Is chrome hot or what???

[rumble]

The question has come up several times, "does chrome make a stock engine
run hotter"? We're talking temperature naturally, not performance. As you can see from the photos I have several items chromed on my Marauder engine. Why? Well........that's just the way I like it. Today I had the opportunity to do a little research on this subject and I thought I would pass my results on to the members of our site. What I did was take my bone stock MM next to a bone stock none chromed MM and measure the temperature at several of the same spots on both engines for comparison. Please understand, I am not representing this as any sort of scientific controlled lab test but just what I observed. I started out letting both run at Idle for 20 minutes to make sure they reached operating temps and the fans had come
on and the thermostats open. All temps are Fahrenheit. The outside temp was 80 degrees. I used a Raytek Minitemp pyrometer "ray gun" and I tried to take all readings at about 1 foot but most important I tried to make sure
that each comparison reading was at the same distance.

To start, the fenders measured 100 (stock MM) 101 (chrome MM). this was just to see that both were in the sun approximately the same.

The upper part of the radiators when measured through the grill were 112 for the stock MM and 116 for the Chrome MM.

OK now here are the results I saw;
Upper coolant hose at the Radiator 168 stock, 158 chrome motor
Lower hose, approximately at the center of the curve 163 stock, 147 chrome
Upper coolant pipe 174 stock, 135 chrome
Vertical hose to coolant pipe, 163 stock, 157 chrome
Center of intake manifold 124 stock, 116 chrome
Right cylinder head front 159 stock, 126 chrome
Right cylinder head REAR 173 stock, 152 chrome
Please notice how much hotter the right rear runs, no surprise though
Left cylinder head front 160 stock, 129 chrome
Left cylinder head rear 158 stock, 120 chrome

One thing I need to mention that I feel is important is that the stock MM had
20,000 miles on the clock while mine only has 3,000. I am sure that because
of this mine tends to run somewhat cooler. I think it also shows that a coolant system flush and maybe a conditioner is important to our engines.
I guess that my answer to the original question "does chrome make your
stock street engine run hotter" is "Nope, not really and if it does, not so you
can tell".

There ya go my friends.

[rumble]

OOP's, what happened to the pictures?

Here they are,

http://www.mercurygallery.net/uploads/299/chrom_mill2.JPG

http://www.mercurygallery.net/uploads/299/Chrome_mill.JPG


http://www.mercurygallery.net/uploads/299/raygun.JPG

[Mike Poore]

Nice job, Rumble, great post. If anything, it seems the chrome one runs cooler, and looks fantastic to boot. Was it possible to measure the cooling fluid temp? :woohoo:

[SergntMac]

Very interesting data, thank you.

Could you please cover the head temps again? "Right/left" do not help me much, "driver's side/passenger side" explain more.

Thank again!

[rumble]

Very interesting data, thank you.

Could you please cover the head temps again? "Right/left" do not help me much, "driver's side/passenger side" explain more.

Thank again!

Sorry my good friend. To me right, left, front back is always from the drivers seat. Therefore right would be passenger side, left would be the drivers side.

[TheDealer]

I was always told that chrome was not good for racing because it holds the heat in. Maybe that's why the outside temps are lower. I've also been told that polishing aluminum will hold heat in because you are sealing the pours that let it breath. Just what I've been told!!! :confused:

[rumble]

Nice job, Rumble, great post. If anything, it seems the chrome one runs cooler, and looks fantastic to boot. Was it possible to measure the cooling fluid temp? :woohoo:

Yes I did but I neglected to write it down. If I remember correctly
it was 126 or so for both cars at the reservoir. Very good question though.

[Tallboy]

chrome holds in the heat.

[Mike Poore]

I was always told that chrome was not good for racing because it holds the heat in. Maybe that's why the outside temps are lower. I've also been told that polishing aluminum will hold heat in because you are sealing the pours that let it breath. Just what I've been told!!! :confused:
:hmmm: That's interesting, Ray. With that in mind, I guess it's really important to know the fluid temp.

[rumble]

I was always told that chrome was not good for racing because it holds the heat in. Maybe that's why the outside temps are lower. I've also been told that polishing aluminum will hold heat in because you are sealing the pours that let it breath. Just what I've been told!!! :confused:




Ray, I've heard the same thing and my experience with racing engines
was to try and make everything black for heat dissipation, I would think
if that were true here then the hoses would be hotter though.

It may be that the heat retention is much more of a
factor on racing engines than just a stock street motor..

It might be interesting to really flog these cars and then do the checks
to see if we have the same results.

[2003 MIB]

Pics don't do this car justice. I was glad to read the temp. data- interesting stuff but I swear to y'all- you can't imagine how great this Marauder looks under the hood. It's very nice!!!!!!!!!!!

[Bluerauder]

Sorry my good friend. To me right, left, front back is always from the drivers seat. Therefore right would be passenger side, left would be the drivers side.
I thought these references were standard .... :dunno: I have always used rumble's reference system as well. Everything relative to the driver's view.

[TheDealer]

I believe the external temp is lower, but the internal engine temp is higher. As far as hurting anything. I doubt it. My cars have always had chrome galore. By the way, looks GREAT!!! RAY :cool5:

[Petrograde]

Gary,.. looks great! ..and I'm glad to hear those temps aren't too high!!

I know you've told me that your water temp guage hasn't shown much of a heat increase.

I wonder how close the stock temp gauge gets to true temp.?

[rumble]

Gary,.. looks great! ..and I'm glad to hear those temps aren't too high!!

I know you've told me that your water temp guage hasn't shown much of a heat increase.

I wonder how close the stock temp gauge gets to true temp.?

Probably only slightly better than our faux oil pressure gauge. I have noticed no increase whatsoever in the temp gauge reading though. If there is any increase it's less than the gauges ability to measure.

Hey, you ought to like those valve covers, they use to be yours.
My My, what that TAF started.

[Patrick]

Since I am not planning on racing. Maybe 4:10's and a tune and just play around a bit would chrome have any restrictions?

[Krytin]

Try an internet search on "black body radiators" - the chrome finish will transfer heat at a slower rate, at least that's what my H.S. teacher was telling me!
If you're not seeing a significant temp increase for fluids - it looks too good to worry about!

[hdwrench]

Is chrome hotter? I dunno possibly. Does it make a huge difference? I doubt it. 90% of the harley motors you will see are decked out in chrome and they are air cooled.

that being said my HD has no chrome on it.

[Patrick]

Good info thanks!!! Just thinking about dressing her up a bit!

[shannon corkill]

The chome on your Marauder looks great! I as far as does it run hot or not with chrome/polished ,this my take. I started to build my Superbird to run in the lone star classic and heat is BIG issue with superbirds. The problem with chrome and polished aluminum is that it holds the heat in the intake which is bad because you air isn't as dense thus a performance loss. I had a 10-15 degree coolant temp difference between polished and Natural finish intake..Mind you a Bird is a heat monster. I think the chrome look is great, did you think of doing the ceramic coating for a temp barrier instead of chrome?

[rumble]

The chome on your Marauder looks great! I as far as does it run hot or not with chrome/polished ,this my take. I started to build my Superbird to run in the lone star classic and heat is BIG issue with superbirds. The problem with chrome and polished aluminum is that it holds the heat in the intake which is bad because you air isn't as dense thus a performance loss. I had a 10-15 degree coolant temp difference between polished and Natural finish intake..Mind you a Bird is a heat monster. I think the chrome look is great, did you think of doing the ceramic coating for a temp barrier instead of chrome?

Never crossed my mind. Do I understand correctly your saying that with only a polished aluminum intake your coolant went up 10-15 degrees? My first thought would be that the intake must dissipate a tremendous amount of heat on that rascal. Also one other thing I remember about the S/birds was a very highly tuned to the max performance engine. This, like an all out racing engine would generate a lot of heat and as you say dealing with it would necessitate every thing being "heat friendly." On the other hand our MM engines when stock are a long way from being close to the limit as far as power potential is concerned so once again I think that this chrome on a street motor causes negligible heat gain and performance loss.

One thing that would be neat would be to measure the heat in the intake air in the plenum before it goes into the head. I don't readily see how I can do that though.

Any suggestions?

[cyclone03]

IMHO

Wouldn't chrome work both ways as far as reflecting heat?

In a short cycle situation,ie drag racing,the intake would not pick up heat from the outside as quickly so the inlet charge could be cooler.
besides the EGR where is heat picked up INSIDE the intake?
I know the intake is bolted to the heads.

Is it the intake manifolds job to cool the engine? No.
Wouldn't you want to only allow the radiator to transfer excessive/waste heat to the outside air?

Seems holding heat in and transfering it to the coolent,not every outside surface of the engine would lower the underhood air temp and the inlet temp as well.