[gearheadslife]

Originally Posted by T-bucket23

There is more bad information in this thread than good. If you take a black part a white part and a green part that are all made from the same material and heat them in the oven to 350, take them out, keep in the dark and check the temperature on all in 15 minutes there will be no appreciable difference.
The color in relation to the temperature of the part has to do with its ability to absorb energy from light.

wrong,, bake a pie/cake/bread in a black pan and a white one.. one will take 10-15 minutes longer..

[poncho62]

years ago I was informed that cheapo chrome thermostat housings were crap and never sealed right.....I think this is where all this is originating.

[cobalt327]

I thought there was a reason automobile radiators were always given a thin coating of black paint... besides looks.

[T-bucket23]

Originally Posted by gearheadslife

wrong,, bake a pie/cake/bread in a black pan and a white one.. one will take 10-15 minutes longer..

You couldnt be more wrong. Color has nothing to do with it, also never saw a cake pan that was painted. Remind me no to eat at your house.

[T-bucket23]

Originally Posted by cobalt327

I thought there was a reason automobile radiators were always given a thin coating of black paint... besides looks.

Everything in the car that is not body color or chrome is black so it will be hidden and not ruin the looks of the car. Imagine if the inner fenders and frame and other items were white how bad they would stick out.
As a side note paint on anything decreases its ability to dissipate heat. Acts like a blanket.

[MARTINSR]

This is a damn interesting discussion, I am going to have to do a little experiment, don't know when, I'll have to put a note up on the wall in the garage to remind me so I don't forget when I get a chance to do something to test this. I too have always been told about painting anything that you want the most heat dissipation you can get, paint it black, flat black. This goes for transmissions as well as radiators, "there is a reason they paint them black" was the answer when asked years ago. Polishing the trans body retains heat because it isn't porous anymore, this makes sense. So a "porous" black paint made sense to dissipate heat. But this thread has gave me a serious "hmmmmmmm moment.

Brian

[cobalt327]

Originally Posted by T-bucket23

Everything in the car that is not body color or chrome is black so it will be hidden and not ruin the looks of the car. Imagine if the inner fenders and frame and other items were white how bad they would stick out.

Olds W-30:

As a side note paint on anything decreases its ability to dissipate heat. Acts like a blanket.

That's not entirely true. Not here to argue though, so that's all I have to say.

[DanielC]

Does somebody have an engine with an oil temperature gauge? And want to do an experiment with chrome VS. painted valve covers, and oil pan?

Heat moves in three ways. Conduction, convection, and radiation.
Conduction happens with direct contact, or heat travelling through a material. Conduction is what happens when you try to weld aluminium, and as you get close to welding temp, the whole part just melts.
Convection is what happens when the baseboard heater on one side of a room heats the whole room. The air by the heater is heated, expands, rises, and moves across the ceiling, and cold air from the other side of the room takes its place.
Radiation is the heat you feel from a campfire, even though the smoke is going up. This is heat you feel standing close to headers on a just ran car.

Like I said before, the color or type of coating on engine parts should not have a significant difference on the water temperature. The thermostat, and radiator should control the water temp. if it does not, you have other problems.


Where valve covers, and oil pans can influence temperature is in the oil temperature. The oil does a lot of the cooling of the engine, especially the internal parts, like bearings, pistons, and any other parts not in direct contact with the engine waterjacket. Oil temp is not monitored in most cars, so most people would not ever know what difference coatings on external engine parts make.

I have ran a oil temperature gauge on an Air cooled VW engine on a tube frame sand rail. To be honest, the only time I saw the engine oil temp even come close to 200 degrees, F was when a rag covered part of the external oil cooler, I had mounted just outside of the cooling air intake on the engine.

[tnovot]

Originally Posted by T-bucket23

There is more bad information in this thread than good. If you take a black part a white part and a green part that are all made from the same material and heat them in the oven to 350, take them out, keep in the dark and check the temperature on all in 15 minutes there will be no appreciable difference.
The color in relation to the temperature of the part has to do with its ability to absorb energy from light.

Amen! I agree that some of the bad info regarding this topic is due to confusion with the rate and amount of heat absorption from sunlight. It makes no sense that the color outside of an object can affect the amount of heat radiated from within.
Terry

[MARTINSR]

It's so funny I asked my sweet wife about this subject and she looked at me and said "It's under the hood protected from any sun what difference could color make?"

Brian

[gonzo08383]

the only thing i can think of would be a performance water pump(high volume) being chrome would make the engine run hot. not because of the chrome but because high volume water pumps are meant to be under-driven to free up hp and still flow enough to cool. i didnt under-drive mine and the coolant flowed too fast and the motor ran at 210*. the only rationale i can find is that someone figured their chrome hv pump was making the engine run hot because it was chrome. you ever see full-out chrome big blocks in the hot rod mags? they don't have any trouble so i'm sure you won't either.

[oldbogie]

Originally Posted by MalibuMike

I'm building a 454 bbc & I've just started ordering parts for it & I was looking to dress the motor up alittle with some chrome pieces (intake, carb, valve covers, etc) but was informed that chrome engine parts draw more heat, is this true?

Well there's some old sayings about this; "Chrome Don't Get Ya Home" and "If It Don't Go, Chrome It.

Basically polished surfaces don't radiate heat well, this includes chrome. To a large extent it depends on whether you're building for show or go. The go guys looking for every edge don't use chrome or polished surfaces as they reduce heat transfer which can be a problem epecially on an endurance engine where it's expected to deliver a lot of power for a long time and becasue of aerodynamic qualities, the radiator size is just enough to do the job and no more. For an average street driver, or drag racer, either the time at temp isn't enough to be critical or the increased amount of temp dumped into the cooling system is inconsequential.

So let your end use be your guide.

Bogie

[496CHEVY3100]

Originally Posted by gonzo08383

the only thing i can think of would be a performance water pump(high volume) being chrome would make the engine run hot. not because of the chrome but because high volume water pumps are meant to be under-driven to free up hp and still flow enough to cool. i didnt under-drive mine and the coolant flowed too fast and the motor ran at 210*. the only rationale i can find is that someone figured their chrome hv pump was making the engine run hot because it was chrome. you ever see full-out chrome big blocks in the hot rod mags? they don't have any trouble so i'm sure you won't either.

Those all chromed out big blocks will not run hot only running the few seconds it takes to load or unload off the trailor that their (street driven ) cars were delivered in ,just a note my Harleys engine cases and cyl jugs are crinkle black from the factory ,presumably to lower heat,cannot say if it works or not