like oh sh*t it's about to pop. I had remembered these things run hot but wasn't sure of the range these ran. I searched but didn't really turn up the normal range.
I will say I am going to be looking at getting rad and while I'm at it prolly throw the 180 t-stat in there. Keeping temps down is definitely important to me and in any way I can it will happen.
Being a data nerd, I can give you my observed testing. I commute daily ~120 miles. Of this, 50% is at sustained 70mph speeds and the remaining is stop and go. The average speed is approximately 35mph. Below 80f I have never noticed high temperatures. >80f I see temperatures that I do not like (doesn't mean it's bad per see). During my Touge overheat, I saw coolant at 247f, and oil was at 240f.

Pre-Radiator Upgrade: I was seeing oil temps ~235f and coolant about 225-230f at a sustained 70mph range. In stop and go traffic my oil temps would drop down to 190s, and coolant would go into the 210-220f range.
Post-Radiator Upgrade: Oil goes to about 210f and coolant about 195-198f at a sustained 70mph range. In stop and go traffic my oil temps have dropped down to 180s, I have even seen 160s, and coolant hangs out right around 195-198f. We haven't seen too many very hot days since the upgrade but I can update as information comes in.
 


SST

Member
Messages
185
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40
Location
Toronto
#8
@Dcs_grey_shoe09 FiSTs do run warm. Heat dissipation is almost an obsession of mine at this point. I had my FiST overheat in gridlock once and once during a spirited Touge run. I would also second what @James1980 said. After the Mountune Radiator I rarely see 200 though I do see it. The Mountune Radiator was such an easy install with so many benefits you'll only hear me praise and recommend that thing. If I could do it all over again my priority list would be 1) APV3 and Tune, 2) Mountune Radiator, 3) RMM, 4) Intake, 5) Motor Mounts - or inserts.

can i ask how easy was it? i assume removing bumper and the crash bar?
 


Messages
287
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302
Location
Twin Falls, ID, USA
#9
can i ask how easy was it? i assume removing bumper and the crash bar?
Easy enough I was concerned I must have skipped a step or done something wrong. By myself, I think it was about 2 hours. I didn't pull the bumper or crash bar (that's using the mishimoto instructions, mountune you go through the bottom).

My whole thread on determining radiator, install, and the normal keyboard warrior stuff near the end.
https://www.fiestastforum.com/threads/mountune-radiator-vs-mishimoto-radiator.23196/
 


SrsBsns

Active member
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695
Location
San Diego
#11
Pretty much echo what's been said.

I have a '15 and before the Mountune rad, I regularly saw temps near 220 in stop and go traffic. I overheated twice on mountain roads with the stock radiator.

The install for the Mountune is really pretty easy. I did a write up on mine if you search and there is a good video on Youtube that walks you through it.

If I were starting over with the car, I'd do the rad first and then start performance modding.

Here's a link to my post with the write up: https://www.fiestastforum.com/threads/thoughts-from-mountune-radiator-install.23121/#post-408853

There's a video at the end that is a good resource (not mine) and you should watch it once or twice before installing the radiator.
 


Last edited:
OP
Dcs_grey_shoe09
Messages
130
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54
Location
Delaware, OH, USA
Thread Starter #13
Being a data nerd, I can give you my observed testing. I commute daily ~120 miles. Of this, 50% is at sustained 70mph speeds and the remaining is stop and go. The average speed is approximately 35mph. Below 80f I have never noticed high temperatures. >80f I see temperatures that I do not like (doesn't mean it's bad per see). During my Touge overheat, I saw coolant at 247f, and oil was at 240f.

Pre-Radiator Upgrade: I was seeing oil temps ~235f and coolant about 225-230f at a sustained 70mph range. In stop and go traffic my oil temps would drop down to 190s, and coolant would go into the 210-220f range.
Post-Radiator Upgrade: Oil goes to about 210f and coolant about 195-198f at a sustained 70mph range. In stop and go traffic my oil temps have dropped down to 180s, I have even seen 160s, and coolant hangs out right around 195-198f. We haven't seen too many very hot days since the upgrade but I can update as information comes in.
Would like to get the oil cooler and the rad but definitely cant afford both right now. That is most definitely on my list, just wish I would've done that before I ordered my wheels🤦‍♂️. That is some great information and will use it to my advantage thanks for it all.
 


Messages
287
Likes
302
Location
Twin Falls, ID, USA
#14
Would like to get the oil cooler and the rad but definitely cant afford both right now. That is most definitely on my list, just wish I would've done that before I ordered my wheels🤦‍♂️. That is some great information and will use it to my advantage thanks for it all.
Glad to hear it! Nothing wrong with wheels. Rule #1 is to look cool.

1590707238749.png
 




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