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Posted by: retrofit Jul 9 2007, 11:51 PM

Is there any evidence that painted EFI intake tubes will make the engine run hotter/cooler depending on the color?
Over at 914 groups someone posted that when he painted his intake tubes black the engine ran 20* hotter.
So if you paint the tubes a light color (reflective, not absorbing heat?) it will run the same or, cooler?
I have seen nicely detailed engine bays where the plenum and intake was painted the body color. Could this be a functiional mistake?

Posted by: Dan (Almaden Valley) Jul 10 2007, 12:14 AM

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Posted by: messix Jul 10 2007, 12:19 AM

DUH! yellow is faster!

i doubt it would make any measurable difference.

Posted by: Johny Blackstain Jul 10 2007, 07:17 AM

Does'nt make sense to me. How could black affect the engine temp... there's no light in there? Color affects temp on a visual basis, not a mechanical one. Put a black 914 & a white 914 in the sun the black one will get hotter. Put them in the shade & the temp stays the same. Perhaps it was the content /makeup of the black spray paint he used? No insulation value from the engine heat?

Posted by: Krieger914 Jul 10 2007, 08:41 AM

From the factory they are painted. Maybe someone ceramic coated them. Oh but that would keep heat out, as the runners are bolted to the heads with a plastic block insulating between it and the head. Horsecrap, oh wait maybe he forgot those phenolic blocks/spacers when he reinstalled.

Posted by: toon1 Jul 10 2007, 11:35 AM

the person who stated that needs to put down the crack pipe and step away from the keyboard.

I noticed my car ran cooler when I replaced the muffler bearing

Posted by: SirAndy Jul 10 2007, 11:49 AM

yes. flat black is the worst as it absorbs heat much better than, let's say a bright and shiny white ...

flat black runners will get warmer by absorbing more heat from the engine compartement ...
Andy

Posted by: SirAndy Jul 10 2007, 11:52 AM

nice try, but no dice ...

heat *is* light. just because YOU can't see it doesn't mean it isn't there. your (mine, humans in general) range of vision is very limited. there's much more light than what *we* can see.

flat black does not care about what you or i can see. it'll absorb surrounding heat much better than a lighter color ...
Andy

Posted by: So.Cal.914 Jul 10 2007, 12:05 PM

Good response, interesting point.

Posted by: Demick Jul 10 2007, 12:05 PM

Andy is right.

In theory, the black runners will absorb more heat. But in practice, you will not see a measurable difference in engine or intake air temperature based on the color of the intake runners.

Posted by: toon1 Jul 10 2007, 12:16 PM

If i put two parts in an oven, one white and one black, and turned the oven to 140* (engine bay temps)you are telling me the black part would be hotter!?

Keith

Posted by: brer Jul 10 2007, 12:24 PM

heat is radiation.

I believe they were painted a lighter color intentionally, and should not be painted black, but light grey or even white.

they reside over the black cooling tins which give off a large amount of radiant heat.

flat black has a 1:1 absorptance/emmittance ratio meaing it absobs as much as it gives off.

white on the other hand is 1:4 ratio meaning it gives off 4 time more than it absorbs which translates into a REAL WORLD decrease in its working temp.

Its known as "temperature of equillibrium"
this is measureable stuff not theory.

Posted by: brer Jul 10 2007, 12:26 PM

the black part will reach temp faster.

equillibrium has alot to do with exposure.

Posted by: SirAndy Jul 10 2007, 12:38 PM

simple physics ...

Posted by: toon1 Jul 10 2007, 12:45 PM

interesting, good thing I am gong with chrome P coat on my intake runners. Not only will they run cooler ,my car will go faster

Posted by: Demick Jul 10 2007, 01:08 PM

Once again, yes the black runners will absorb more heat.

But the question was, does the paint color make a real difference to engine or intake air temperatures. To answer this, the question becomes, how much more heat will the black runners absorb?

Within the engine bay, and given the area of each runner, I would estimate that we are talking about less than 2 watts of power (per runner) difference between black and white runners (really I think it's less than 1 watt).

Anyway, the runners have relatively cool air running inside them. A 2L engine at 3000 rpm pulls around 50 CFM of air through each runner. With this volume of air, it will take ~16 watts of power to heat that air by 1 degree C.

So you can see that at 2 watts, or even 5 or 10 watts difference, you would only be heating the intake air by a fraction of a degree.

Hence, paint your intake runners any color you want.

Posted by: brer Jul 10 2007, 01:28 PM

the radiant source is the engine tin which is signficantly hotter than the engine bay temp especially sitting in traffic.

sitting at idle in traffic I would wager your pipes would get rather hot, so why speed up the process ?

just my opinion, feel free to blow up your motor with the wrong color paint.

Posted by: toon1 Jul 10 2007, 01:37 PM

blow up your motor with the wrong color paint!!!

Posted by: Demick Jul 10 2007, 01:38 PM

Wow. This thead has taken an interesting turn.

The factory decided to put the stock 2L engine air intake in a location where it draws in air that is more than 50 degrees F hotter than the outside air.

Yet, apparantly, they also painted the intake runners a light color to prevent further heating this air by a fraction of a degree. And this fraction of a degree will blow up your motor if you paint your intake runners with the wrong color!

Posted by: toon1 Jul 10 2007, 01:45 PM

the question was, would you see hotter head temps with intake runners any other color than stock grey. I think the answer is NO!

blow up your motor with the wrong color..... classic!!!

Posted by: brer Jul 10 2007, 01:46 PM

thats called sarcasm.

Posted by: toon1 Jul 10 2007, 01:49 PM

I know, it was great!!!!

Posted by: brer Jul 10 2007, 01:52 PM

phew, recovered on that one.

Posted by: SirAndy Jul 10 2007, 02:02 PM

i wonder if they were trying to match the intake air temperature to the fuel temperature at the injectors.
for perfect mixture and efficiency, you know ...

after all, the fuel rubber lines are black and the fuel tank is painted black as well! (and that's a HUGE surface area)
Andy

Posted by: Johny Blackstain Jul 10 2007, 02:13 PM

Heat is not light. Light can emit/project heat but where is the light in lets say a chemical hand warmer? Heat, the kind we're talking about- not radiated energy but absorbed, is the excitement of molecules in an object & there are other forms of energy that can excite molecules into a heated frenzy besides light; electricity for one. What color something is only relates to heat within the light spectrum- pour gas all over a white teener & a black teener & I don't think the color will really matter. Put 2 teeners in the sun & the black one will be hotter than the white one, period. We can't see infrared or ultraviolet but how those particles impact onto a surface is still going to be measured within & outside of the visual light spectrum. Cut the light out & that range of heat is removed. As to weather or not flat black absorbs more non-visual heat over white is what did not make sense to me. Poor choice of words on my part before.

Posted by: retrofit Jul 10 2007, 02:17 PM

Ok, how about stripping the paint off down to bare metal, wet sand, buff a bit, then shoot the tubes with clear coat? Get a"natural" industrial look on top of the motor, and efficient temp wise(?)...

Posted by: So.Cal.914 Jul 10 2007, 02:30 PM

Posted by: So.Cal.914 Jul 10 2007, 02:35 PM

This sounds like a mythbusters moment, whos going to volunteer their cars?

Posted by: Johny Blackstain Jul 10 2007, 02:35 PM

- they'd both be @ 140* black or white

Posted by: Air_Cooled_Nut Jul 10 2007, 02:38 PM

The runners are very short and the air RUSHING through them is rather quick so the short answer is "No, runner color doesn't make a difference". If the air had time to 'puddle' in the intake runner one may have a possible arguement.

Posted by: toon1 Jul 10 2007, 02:39 PM

That's asking for some serious trouble!! NOT!

do what you like, it won't affect a thing. there are ton's of things to worry about that will affect engine temps than the color of the intake runners

Posted by: jaminM3 Jul 10 2007, 02:42 PM

If you think about it, in modern cars almost every intake manifold is flat black plastic. I doubt every auto maker in the world is that clueless...

Posted by: SirAndy Jul 10 2007, 02:44 PM

sure it is ...
photons waving through space, occasionally pretending to be particles.
only difference from visible light is the wavelength, amplitude and energy content ...
(note that talking about visible light implies that there also is non-visible light, otherwise that distinction would be useless)

you might want to freshen up on your quantum mechanics basics ...
Andy

Posted by: Johny Blackstain Jul 10 2007, 02:45 PM

Excellent point, they are & they're all under the hood absorbing heat from the engine & not from a light source.

Posted by: Johny Blackstain Jul 10 2007, 02:46 PM

Heat can emit light & light can emit heat but they're called heat & light because they're measuring 2 different things.

Posted by: brer Jul 10 2007, 02:46 PM

but thats plastic dude.
totally different head.

Posted by: SirAndy Jul 10 2007, 02:49 PM

like i said, you might want to walk down to the library and pick up a book on quantum mechanics ...

heat and light are called different things because when man gave them those names they knew nothing about photons or subatomic particles.

the words "light" and "heat" have been around for a long time.
that does not mean anything, as both are man-made distinctions of the same thing, and not a fundamental difference in nature.
Andy

Posted by: por73914 Jul 10 2007, 02:54 PM

Posted by: SirAndy Jul 10 2007, 02:59 PM

again, heat and light are just two different words for the same thing.

electromagnetic radiation

same thing, just different wavelength, frequency, amplitude and thus energy content.
Andy

Posted by: toon1 Jul 10 2007, 03:00 PM

OH boy!, look what you started

Keith

Posted by: So.Cal.914 Jul 10 2007, 03:00 PM

Einstein, paging Dr Einstein...

Those darn teachers said math would save my life someday, should have paid more attention in physics.

Posted by: Johny Blackstain Jul 10 2007, 03:06 PM

& somehow I agree w/ a good part of what you've said. They are man made distinctions of natural energy waves- what we can feel & what we can see. Technicaly if you remove the light spectrum from the equation I would suppose that the flat black finish will still absorb non light particles over the white surface @ a faster rate. But the black pot in the oven actually gets hotter than the white pot? I can buy it will get hot faster but how can it get hotter?
Oh yeah, why don't you mail me a book instead ? My legs hurt & I'm tired of walking right now .

Posted by: SirAndy Jul 10 2007, 03:20 PM

try this one:

The Elegant Universe, by Brian Greene

it has a really good section on electromagnetic waves and how maxwell and einstein and planck eventually figured it all out and established todays quantum mechanics ...

it's all just electromagnetic waves ...
Andy

Posted by: jaminM3 Jul 10 2007, 03:27 PM

Yeah, but if we are talking color, wouldn't they make them out of light gray or white plastic?

Posted by: 914nerd Jul 10 2007, 03:34 PM

I believe the distinction you are looking for is the difference between a photon and a phonon
The phonon is the vibration of a lattice (such as that present in any solid) and is "heat" in that it is representative of the kinetic energy in the material. The interactions with photons can produce more vibrations in the material (and thereby make it hotter)
The heat that you are talking about, though, is the heat being emitted from other parts of the engine bay. That absorbed heat is largely IR radiation.
And Andy, definitely a good book


[/nerd]

Posted by: Johny Blackstain Jul 10 2007, 03:38 PM

Quite frankly I'd paint them pink at this point just to change the subject .

Posted by: por73914 Jul 10 2007, 03:40 PM

I thnk pink would drop the temp by 20 degrees...

Posted by: Demick Jul 10 2007, 03:42 PM

There are many ways to add heat to an object. But for this discussion, lets just consider two: conduction and radiation.

In your oven (or your engine bay), both of these occur. Conduction is when the heating element heats the surrounding air. When the air gets hot, it passes some of it's heat to the object in the oven. Considering only conduction, the color of an object won't really matter. The object will only reach (or come close) to the temperature of the surrounding air. This is how most people think of an oven.

But there is also heat transfer occurring by radiation. Heat is radiated directly from the heating coils to any place in the oven that might absorb it. A black object will absorb this much better than a white object. So the black object will heat up faster, and can actually obtain a higher temperature than the surrounding air.

Does this make sense?

Just go outside and you will realize it for yourself. Go stand in the sun. Your skin temperature will quickly rise higher than the temperature of the outside air. This is because radiated heat from the sun is being absorbed by your skin. And this isn't all because of visible light. Remove visible light from the equation and you still have lots of other frequencies including infrared - which we all know works very well for transferring heat via radiation.

In reality, I don't think that conventional ovens do much heat transfer by radiation - but it is there. In contrast, a toaster oven does a large percentage of it's work by radiation. That's why you can cook a turkey pot pie in a toaster oven in under 10 minutes, but it still takes 20 minutes in a preheated oven.

Posted by: brer Jul 10 2007, 03:45 PM

pink is definitely hot.

Posted by: Johny Blackstain Jul 10 2007, 03:50 PM

I thought this was my point? Color is relative to radiation, not conduction. However as Andy has so eloquently pointed out these are man made distinctions of electromagnetic energy. Take radiation out of the equation & the black pot still heats up faster than the white pot, cools down slower. But I still don't see it getting hotter. The oven is set @140*. It will take the white pot longer to get to 140* but when it gets there the black pot will still be at 140*... no?





BTW- there goes my idea for a pink intake .

Posted by: kwales Jul 10 2007, 04:40 PM

Ya know, there is a reason they paint the top of the space shuttle white and the folding radiators in the cargo bay doors black......

It's done for a reason.....

That's why I'm painting the inside of the manifold black and the outside white and making all my engine tin out of Carbon Carbon so my engine compartment is always cool no matter how hot the engine gets.....

Ken

Posted by: Johny Blackstain Jul 10 2007, 04:50 PM

Lesson learned- never argue Physics w/ a German .


Attention Admins- :whiteflag: is now a needed Smilie.

Posted by: So.Cal.914 Jul 10 2007, 04:56 PM

Posted by: TonyAKAVW Jul 10 2007, 05:46 PM

Well, the truth is that light is the abscence of dark. So really, anything 'radiating heat' is really 'sucking dark.'

So if you want the coolest coating, you have to use a color that sucks dark the most, because as we all know, its very cold on the dark side of the moon. This will give you the most phonoffs (the anti-vibration of a phonon).

Or, you could try blocking the Bloch waves.

-Tony

Posted by: SirAndy Jul 10 2007, 06:13 PM

i tought you can only find those when you throw pebbles in a gravity well ...
Andy

Posted by: messix Jul 10 2007, 07:55 PM

chit !

i swear half of these posts sound like alphy wrote them.

light is less absorbed by some "lighter colors". most visable light doesn't have any heat. only when the "light" excites a surface and cause the suface molucules to excite is it turned in to heat.

put a white pot and black pot in to a oven and as long as both coatings have the same properties except color they both will heat at the same rate.

now if you coated one with a coating of lets say the same stuff the is on the space shuttle [you now those BLACK tiles] that might not heat at the same rate.

'nuff i'm done.

let the nonsense continue.

Posted by: John Jul 10 2007, 08:18 PM

Sorry if this is a repeat, but I couldn't finish reading all the posts before posting....





Heat can be observed through infrared radiation.

Using infrared visualization (a camera or other means), heat can be seen. In an infrared heater, the reflectors (which direct the infrared radiation) are shiny and bright. The reflectors loose efficiency when they become dirty and are no longer reflective.

Heat is energy and always will give off infrared radiation. Sometimes the heat can give off light waves that are in the visual spectrum that can be seen by the human eye, but more often it is in the infrared spectrum.

Just because you can't see it, does not mean that it is isn't there.

The Infrared spectrum of wave forms acts just as the visible spectrum. I.E. bright objects tend to reflect and dark objects tend to absorb.

You can believe what you want, but if you want to live in reality, you will accept facts.

Posted by: John Jul 10 2007, 08:27 PM

Geez, I almost forgot.

For all practical purposes, it will not matter what color you decide to paint your intake runners.

Your car is doomed to live out eternity on jackstands.


(Besides, once all the engine compartment comes to equilibrium, the color will matter not.)

Black bodies will heat faster and dissipate heat faster (but only due to radiation).

Posted by: Cap'n Krusty Jul 10 2007, 08:28 PM

"Just because you can't see it, it's there"? Hmmmmm ............................
Therefore, it's there because you can't see it? I LIKE that! Does it follow that if you CAN see it, it's NOT there? This is getting FUN! Glad I paid attention in things like Geometry and Philosophy ............ The Cap'n

Posted by: John Jul 10 2007, 08:32 PM

I have no clue what you are talking about

Posted by: Johny Blackstain Jul 10 2007, 08:35 PM

So Andy, what would you like to argue about tomorrow, since our discussion seems to have generated so much interest ?

Posted by: Dan (Almaden Valley) Jul 10 2007, 08:36 PM

Andy likes to discuss cantilever slicks on 8" wheels

Posted by: Pat Garvey Jul 10 2007, 09:04 PM

Exactly!

Why not simply repaint them to original specs? Dd the origional engineers really wan them to be that ugly? Doubt it. At light, semi flat, they are designed to neither absorb, nor dissipate heat (to any degree). So, why not put them in the condition the engineers deemed best?

I'll go out on a limb here & say that I ONCE had a set chromed! Huge, HUGE mistake - sucked up heat so badly that there was no way to tune the injection. Tried about a dozen times before I put them in the trash (Oh, they were gorgeous!). They were unusable, and unsalable - junk!

Guys - paint 'em the way the were meant to be.
Pat

Posted by: porschecb Jul 10 2007, 09:07 PM

Try this! I do not drive my car much but I use dry ice caplets inside copper tubing it lasts for days and is easy to refill! Cools my engine where ever I need cooling! Short trip/long trip it does not matter! Intake is the best!

Posted by: Cap'n Krusty Jul 10 2007, 11:00 PM

I don't either, but this is almost more fun than I can handle .............. The Cap'n

Posted by: por73914 Jul 11 2007, 06:42 AM

If I paint my air cleaner white would I have cold air induction? I wonder if that would offset the black runners?

Posted by: orthobiz Jul 11 2007, 08:06 AM

Pink intake sometimes raises my temperature...

Paul

Posted by: Scott Schroeder Jul 11 2007, 10:24 AM

based on this thread, I realise how much I did not pay attention in science class. However, you all did make is easy to decide on what color the intakes should be painted...........

Posted by: Johny Blackstain Jul 11 2007, 02:55 PM

Bingo!

Posted by: 914nerd Jul 11 2007, 04:17 PM

What, no pink?

Posted by: Brian Mifsud Jul 11 2007, 04:45 PM

Fellas,

The Elephant in the Room that no-body is mentioning is that Air Cooled thing again... The Amount of heat transferred from engine tin or intake runners Radiated (because or inspite of pigment), is MAGNITUDES SMALLER than the heat transferred by the air flow.

You want COOL intake runners???... You already HAVE THEM.. they are ALUMINUM, and are in intimate contact with flowing engine room air, AND the air cooled heads. If you really want to enhance the cooling, machine the semicircular contour of the Intake Runner OD into some finned aluminum stock, and Solder/Weld on.

or.. Spray alcohol/water on the pipes....

or

Sewer Pipe from Front Right Headlight through the passenger bay and into the engine bay will make the biggest and most significant difference.

Posted by: brer Jul 11 2007, 05:12 PM

black intake runners will run hotter.

Posted by: TonyAKAVW Jul 11 2007, 05:35 PM

green yellow and black = Cool Runnings.




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Posted by: BiG bOgGs Jul 12 2007, 06:59 AM

With all of this wondedrful quoting of theory how about some numbers. I have heard that Harley riders have noticed that engines painted black run cooler than similar engines painted other colors or even not painted at all. I suggest checking with your local Harley shop, or try out some biker message boards and see what their experiences say. You could probably even get a local bike shop to test this out with an infrared thermometer on some of their different bikes and see if there is an link between color and temp ranges. Remember, the bigger the sample size, the more likely the results represent a correlation or not.

Posted by: por73914 Jul 12 2007, 07:12 AM

What are we talking about?

Posted by: SirAndy Jul 12 2007, 10:33 AM

a engine painted black will radiate more heat, thus running cooler.
Andy

Posted by: toon1 Jul 12 2007, 10:56 AM

what about painting the cylinders black with some motorcycle engine paint? what about the case for that matter?

Posted by: brer Jul 12 2007, 11:11 AM

the dominant heat source in an engine environment is best black. Oil coolers, radiators and such are black because black has the highest emittance value.

Cylinder head tin is black because it needs to shed heat as much as possible.


An object in direct proximity to these primary heat source should not be black unless you want them to absorb the heat being emitted.

Paint them a color that is less absorbtive.


Simple.


Harley engines are best black because the cylinders and heads are primary heat sources. The carbs are not black though.






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Posted by: Brian Mifsud Jul 12 2007, 11:58 AM

Academic Masturbation...



Okay okay.. maybe it's not Academic... but I've always wanted to work that into a conversation somehow!!

Harley Engines are black because the fins are made of CAST IRON.

If you built a 914 engine using Nikasil Cylinders (aluminum fins), would you then INSULATE them by painting them with black paint?? (Or Black Anodize???)

Did Porsche MISS a huge cooling opportunity by NOT painting their crankcases and Aluminum Cylinder Fins BLACK on all their air cooled cars????

My assumption is that Porsche was/is known for being meticulous in their engineering.. YES you may radiate a couple more Watts to the Line-OF-Site HOT ASPHALT PAVEMENT.. but maybe it will backfire on you and ABSORB just as much heat or MORE!


Radiating to the sheetmetal serves little purpose as its only avenue to shed heat is via the high velocity air flowing over it, which is already in intimate contact with the cylinder fins.


IMAO (A for "Arrogant" as most engineers are labeled when spouting off)....Radiating heat is for Space Craft where there is no other means. It is a very crappy way of moving heat, but you have no choice there.

Posted by: rhodyguy Jul 12 2007, 12:35 PM

non oem intake gaskets for 1.7/1.8. pelican, 022 129 707F, $8.75.

k

Posted by: rhodyguy Jul 12 2007, 12:36 PM

non oem intake gaskets for 1.7/1.8. pelican, 022 129 707F, $8.75.

k

Posted by: Johny Blackstain Jul 12 2007, 01:15 PM

Umm, didn't Harley go to Porsche & have them redesign their engine because Porsche was good/experienced at converting air cooled engines to water cooled? I would think that would say enough about if they know how to cool something the right way or not.

Posted by: rhodyguy Jul 12 2007, 01:22 PM

if one wanted to go to the exspense of having the runners thermal barrier coated, i don't think it would hurt. about the same price as powdercoating.

k

Posted by: brer Jul 12 2007, 01:23 PM

Nobody is saying to paint your aluminum cylinders Brian.




A good designer considers every decision no matter how trivial.
But then again, maybe they picked black because its sophisticated and elegant.

Gray does look cool in that spot too.

Posted by: jaminM3 Jul 12 2007, 01:32 PM

Ya think maybe harley did it for asthetic reasons?

I think everyone is overthinking this. It won't make a measurable difference. The airflow and materials are more important.

Just paint the $*(#$% runners any *$%& color you want...

Posted by: por73914 Jul 12 2007, 01:33 PM

Just put some paint on there and let us know how it goes

Posted by: brer Jul 12 2007, 01:52 PM

you guys are ruining the fun by making it simple.

Posted by: por73914 Jul 12 2007, 02:01 PM

How about gold leaf like the F1 Hows that for not so simple?


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Posted by: brer Jul 12 2007, 02:11 PM

Posted by: Brian Mifsud Jul 12 2007, 02:51 PM

Yes, if given unlimited freedom, $, and time. A good employer (i.e. somebody who is trying to make money ((Like Porsche)), will hold a gun to that designer's head with the instructions to get the most bang for the buck, and get on with it.

If the color of mechanical components contributed to a significant heat transfer such that efficiency was improved, they would have done it. If it had, we would all be running around with black cylinder heads as they are the achilles heal thermally to these engines.

Okay, I'm done, I'm puting it back into my pants and zipping up!

P.S. I do like the color "machine grey" for intake pipes. They can get dirty and it isn't as noticeable as it would be if it were a light.

Posted by: BiG bOgGs Jul 12 2007, 09:10 PM

Come on guys! Quit it with the IF IT WORKED it would be done stuff.

IF marketing didn't work, we would do things on what is best, not what is popular.

Just try different paints and see what the results say.

Posted by: flesburg Jul 12 2007, 09:29 PM

I am not an engineer, let alone one who understands thermal stuff,

But in a book I read about Dr. Porsche, he designed an air cooled diesel engine for a tank. He chose air cooled rather than water cooled because it suffered less power loss as it gained temperature and was more consistent in output, AND he could ENCLOSE it in armor. He said he could not do that with a liguid cooled engine for several reasons. I cannot remember them all but one had to do with the location of the water radiator which HAD to have airflow, and another was its variation in efficiency as it heated and cooled with a constantly cycling flow of water of a constantly cycling temperature.

In other words, and air cooled engine could be designed to operate in an enclosed box, or nearly enclosed box and it would somehow reach equilibrium and operate efficiently. He never did say the color of the paint on the tank had any effect.

Come on all of you thermal engineers, tell us we can paint our intake runners red if we want to....without any reason to worry.