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Fox what thermostat to run in the summer

  • Thread starter Thread starter mattys91gt
  • Start date Start date May 19, 2022
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    radiator thermostat
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mattys91gt

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May 19, 2022
#1
  • May 19, 2022
  • #1
what thermostat I should run for the summer since my heater core is bypassed will that effect the heat from the motor? and I put a stock thermostat in the other day, I had a 180 in there
 

96pushrod

I think they're a little easier to get off
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#2
  • May 19, 2022
  • #2
What car? Engine details?
 

mattys91gt

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#3
  • May 19, 2022
  • #3
96pushrod said:
What car? Engine details?
Click to expand...
sorry 91 mustang gt 5.0 automatic transmission aod and mostly stock motor
 

96pushrod

I think they're a little easier to get off
5 Year Member
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May 19, 2022
#4
  • May 19, 2022
  • #4
Heater core can shed a small amount of heat if the fan is on high, but it’s sorta negligible in the grand scheme of things.

Stock engine, stock thermostat is fine.
 

mattys91gt

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#5
  • May 19, 2022
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96pushrod said:
Heater core can shed a small amount of heat if the fan is on high, but it’s sorta negligible in the grand scheme of things.

Stock engine, stock thermostat is fine.
Click to expand...
heater core is bypassed tho
 

96pushrod

I think they're a little easier to get off
5 Year Member
May 15, 2018
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#6
  • May 19, 2022
  • #6
mattys91gt said:
heater core is bypassed tho
Click to expand...
I see, but that makes almost zero difference whatsoever. Compared to your radiator and fan the heater core and blower motor are tiny.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
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#7
  • May 20, 2022
  • #7
Stock 195


Running too cool can be detrimental to long-term health of the engine.
 
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mattys91gt

Active Member
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#8
  • May 20, 2022
  • #8
96pushrod said:
I see, but that makes almost zero difference whatsoever. Compared to your radiator and fan the heater core and blower motor are
Click to expand...

Mustang5L5 said:
Stock 195


Running too cool can be detrimental to long-term health of the engine.
Click to expand...
I had a 180 in there before I live in Massachusetts car is coverd in the winter time
 

vristang

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#9
  • May 20, 2022
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None of it matters… stock t-stat is what the ecu is programmed for.
 
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mikestang63

SN Certified Technician
Aug 27, 2012
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May 20, 2022
#10
  • May 20, 2022
  • #10
stock thermostat. I use the Mr Gasket or Stant. make sure you boil it to test it works before install.
 
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mattys91gt

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#11
  • May 20, 2022
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vristang said:
None of it matters… stock t-stat is what the ecu is programmed for.
Click to expand...
ok good I'm not sure what it is tho when I open the hood it's like opening a oven
 

7991LXnSHO

wanna catch the space herp
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#12
  • May 20, 2022
  • #12
mattys91gt said:
ok good I'm not sure what it is tho when I open the hood it's like opening a oven
Click to expand...
That’s why the passenger compartment is separated from the engine compartment by an insulated firewall.
What is your temp gauge reading? If in doubt, get a mechanical gauge to double check actual temp.
If you run a 160 deg thermostat, the engine will likely not get hot enough to boil the blowby out of the oil. And water with some gas is not what you want building up in the oil. The computer is likely to stay in warm up mode (open loop), possibly running quite rich, and not running best for ambient conditions.
And sure, a heater core works better with a higher temp thermostat, but that’s irrelevant in your case. The fuel injection system will not be happy with a low temp thermostat.
 

Mustang5L5

That is…until I whipped out my Bissell
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May 20, 2022
#13
  • May 20, 2022
  • #13
mattys91gt said:
ok good I'm not sure what it is tho when I open the hood it's like opening a oven
Click to expand...

I mean that’s typically what happens. Modern fuel injected engine is designed to run around 200-210 degrees. That’s enough to (almost) boil water.

These engines run efficient at that temp range. I don’t mean fuel economy, but in terms of driving off moisture and contaminants from the oil, proper engine clearances and other factors that contribute to a long-living engine.
 
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mattys91gt

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Feb 3, 2022
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#14
  • May 20, 2022
  • #14
7991LXnSHO said:
That’s why the passenger compartment is separated from the engine compartment by an insulated firewall.
What is your temp gauge reading? If in doubt, get a mechanical gauge to double check actual temp.
If you run a 160 deg thermostat, the engine will likely not get hot enough to boil the blowby out of the oil. And water with some gas is not what you want building up in the oil. The computer is likely to stay in warm up mode (open loop), possibly running quite rich, and not running best for ambient conditions.
And sure, a heater core works better with a higher temp thermostat, but that’s irrelevant in your case. The fuel injection system will not be happy with a low temp thermostat.
Click to expand...
the heater core is bypassed I have a stock thermostat I had a 180 in there before I really don't wanna do a heater core the video didn't look fun at all
Mustang5L5 said:
I mean that’s typically what happens. Modern fuel injected engine is designed to run around 200-210 degrees. That’s enough to (almost) boil water.

These engines run efficient at that temp range. I don’t mean fuel economy, but in terms of driving off moisture and contaminants from the oil, proper engine clearances and other factors that contribute to a long-living engine.
Click to expand...
good so it's all good for now thanks everyone
 

7991LXnSHO

wanna catch the space herp
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#15
  • May 20, 2022
  • #15
mattys91gt said:
the heater core is bypassed I have a stock thermostat I had a 180 in there before I really don't wanna do a heater core the video didn't look fun at all
Click to expand...
Is that really what you got out of what I typed? Can you read it again and make sure I’m not having a stroke? I’m sure I thought about helpful information while I poked at my phone.
Thanks!
 
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mattys91gt

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Feb 3, 2022
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May 20, 2022
#16
  • May 20, 2022
  • #16
7991LXnSHO said:
Is that really what you got out of what I typed? Can you read it again and make sure I’m not having a stroke? I’m sure I thought about helpful information while I poked at my phone.
Thanks!
Click to expand...
I'm new to mustang's I'm 40 I always wanted one all my friends had them growing up now I got one 20 years to late lol but I love it nothing beats the sound of a foxbody mustang and any mustang I'm trying to learn and ask questions I confuse my self with what I ask everyone like this vacuum EGR leak I have I can't figure it out fix this problem and u can Pat yourself on back lol
 

7991LXnSHO

wanna catch the space herp
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#17
  • May 20, 2022
  • #17
mattys91gt said:
I'm new to mustang's I'm 40 I always wanted one all my friends had them growing up now I got one 20 years to late lol but I love it nothing beats the sound of a foxbody mustang and any mustang I'm trying to learn and ask questions I confuse my self with what I ask everyone like this vacuum EGR leak I have I can't figure it out fix this problem and u can Pat yourself on back lol
Click to expand...
I’m glad to try to help, especially if I am not typing nonsense. And obviously, so are many others here.
Do you have another thread started on the EGR vacuum leak?
 

mattys91gt

Active Member
Feb 3, 2022
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May 20, 2022
#18
  • May 20, 2022
  • #18
7991LXnSHO said:
I’m glad to try to help, especially if I am not typing nonsense. And obviously, so are many others here.
Do you have another thread started on the EGR vacuum leak?
Click to expand...
yes I get alot of laughs at me cause I just don't understand what part is what I'm at my car have a look I'm sure I blocked off stuff I shouldn't have,so no smog pump new EGR and this vacuum mess you will see
 

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7991LXnSHO

wanna catch the space herp
10 Year Member
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#19
  • May 20, 2022
  • #19
A lot of that stuff was pulled off for track use when I rescued my car. It runs better with it back in place.
It it your car we were seeing this unfortunate problem recently on in another thread?
 
Last edited: May 20, 2022

mattys91gt

Active Member
Feb 3, 2022
391
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Plymouth Massachusetts
May 20, 2022
#20
  • May 20, 2022
  • #20
7991LXnSHO said:
A lot of that stuff was pulled off for track use when I rescued my car. It runs better with it back in place.
It it your car we were seeing this unfortunate problem recently in another thread?
Click to expand...
ya I had alot of message and diagrams sent to me and something's I understood and others I don't this being my first mustang and me watching to many YouTube videos
 
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