downwinddave

As I recall from my High School cal·o·rim·e·try flat black is best.

Does a shinny engne have a reduced capacity to transfer heat?

What kind of "finish" does the throtttle and dynamic chamber have?

What are the long term ramifications of removing the anodized finish?

Asks he with Five Star industrial strength metal polish in hand.

adamlewis

Most of the heat transfer is done by your coolant...These arent VW engines :p

If you want to polish your engine, go for it.

kdxer200

A polished engine WILL NOT cool as well. With the rough finish you have more surface area thanks to all the little peaks and valleys, where with a polished finish you dont have the surface area. You probal woulnt really notice it on the factory temp gauge if you polished your engne.

scathcart

Which would mean a lot if our engines are air cooled. But they're not.

You wouldn't notice a change on ANY guage.

BlackRx7

prolly like 5 maybe 6 degrees at the most, you have to think about how thick the manifolds are too....

adamlewis

Im glad someone else realizes this

BlackRx7

I wish they could be aircooled that would save a bunch of wieght no water pump, radiator, or all those thermo sensors, but the rotary produces way to much heat!

NZConvertible

Not true, many rotary engines have been air-cooled, just not Mazda's ones.

88IntegraLS

Um, heatsinks would be made out of metal and would need to be added to the engine . . . then you would need a more powerful fan because aircooling is not as efficient as liquid cooling, just look at the cooling inlets of an aircooled airplane vs. a liquid cooled one. Aircooled Cessnas have larger inlets than something like a Cirrus V kitplane, the latter of which has twice the horsepower per engine than the former (with twice as much cooling necessary). Ever notice how few VWs there are in Arizona? The 110 degree heat fries the engines!



Any of you NA guys ever thought of a composite intake manifold? It would not absorb engine bay heat like the aluminum, nor would crankcase heat travel up it via metal conduction . . . 'glass filled nylon maybe? It would be tricky getting it strong enough though.

turbojeff

iTrader: (30)

Plastic intake manifolds are commonplace nowdays. Just go look under the hood of a bunch of new cars. C5 vettes come to mind first. Strength isn't an issue, tooling cost is. You'd be looking at well over $100K to make the molds for the intake manifolds...

Aircooling SUCKS, the tolerances are bad because the engine has to run in a much wider heat range.

Jeff
Designs injection molded plastic parts for a living...

Digi7ech

iTrader: (1)

"Ever notice how few VWs there are in Arizona? The 110 degree heat fries the engines! "

Dude there are a sh*t load of vw's here. The heat doesn't fry the engine it fries the driver.

M5150

the C5 vette doesnt have a platic intake manifold, rather it has a plastic intake manifold cover, as for non metalic intake manifolds, the RE Amemiya GT300 car....or was it GT500.......whatever haha it uses a carbon fiber intake manifold

NZConvertible

Yes it does.

fastrotaries

what? The runners on the that pushrod are some plastic composite thingy. They're painted some flat silver finish, but it's plastic alright. However the camaro's are aluminum. Don't know about the 01-02 's though.

scathcart

Try maybe .5 or .6 degrees, if even that.

88IntegraLS

Yeally, wow didn't notice any in Mesa / Tempe when I lived there a few months ago. Glendale is another world from the East valley . . .

There are a sh*t load more VWs and Subarus here compared to Arizona dude!

88IntegraLS

Aaah, you design plastic injection parts for a living, eh? Engineering major? I am hoping to start engineering school at OSU next fall, we'll see . . .


I do know how much more time consuming it is to make molds for composite parts (ie. glass kitplane fuselages for example) compared to just making a foam plug and doing a wet-layup. Injection moulding would be a different thing entirely.

Let me know if there are any plastic injection type of jobs there, Corvallis' economy is feeling a little dead right now.

MrBob 86

All GM generation 3 V8s (LS1, LS6, LQ9, ect.) have nylon intake manifolds.

opelbits

iTrader: (5)

It was not so much the 'shinny' engine that had problems, but the 'chromed' engine. The chrome plating is a rather dense material that acts as a heat barrier. Kind of like the thermal coatings used today to control where the heat in a motor will go or not go. It was usually a problem on those chromed out hotrods and bikes/VW's in the 70's. Especially the bikes and VW's.
If you remove the anodized finish, the aluminum will corrode (little white-ish mineral deposits) just like the replacement waterpump on the car right now. Or look at the fan clutch. But, you could have them re-anodized/clear powder coated after polishing.