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What is the optimum operating temperature for engine?

  • Thread starter Thread starter 65 fastback
  • Start date Start date Jul 14, 2009

65 fastback

Founding Member
Mar 17, 2002
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Northern VA
Jul 14, 2009
#1
  • Jul 14, 2009
  • #1
At what temperature should I set my new electric fan to come on? I have a 180* T-stat, so I was thinking I should set the fan to come on at 190 or 200.

Tim
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Jul 14, 2009
#2
  • Jul 14, 2009
  • #2
I knew one of the engineers who worked on engines for Ford, and he told me they were intended to run best with a 190° thermostat. I like to use the genuine Ford unit, very high quality and has bleed air valve which eliminates all those problems bleed ing the air out of the system.
 
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D.Hearne

New Member
Sep 29, 2000
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south louisiana
Jul 14, 2009
#3
  • Jul 14, 2009
  • #3
Run whatever T-stat keeps it in the 180-210 range. The exact T-stat rating will not always do the job in keeping the temps where you want em. Start with a 180*. If it runs hotter, try a 160*. If too cold then try a hotter one.
 

rbohm

Founding Member
Apr 12, 2002
6,698
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tucson,az
Jul 14, 2009
#4
  • Jul 14, 2009
  • #4
i would set the fan to come on at about 205-210 degrees and off at 185. keep the tstat you have now as it will work just fine with an electric fan.
 

wicked93gs

15 Year Member
Sep 30, 2006
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93
Nashville TN
Jul 14, 2009
#5
  • Jul 14, 2009
  • #5
for me I like my fan on at 195 and off at 190...my preference...190-195 is the ideal temperature for gas mileage...anything over 170 is ok(as long as its not too hot of course)
 
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dinger2

New Member
Nov 1, 2004
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Jul 15, 2009
#6
  • Jul 15, 2009
  • #6
Where are you finding these ford stats with the bleed hole. I can't locate anything like it even when searching for ford OE stats? Any links?

Thanks
 
D

D.Hearne

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#7
  • Jul 15, 2009
  • #7
You can make your own, just drill a 1/8" hole in the upper flange (as it sits in the housing)
 

brianj5600

Active Member
Sep 19, 2003
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Middle TN
Jul 15, 2009
#8
  • Jul 15, 2009
  • #8
My thermostat housing has about a 1/2" bypass hose on it. What will adding a hole in the t-stat do? I thought that was a chevy mod.
 
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D.Hearne

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Jul 16, 2009
#9
  • Jul 16, 2009
  • #9
It lets any trapped air out into the upper hose
 

Decurion

Member
Sep 28, 2006
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Livonia, MI
Jul 16, 2009
#10
  • Jul 16, 2009
  • #10
No need for a bleed hole when you use a vacuum venturi cooling system refiller. Matco #mcr101. It pulls the cooling system down to about 26" vac, then flip a valve and use the vacuum to pull the coolant in. Thats it, no more bleeding the system. Its not really a necessity on older cars, but starting in the 90s cooling systems started getting pretty complex which makes them impossible to bleed the old fashioned way. I vote for a 180* stat, fan on at 195, off at 190.
 

rbohm

Founding Member
Apr 12, 2002
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tucson,az
Jul 16, 2009
#11
  • Jul 16, 2009
  • #11
wicked93gs said:
for me I like my fan on at 195 and off at 190...my preference...190-195 is the ideal temperature for gas mileage...anything over 170 is ok(as long as its not too hot of course)
Click to expand...

Decurion said:
I vote for a 180* stat, fan on at 195, off at 190.
Click to expand...

my problem with such a narrow range is that the fan is constantly turning on and off, and that is hard on the fan and the relay(you ARE using one right?), and it doesnt give the fan motor time to cool off a bit before it is running again. a wider range like i suggested gives the fan motor time to cool a bit before turning back on, and it takes the constant on and off loads away.
 
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D.Hearne

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#12
  • Jul 16, 2009
  • #12
If you can fit a big enough radiator, you can damn near eliminate the fan's function. But that's a bit hard to do in most cars.
 

jcp123

New Member
Nov 1, 2003
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Tyler, TX
Jul 18, 2009
#13
  • Jul 18, 2009
  • #13
180-190 is probably an optimum mix of economy, performance, and longevity. The hotter the better the fuel economy, but running colder doesn't necessarily better your performance.
 

blown65

Founding Member
Jul 7, 1999
1,938
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Queen Creek Arizona
Jul 18, 2009
#14
  • Jul 18, 2009
  • #14
jcp123 said:
180-190 is probably an optimum mix of economy, performance, and longevity. The hotter the better the fuel economy, but running colder doesn't necessarily better your performance.
Click to expand...


Besides EFI, why would running an engine hotter equal more hp and better performance? From 130 or so degrees to an engine temp of 160 on my car is a loss of about a tenth in the 1/4 mile. Hell, there are guys that run ice to cool thier cars, have flush kits to cool them down. They must be crazy!
 

jcp123

New Member
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Jul 18, 2009
#15
  • Jul 18, 2009
  • #15
Nope, hotter just enhances fuel economy, for the same reason it hurts performance. Thinner air. Didn't mean to imply otherwise. Cooler, depending on the oil, though, can mean it's thicker and hold back performance (somewhat - the difference may be academic). The secret is to keep the air charge cool, even if the engine's running warm, if you're chasing power, where a warmer air charge is in your interests for fuel economy.
 

blown65

Founding Member
Jul 7, 1999
1,938
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39
Queen Creek Arizona
Jul 18, 2009
#16
  • Jul 18, 2009
  • #16
jcp123 said:
Nope, hotter just enhances fuel economy, for the same reason it hurts performance. Thinner air. Didn't mean to imply otherwise. Cooler, depending on the oil, though, can mean it's thicker and hold back performance (somewhat - the difference may be academic). The secret is to keep the air charge cool, even if the engine's running warm, if you're chasing power, where a warmer air charge is in your interests for fuel economy.
Click to expand...

no problem, not picking on you directly. I see this posted now and then on here by others and it drives me nuts. LOL

On the street I have a fan switch that lets mine heat up, but at the strip I always go faster the cooler I get the motor. Cold engine Hot oil.
 

jcp123

New Member
Nov 1, 2003
408
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0
Tyler, TX
Jul 18, 2009
#17
  • Jul 18, 2009
  • #17
blown65 said:
no problem, not picking on you directly. I see this posted now and then on here by others and it drives me nuts. LOL

On the street I have a fan switch that lets mine heat up, but at the strip I always go faster the cooler I get the motor. Cold engine Hot oil.
Click to expand...

You're good cold engine, cold air, hot oil. A good combo for the strip!
 
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