When Is Hot Too Hot?

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JTG

JTG

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I took my car (68 Barracuda 340) out for a drive yesterday, the temperature here in Toronto Ontario Canada with humidity was around 95F. I have various gauges in the car, some are factory and others are Autometer, out of habit I always check my gauges, which I'm sure most others on here do, especially with Mopars that have had some modication done to the engine. I realize these types of engines tend to run a bit hotter then stock to start off with, my engine temp. gauge is still the factory one and just to demonstrate in the picture below where the needle was sitting. Is this still considered an acceptable operating range for the car taking in to account the temperature outside.
Just incase, does anyone know where I can purchase a lower radiator hose spring preferably in stainless steel and available on this side of the border.
 

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JTG said:
I took my car (68 Barracuda 340) out for a drive yesterday, the temperature here in Toronto Ontario Canada with humidity was around 95F.
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With very high humidity, no doubt.

I realize these types of engines tend to run a bit hotter then stock to start off with
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Not if they're built and tuned correctly.

picture below where the needle was sitting. Is this still considered an acceptable operating range
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Yes.

Just incase, does anyone know where I can purchase a lower radiator hose spring preferably in stainless steel and available on this side of the border.
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The spring is not needed -- it was to permit the fast-fill system in place on the assembly line. It serves no purpose once the car is off the assembly line; if your lower hose is collapsing it's because your radiator is badly clogged, not because you lack a radiator hose spring.
 
Thanks Dan, I should be good then considering the radiator is new. I will assume the last line just before the H on the gauge would be considered, pull your car over to the side of the road as soon as possible.
 
High humidity ACTUALLY helps cooling because it increases the heat exchange of any air heat exchanger

Stock gauges are notoriously "uncalibrated." Until you really know what the temp is, you are just guessing

Stainless steel spring? Thrash around the hardware stores for some steel wire, or maybe some welding filler rod?? and wind your own. All you need is something like a broom or shovel handle
 
Already have three Autometer gauges mounted under the dash and another in the center of dash, running short on places to put another gauge.

Car does run hotter on humid days and also in stop and go traffic. On days with less humidity the needle will sit a notch back towards the C.
The hooker headers let off alot of heat and probably also contribute to a hotter operating temperature.
 
I wondered the same thing. I have a hand held Temp Gun in the trunk that I point at various parts of the engine and radiator when I get a different than "normal" reading from the temp gauge. I now know pretty accurately what degrees the notches on the stock type gauge really are.
 
JTG said:
...Car does run hotter on humid days...... On days with less humidity the needle will sit a notch back towards the C...
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Sorry but regardless of the problem at hand, this is physically and scientifically impossible.

HUMID air accepts more heat. It is just that simple.

Google "specific heat" and "enthalpy."
 
67Dart273 said:
Sorry but regardless of the problem at hand, this is physically and scientifically impossible.

HUMID air accepts more heat. It is just that simple.

Google "specific heat" and "enthalpy."
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Not saying your wrong, just stating through observation inregards to what my car is exhibiting on humid and non humid days via the temperature gauge. Sorry just going by what my eyeballs see.
 
Also some help to clarify, does a modified street engine run a bit hotter then a 100% stock engine, slantsixdan has already expressed his opinion about this, just curious on other members thoughts on this. Just trying to determine that maybe a car with headers and some engine modification will always be expected to run a bit hotter then stock.

Seabee what degree temperature would you say the gauge I have pictured is at?
 
A larger/ modified/ higher HP engine HAS to put out more heat, it's a simple matter of thermodynamics. Now, whether the EXISTING cooling system is capable of staying "with" that increase is the big big question.
 
67Dart273 said:
A larger/ modified/ higher HP engine HAS to put out more heat, it's a simple matter of thermodynamics. Now, whether the EXISTING cooling system is capable of staying "with" that increase is the big big question.
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Due to modification, I've tried to cover all heat related areas during this build, new three core rad, high flow Milodon water pump, heavy duty oil cooler and heavy duty tranny cooler. Specs: 340, x-heads with 520 lift and 3500 stall and 750 holley dp, torker 2 intake, hooker headers, 3.91s in the back. Maybe my car is running at ideal operating temperature for what it is and I'm just over reacting.
 
250 it is time to shut it off get a good thermometer gauge and stick it into your radiator and gauge your gauge from the reading the thermometer shows you should be good 220 230 is fine 240 think about it`s 250 shut it off and let cool off.
 
My 2 cents... check or change your radiator cap. It has to hold pressure. You cannot tell by looking at them. My a-body was running hot only on hot days and it turns out the cap was only holding about 8 lbs.
 
cudajim said:
My 2 cents... check or change your radiator cap. It has to hold pressure.
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…Unless, like me, you're running waterless coolant, in which case the cap needn't hold any pressure at all because the stuff won't boil at any temperature your engine can actually reach. See here, here, and here for discussion and here for the company's website. It is costly but beneficial -- not only in terms of engine-cooling performance, but when there's no water in the cooling system there's no corrosion, and when there's no pressure in the cooling system all the hoses, solder joints, seals, and gaskets are under a great deal less stress. Works well fer me.
 
mine never goes over the third marker on the gauge and that was yesterday in 95+ in bumper to bumper traffic ., yours is on the fifth . Seems a bit on the hot side to me(over 1/2 way on stock gauge = start to worry imo) , but I'm no expert . I would get another gauge to check actual temp . 190-225 is all right , 235 above and it's time to have cooling system checked .
I have 30 over 10.5-1 pistons cam a touch less lift than yours close to stock converter 3:73 gears , hedman tight tube headers , air gap intake with factory rad shroud and clutch fan . Running 50/50 anti freeze water .
 
When the block drools into a puddle of goo on the ground under the front of the car, it's too hot.
 
This thread started 07-06-2011, 01:53 AM when it was temperature in Toronto Ontario Canada with humidity was around 95F. It would be pretty good assumption that it isn't 95F there now. Are we going to have my air conditioning don't work thread by a member at the north pole brought back up in the next month?

Some people need to pay attention to thread dates and details before draging it back to the top.
 
Oklacarcollecto said:
This thread started 07-06-2011, 01:53 AM when it was temperature in Toronto Ontario Canada with humidity was around 95F. It would be pretty good assumption that it isn't 95F there now. Are we going to have my air conditioning don't work thread by a member at the north pole brought back up in the next month?

Some people need to pay attention to thread dates and details before draging it back to the top.
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Exactly why I gave the answer I did. lol
 
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