black bonnets

[thebullettrain]

Does anyone remember how in the 1980's and early 1990's police Range Rovers had black bonnets?

You can find them here [url] www.pvec.co.uk/ [/url]

I've now seen another at [url] www.inlacal.com/X5/ [/url]

Does anyone know why this is?

[hoganscrogan]

because the glare from the sun on the big white bonnet was not very pleasant, don't ask me how I know this!

[thebullettrain]

How do you know that?

And how come it doesn't happen anymore?

[jc8542]

Lots of rally cars used to do it for the Safari rally.

www.phoenixc.or.jp/~mizutani/diary/rally_hokkaido/datsun240z.htm

Reduced the reflection but could you imagine how hot they got!!

[Balmoral Green]

When I was little my dad had a Capri MK1, 1600GT, metallic bronze with a matt black bonnet, cool, cool, cool.

[jimbro1000]

jc8542 said:

Lots of rally cars used to do it for the Safari rally. www.phoenixc.or.jp/~mizutani/diary/rally_hokkaido/datsun240z.htm Reduced the reflection but could you imagine how hot they got!!

Don't forget that they would have been better at radiating the heat as well as soaking it up. Still wouldn't want to put my hands on such a bonnet after a day's running though....

One other thought - how many of those panels are actually GRP/CF anyway in which case they need to be black to help transmit that heat...

[jc8542]

That Nissan (or similar to) and also Austin Land Crabs were rallied in the Safari Rally, Africa.

From experience, a black painted bonnet in an equitorial sun reaches approx. 90-100°C

[cortinaman]

we used to have egg and bacon sarnies that were cooked on the bonnet of my dads fx4r during summer when my brother and i were kids.......maybe it saved the trafpol going to a local greasy spoon for their dinner too?

[dinkel]

Lots of tunies have black bonnets . . .

[shadowninja]

Thats cos its unpainted carbon fibre bonnets... which is now becoming trendy in the max power world. i saw a saxo with a painted matblack one the other day

[LuS1fer]

It used to be a rally-tastic touch to any vehicle but probably began in the US in the muscle car era and was designed to radiate heat away from the engines (black radiates heat faster than light colours).

This was my favourite rally car - the 1971 East African Safari 240Z

[wedg1e]

Surely, under a blazng sun, matt black also ABSORBS heat the best...?

Ian

[dinkel]

I thinks it is a looks thing . . .

[Fatboy]

wedg1e said:

Surely, under a blazng sun, matt black also ABSORBS heat the best...? Ian

Under the bonnet's going to be a damn sight hotter the ambient temp, even with the sun I'd have thought?

[CanAm]

First such example I can remember were the Ford GTs at LeMans in 1964, with dark blue bonnets. Obviously for looks/glare reduction, the engines being amidships. First used on US fighters in WWII as an anti-glare panel in olive-drab or black when the finish was natural metal all over.

[Dave^]

[quote=LuS1fer]
(black radiates heat faster than light colours).
quote]


not true - you paint your radiators in your house black - and see who's cold.....

[rob.e]

Dave said:

LuS1fer said: (black radiates heat faster than light colours). not true - you paint your radiators in your house black - and see who's cold.....

Nope, LuS1fer is right. Black radiates better than white. The only reason the radiators in your house are white is for the aesthetics (white looks nicer).

>> Edited by rob.e on Friday 18th June 17:08

[Dave^]

do you have black radiators then?

[Fatboy]

[quote=Dave^]do you have black radiators then?[/quote]
That's just aesthetics. I'm pretty positive black radiates heat better than white, unless I've totally forgotten all my A-level physics (Black body radiation anyone?)

[Dave^]

dark colours absorb heat - light colour reflect heat....

i'm guessing - IF they wanted to use bonnets to dissipate heat, they would of been black inside, and white outside......

White isn't used on heating radiators because of the asthetics....
somewhere in europe, [think it's germany - not sure tho]public buildings have to have thier heating systems flow pipe in the top of the radiators and the return at the bottom,[which looks crap] because it's [insert supidly small number]% more efficiant.....
if it was the case that darker colours radiated more heat - i'm guessing that their radiators would all be matt black......

btw - i'm a heating engineer....

i dunno if the same principles would apply.....