How hot does the plenum get? (in Celcius, 'very hot' is not the answer i'm looking for :P :D )

 

I'm toying with the idea of getting my plenum powder coated while the lumps out... anyone done this?

 

Any drawbacks? any pics? Will it flake?

People use caliper paint to paint it, so I'd say "cooler than your brakes get" ;)

People use caliper paint to paint it, so I'd say "cooler than your brakes get" ;)

 

I'd have to concur with my learned friend.

 

;)

 

Matty.

Well brake calipers get pretty warm, but much of the heat stays in the discs and pads so they might not be as hot as the plenum. I have an infrared thermometer and so I'll test it sometime, but I doubt whether the plenum gets much above 100 dec C.

 

In fact I may even have measured it before, try a search ....

Did a search :D couldnt find it

I measured it a few times and the hottest I have ever seen was 85 Celcius (after a good drive on the nurburgerring :D ).

But...I did some things to improve airflow under the bonnet, so on a stock car it might even get hotter.

Also there are some parts of the plenum that get quite a bit hotter then the rest.

 

-Eric

Will powder coating a plenum make it get hotter? I thought it would.

 

I know in theory polishing it will make it hotter, as there is less surface area for it to cool down.

Don't think it's the surface area, more likely that matt surfaces radiate heat better than polished ones (if I remember my O level physics)

Did a search :D couldnt find it

 

Sometimes search can be tricky, but I did find this :-

http://www.300zx.co.uk/forums/showthread.php?t=8605&highlight=infared

Don't think it's the surface area, more likely that matt surfaces radiate heat better than polished ones (if I remember my O level physics)

 

 

The more it radiates heat the more heat it loses and the quicker it will cool down..

 

Radiators have fins on it to increase the surface area. The larger the surface area the more it cools or the quicker it cools.

 

A bumpy surface has a larger surface area than a perfectly flat one. Even though the boggles/lumps on the plenum are not that big, there are thousands of them, which all add up to to increase the area by a significent amount.

 

I wonder if it is significant enough to affect the cooling.

 

Stuart

The question to ask is WHAT heats the plenum up? If its the surrounding air then a polished one will run a lot cooler ;) The fact that the surrounding air is warm also would suggest that its cooled by radiating heat rather than conucting to the air...

The question to ask is WHAT heats the plenum up? If its the surrounding air then a polished one will run a lot cooler ;) The fact that the surrounding air is warm also would suggest that its cooled by radiating heat rather than conucting to the air...

 

It's also bolted to a whopping great aluminium heatsink... ie the rest of the engine. :D

Poweder coated plenum - Colin Dick - Dick300 had this done a couple or more years back and it looks very good.

 

..or you could get it polished while its off

It will be cooler if you, do the throttle body bypass!