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Thermostat question.

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Las Vegas
#1
I'm upgrading to a Mishimoto radiator at the end of the month and I'm debating whether to swap the thermostat out at the same time. I really think the 160 degree thermostat that mishimoto offers is a little too low in temp so I was looking for other options.

I called the dealer and asked for the part number and was given #RT1211 which is the motorcraft replacement. The dealer said the activation temp on it is 82 degrees Celsius which is179 degrees. I went to O'Reilly auto parts and they offered only one thermostat for our cars and it was coincidentally the same motorcraft part number but in the description has it listed at a 190 degree activation temp.

So I look back at the mishimoto page and it lists the benefits of it's thermostat at a 160 degree temp vs the OEM activation temp of 209 degrees. I'm like, wtf. Who has the right info of the activation temp of our damn thermostats. If the factory one is indeed 180-190 degrees I would prefer keeping the stock one in place but if it is indeed a 209 degree activation temp I'd consider swapping it for the stock replacement (which really makes no sense in theory why they would have changed the activation temp for stock replacements) or even the mishimoto160 degree one.

Idk... Seems like a lot of misinformation or something. Any guys swap the radiator without the mishimoto thermostat? Anyone know the real activation temp of our stock thermostats and if it's not 209 degrees like mishimoto says it is, how the f*ck did they come up with that number?
 


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Crystal, MN, USA
#2
Idk... Seems like a lot of misinformation or something. Any guys swap the radiator without the mishimoto thermostat? Anyone know the real activation temp of our stock thermostats and if it's not 209 degrees like mishimoto says it is, how the f*ck did they come up with that number?
I didn't touch the thermostat on mine, when I swapped in the Mishi radiator...my AP reads coolant temps reach 193.7ish usually before the temps drop from the cycle of coolant, depends on how hard you're driving. Cruising, my coolant temps range from 184-189. Pretty steady...
 


OP
AntTrain
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Thread Starter #3
I didn't touch the thermostat on mine, when I swapped in the Mishi radiator...my AP reads coolant temps reach 193.7ish usually before the temps drop from the cycle of coolant, depends on how hard you're driving. Cruising, my coolant temps range from 184-189. Pretty steady...
Where do you live? Just curious (climate)
 


Woods247

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#4
I didn't touch the thermostat on mine, when I swapped in the Mishi radiator...my AP reads coolant temps reach 193.7ish usually before the temps drop from the cycle of coolant, depends on how hard you're driving. Cruising, my coolant temps range from 184-189. Pretty steady...
I did the same thing and have the same numbers. I'm in Atlanta where outside temps are in the high 70s low 80s. I'll track it Wednesday at Road ATL and see what the temps are. It's supposed to be pretty hot here Wednesday.
I thought about swapping the thermostat too, but it looked like a total bitch to change. If I still have heat issues I'll install an oil cooler and swap out the antifreeze for MoCool and distilled water until Fall.
 


OP
AntTrain
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Thread Starter #5
Reason I'm asking is I'm located here in Las Vegas, NV. It's 100+ a few months of the year
 


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Location
Edmonton
#6
Ford is correct at 179 degrees.

The thermostat opens at 179 degrees which means that average driving temps, as mentioned above are around 190 degrees. Most vehicles driving temp is on average around 10-15 degrees higher then the thermostat opening temp.

Mishomoto is out to lunch on their numbers as 209 doesn't make sense. My car never exceeds around the 200 degree mark.

The parts store just carries a generic aftermarket replacement and its at a rating that would suit a variety of models.
 


OP
AntTrain
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Thread Starter #7
Do you guys think the mishimoto thermostat has any value for a street/track car specially in my hot climate. Doesn't seem like it would have any benefits even when racing as long as the upgraded radiator can sustain 190 degrees even when racing. Btw I plan on doing the oil cooler at the same time.

I wonder why mishimoto had to put out the bogus 209 degree number. Seems odd.
 


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286
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Location
Crystal, MN, USA
#9
I did the same thing and have the same numbers. I'm in Atlanta where outside temps are in the high 70s low 80s. I'll track it Wednesday at Road ATL and see what the temps are. It's supposed to be pretty hot here Wednesday.
I thought about swapping the thermostat too, but it looked like a total bitch to change. If I still have heat issues I'll install an oil cooler and swap out the antifreeze for MoCool and distilled water until Fall.
Thought crossed my mind, but I passed on it. Total bitch is an understatement lol. I'm running the orange antifreeze from Ford. I actually got it cheaper at the dealership vs. amazon
 


M-Sport fan

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#10
Do you guys think the mishimoto thermostat has any value for a street/track car specially in my hot climate. Doesn't seem like it would have any benefits even when racing as long as the upgraded radiator can sustain 190 degrees even when racing. Btw I plan on doing the oil cooler at the same time.
Is this going to be a year 'round daily driver, and if so, how cold does it get there in the winter?

Did you opt for the thermostatic oil cooler adapter fitting from Mishi or not?


I wonder why mishimoto had to put out the bogus 209 degree number. Seems odd.
Maybe to scare the bejeebus out of everyone, and make them run to buy their t-stat?? [dunno]
 


grnmachine02

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Fredericksburg
#11
Ford is correct at 179 degrees.

The thermostat opens at 179 degrees which means that average driving temps, as mentioned above are around 190 degrees. Most vehicles driving temp is on average around 10-15 degrees higher then the thermostat opening temp.

Mishomoto is out to lunch on their numbers as 209 doesn't make sense. My car never exceeds around the 200 degree mark.

The parts store just carries a generic aftermarket replacement and its at a rating that would suit a variety of models.
I saw 215 degree temps sitting in traffic yesterday. A decent uphill mountain road with "spirited driving" will generally give me temps of 210ish. I may pull the trigger on a radiator soon. Much like OP, I have no desire to go balls deep in this car to replace the thermostat.
 


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Location
Arlington, VA
#12
I saw 215 degree temps sitting in traffic yesterday. A decent uphill mountain road with "spirited driving" will generally give me temps of 210ish. I may pull the trigger on a radiator soon. Much like OP, I have no desire to go balls deep in this car to replace the thermostat.
That's kinda nuts unless that road was reeeeallly hot. It wasn't even that warm yesterday. What year is your car? You have enough coolant in it?

In any case, I don't see how a thermostat is really going to affect things much during most conditions. If it's hot or you are pushing the car, the thermostat is going to be open anyway. If you are tracking and having overheating issues, you might see a slightly longer time before it over heats, but the amount of time it will take for the coolant to go from 170ish (mishi tstat) to 190ish (stock tstat) is probably minimal under that scenario. After that, it's all down to the size of the radiator, the efficiency of the coolant, ambient temp, and how hard you are pushing the car. Those will be the same regardless of the thermostat as I understand it.
 


grnmachine02

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#13
2015, the "updated" head, plenty of coolant. Last time I was at the dragon I saw numerous fiestas pulled over because they had over heated. Hell, the dummy gauge on the dash doesn't even show over heated until you're into the 230 degree range. Thankfully, my car has never over heated. The cooling system on these cars is just barely adequate. The day I brought it home from the dealer I saw 220 degrees sitting in bumper to bumper traffic.
 


CarGuy

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#14
2015, the "updated" head, plenty of coolant. Last time I was at the dragon I saw numerous fiestas pulled over because they had over heated. Hell, the dummy gauge on the dash doesn't even show over heated until you're into the 230 degree range. Thankfully, my car has never over heated. The cooling system on these cars is just barely adequate. The day I brought it home from the dealer I saw 220 degrees sitting in bumper to bumper traffic.
The "updated head"??? Catch me up, what is that?


Sent from my SM-N920V using Tapatalk
 


Hijinx

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Auburn, AL, USA
#15
I have the Mishimoto 160* T-stat in the stock radiator. My temp usually sits around 182-185* at cruise in warm weather. 175ish down in the 20s. I don't take the car out if it's lower than that... Caveat here is that I change my oil relatively frequent (3k or less, racecar life). Anyway, even with 1/2 mile WOT racing, I doesn't go much over 200* and gets back down to the 180s within a few minutes.
 


grnmachine02

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#16
The "updated head"??? Catch me up, what is that?


Sent from my SM-N920V using Tapatalk
At some point Ford added a sensor to the back of the head to deal with the head cracking issues on the Escape. Since this is the same engine in the Fiesta, some cars have that, there's a date cutoff that I can't remember.

At least that's my understanding of it. Ford has been quietly dealing with the head cracking/ death by fire issue for a number of years now .
 


CarGuy

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#17
At some point Ford added a sensor to the back of the head to deal with the head cracking issues on the Escape. Since this is the same engine in the Fiesta, some cars have that, there's a date cutoff that I can't remember.

At least that's my understanding of it. Ford has been quietly dealing with the head cracking/ death by fire issue for a number of years now .
I had no idea about this. I do have a 2015 FiST but an early one as I purchased it in November of 2014. Good to know. I'm glad I asked.

Sent from my SM-N920V using Tapatalk
 


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Arlington, VA
#18

jmrtsus

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#19
2015, the "updated" head, plenty of coolant. Last time I was at the dragon I saw numerous fiestas pulled over because they had over heated. Hell, the dummy gauge on the dash doesn't even show over heated until you're into the 230 degree range. Thankfully, my car has never over heated. The cooling system on these cars is just barely adequate. The day I brought it home from the dealer I saw 220 degrees sitting in bumper to bumper traffic.
Ran the TOTD two times last summer, NC to TN both times with my 2016 W/Mountune 215 and stock cooling, A/C on, temp gauge went to 4 bars toward the end once but still in the normal range. Spent many hours in bumper to bumper traffic in Atlanta last summer with anger issues but not cooling issues.

Wonder what changes were made to the '16? Are you running a front plate? I'm not but it seems to me the way it was placed would affect air flow. Also did 3 trips to New Orleans in July/August with no issues. Hope it stays that way.
 


grnmachine02

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#20
Ran the TOTD two times last summer, NC to TN both times with my 2016 W/Mountune 215 and stock cooling, A/C on, temp gauge went to 4 bars toward the end once but still in the normal range. Spent many hours in bumper to bumper traffic in Atlanta last summer with anger issues but not cooling issues.

Wonder what changes were made to the '16? Are you running a front plate? I'm not but it seems to me the way it was placed would affect air flow. Also did 3 trips to New Orleans in July/August with no issues. Hope it stays that way.
Thankfully my car has never actually overheated. Seems bumper to bumper traffic in the summer is what it doesn't like. I see higher temps there than I do running the dragon. Weird.

Anyhow, I am running a front plate (thanks Virginia!) I think I'm gonna get the DHM crashbar and shave the grill. Might even do the mishimoto radiator then as well, seeing as I'm already halfway there doing the crash bar.
 




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