Engine Engine Bay crazy hot!

R82148V · Aug 28, 2023

So I noticed that whenever the car is driven then parked, when you open the hood a wall of heat comes barreling out.
There is no way you can touch the upper intake or really anything for that matter for a while after turning the car off.

I'm running a 2 row 2" aluminum rad w/ a 13 lb cap. 192* stat with jiggle pin. I burped the system using a burping funnel. Using the shroud. New stock fan with an HD clutch.
Water pump is brand new. Have both side air deflectors on and the air deflector that going right under the radiator.
The coolant temp is perfect always staying right in the middle no matter if you're driving or stopped.
Upper rad hose is nice, hot and pressurized when the stat opens. There is some coolant expansion in the res so everything is working like it should I think.

Have engine code 11 at KOEO and KOER.
injector balance test comes back as a 9.

I do have shorties on the there using the stock H-pipe.
Exhaust doesn't seem restrict at all. Performed a Vac test and it was 20 at idle and passed all the other vac tests., including the test for a restrictive exhaust.

Is it normal for foxes to be crazy hot under the hood but the coolant temp and gauge to be good right smack in the middle?
Just want to make sure something isn't wrong.

I just recently advanced the timing to 12 - 13 but still running 87 octane. I don't here pinging or anything else. Would / could advancing the timing make it this hot?

Thank you for all your time!!

AeroCoupe · Aug 28, 2023

The thermostat release water to the radiator when it hits 192 deg so the coolant will be hotter than that by the time the t-stat shuts to hold the colder coolant that just got into the engine. The fan is desperately trying to cool the 200 deg fluid in the radiator that is 100 degrees or more than the ambient air. The hot air coming off the radiator is heating up everything under the hood so yes it’s gonna damn hot under there unless you have a heat extractor hood on the car. Even then when you park it now the fan isn’t running and it just has to sit there and cool down to ambient air temp via thermal transfer with little to no air exchange.

I’m not sure what you are expecting otherwise but if you think that Fox Body is warm under the hood crawl around on one of the newer vehicles and it will seem not so bad.

General karthief · Aug 28, 2023

Engine operates at 192-220* in an enclosed box with limited air flow in and out. Park the car and air flow stops, thermal transfer begins raising the under hood temp exponentially. Heat soak is another term.
Think about how hot 192* is, I've heated up soup and sandwiches on a intake manifold while sitting in a parking lot.

limp · Aug 28, 2023

Louvred or vented hoods do wonders for letting out heat....

R82148V · Aug 29, 2023

General karthief said:
Engine operates at 192-220* in an enclosed box with limited air flow in and out. Park the car and air flow stops, thermal transfer begins raising the under hood temp exponentially. Heat soak is another term.
Think about how hot 192* is, I've heated up soup and sandwiches on an intake manifold while sitting in a parking lot.

haha too funny. Ok i’m feeling better about the heat under the hood. Makes sense with what everyone is saying plus it’s a stock non vented hood. I just wanted to make sure that much heat was ok. never thought about how actually hot 192* degrees was. For some goofy reason I felt like that heat coming off the engine was much hotter than the coolant.

R82148V · Aug 29, 2023

limp said:
Louvred or vented hoods do wonders for letting out heat....

they are definitely worth it?

nickyb · Aug 29, 2023

I wired my electric fan to stay on till it hits set temp. So if it's hot when I turn it off the fan moves air till it reaches the turn off temp.I
So newer cars do this, you ever walk past a parked car and the electric fans on with engine off?

AeroCoupe · Aug 29, 2023

The louvered or heat extractor hoods are really for cars that are going to see some abuse like track time. Gets the unwanted uplift off the hood and cools the motor a lot better. Tiger Racing makes a really nice carbon fiber one for about $1300 the last time I looked.

limp · Aug 29, 2023

I bought this truck, not expecting to do a frame off resto, and it came with a louvered hood..
454. Turbo 400 that pulled boats and trailers all over... It never once even tried to get too hot....

Mustang5L5 · Aug 30, 2023

200 degrees in a huge lump of iron. It's gonna take some time for that heat to dissipate. My engine throws a ton of heat and takes forever to cool down after a drive.

R82148V · Aug 30, 2023

Mustang5L5 said:
200 degrees in a huge lump of iron. It's gonna take some time for that heat to dissipate. My engine throws a ton of heat and takes forever to cool down after a drive.

Yeah, You're right. I'm just over thinking / reacting. I've owned this car since 1995. Drove it around for about 10 years, then parked it. It sat for the next 14 years and began to restore it once Covid hit 2019/2020. I don't remember it ever getting this much noticeable heat soak, but it very well could have been. The only thing that I can come up with that you all have been stating is "hot air coming off the radiator is heating up everything under the hood". I'm running a much larger aluminum rad now where before I was just using the stock rad. It makes sense that more hot air is now coming off the rad than before. I gotta try that Soup and Sandwich life hack!

Mustang5L5 · Aug 30, 2023

My engine runs right at 180-190 degrees, but it feels so HOT and tons of heat comes of it. Meanwhile my modern cars (which all features lots of aluminum) don't seem to throw off that much heat despite running at 200-210 degrees. They also seem to cool off faster and if i pop the hood while running don't throw off as much heat.

I think it's just modern tech making engines more efficient and better at cooling. Our 1960's era dinosaur engines just aren't that efficient. Most of the energy input (fuel) is probably being turned into heat at a higher rate than modern engines which operate at tighter clearances with better components, less internal wear and such.

On a 90 degree day. My fox engine will be up to temp by the time i back out of the driveway and get about 1/4 mile from the house. Meanwhile my SN95 will need about 3-4 miles or cruising at 2-3K RPM before the temp needle starts to move.

Noobz347 · Aug 30, 2023

R82148V said:
they are definitely worth it?

A word of caution about vented/inducted cowl hood on Fox body Mustangs...

The factory hood on a Fox flows from the high-pressure area, at and below the bumper, and is forced through the radiator, and then bails out under the car.

Add an induction hood and it pulls air from the base of the windshield. That air also exits under the car and decreases the flow of air coming through the radiator by adding air mass behind the radiator.

Add a vented or ram air hood and you get the same effect. Outside air allowed into the engine bay decreases the differential between the two sides of the radiator causing a lower portion of that engine bay air to enter through means other than the radiator.

There is a fix for this. That is: increase the differential on both sides of the radiator by increasing pressure in front of the radiator. Do this by increasing the size of your air dam/chin spoiler.

The one I put on my car is one that I reshaped from a factory Bronco. (93, I think it was). There's lots of things you could do though.

R82148V · Aug 30, 2023

Noobz347 said:
A word of caution about vented/inducted cowl hood on Fox body Mustangs...

The factory hood on a Fox flows from the high-pressure area, at and below the bumper, and is forced through the radiator, and then bails out under the car.

Add an induction hood and it pulls air from the base of the windshield. That air also exits under the car and decreases the flow of air coming through the radiator by adding air mass behind the radiator.

Add a vented or ram air hood and you get the same effect. Outside air allowed into the engine bay decreases the differential between the two sides of the radiator causing a lower portion of that engine bay air to enter through means other than the radiator.

There is a fix for this. That is: increase the differential on both sides of the radiator by increasing pressure in front of the radiator. Do this by increasing the size of your air dam/chin spoiler.

The one I put on my car is one that I reshaped from a factory Bronco. (93, I think it was). There's lots of things you could do though.

I see what you're saying. I had no idea the complexity of hood style vs function. Heck I had no idea these fox bodies even used an air dam until I started restoring the thing. From what you're describing with each type of hood, I'd rather have more air flow through the radiator than not. Stocker it is!

R82148V · Aug 30, 2023

Mustang5L5 said:
My engine runs right at 180-190 degrees, but it feels so HOT and tons of heat comes of it. Meanwhile my modern cars (which all features lots of aluminum) don't seem to throw off that much heat despite running at 200-210 degrees. They also seem to cool off faster and if i pop the hood while running don't throw off as much heat.

I think it's just modern tech making engines more efficient and better at cooling. Our 1960's era dinosaur engines just aren't that efficient. Most of the energy input (fuel) is probably being turned into heat at a higher rate than modern engines which operate at tighter clearances with better components, less internal wear and such.

On a 90 degree day. My fox engine will be up to temp by the time i back out of the driveway and get about 1/4 mile from the house. Meanwhile my SN95 will need about 3-4 miles or cruising at 2-3K RPM before the temp needle starts to move.

" My engine runs right at 180-190* , but it feels so HOT and tons of heat comes of it" This is exactly what I'm dealing with and didn't know if that was normal or not.
I know what you mean about modern engines running with hot coolant but engine heat soak cooler.
I also have a 2015 Willys that runs with the temp gauge right in the middle which is about 205*. Open the hood and its not even close to that temp. I mean even the intake is plastic so there is so much less heat soak than our solid metal foxes.

When I pull the fox into the garage after a run, I've been opening the hood and using a large home depot utility fan right at the engine and rad to cool it down.. Even that takes a good hour to cool down. haha

Mustang5L5 · Aug 30, 2023

R82148V said:
When I pull the fox into the garage after a run, I've been opening the hood and using a large home depot utility fan right at the engine and rad to cool it down.. Even that takes a good hour to cool down. haha

I do the same thing. Pop hood and run a fan with the door opened. If i don't do that, the entire garage heats up like a sauna

Engine Engine Bay crazy hot!

R82148V

Active Member

AeroCoupe

lube between the nut and the face. I know my lubes

General karthief

wonder how much it would cost to ship you a pair

limp

wrap a little cheese around it and its a done

R82148V

Active Member

R82148V

Active Member

nickyb

I gotta say i never painted my nuts, Never Ever

AeroCoupe

lube between the nut and the face. I know my lubes

limp

wrap a little cheese around it and its a done

Mustang5L5

That is…until I whipped out my Bissell

R82148V

Active Member

Mustang5L5

That is…until I whipped out my Bissell

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor

R82148V

Active Member

R82148V

Active Member

Mustang5L5

That is…until I whipped out my Bissell

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Engine Engine Bay crazy hot!

Active Member

lube between the nut and the face. I know my lubes

wonder how much it would cost to ship you a pair

wrap a little cheese around it and its a done

Active Member

Active Member

I gotta say i never painted my nuts, Never Ever

lube between the nut and the face. I know my lubes

wrap a little cheese around it and its a done

That is…until I whipped out my Bissell

Active Member

That is…until I whipped out my Bissell

Stangnet Facilities Maint Tech... Er... Janitor

Active Member

Active Member

That is…until I whipped out my Bissell

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