car wax

[Bicycle Bob]

When laminar-flow sections are tested in wind tunnels, they are very smooth but not necessarily shiny. You can look up the "standard roughness" used to trip the flow into turbulence - I think it is .003" Probably the best thing about waxing is that it removes bugs and slows the re-accumulation.

[dremd]

Honda did release an article last month about how if "...Large vehicle owners wash and wax and keep their vehicles clean they can see an increase of 10%mpg hwy" Of course it said results may vary.

Anybody have this article? I'd love to read it.

[Ford Man]

Originally Posted by meemooer

but the "slickness" to the paint is so microscopic. the small voids that the polish/wax fills can only be seen under a microscope.
Honda did release an article last month about how if "...Large vehicle owners wash and wax and keep their vehicles clean they can see an increase of 10%mpg hwy" Of course it said results may vary. Maybe they should just come out with "aero" packages like Dodge did w/the Daytona Superbird.

Go find a car that hasn't been waxed in 5 years and one that has just been waxed that day and try to slide a cloth across the paint of both and see what the results are. The cloth on the one that hasn't been waxed probably won't slide at all and the cloth will probably slide onto the ground on the one that has just been waxed. Rain X does the same thing to the glass that wax does to the paint.

[BlackDeuceCoupe]

Originally Posted by Ford Man

Go find a car that hasn't been waxed in 5 years and one that has just been waxed that day and try to slide a cloth across the paint of both and see what the results are. The cloth on the one that hasn't been waxed probably won't slide at all and the cloth will probably slide onto the ground on the one that has just been waxed. Rain X does the same thing to the glass that wax does to the paint.

True and true!

I bought my first Honda CiViC brand new, off the showroom floor. The dealer offered a *free* lifetime guarantee on the factory paint job, if you let them reapply the Poly-Razzmatazz Coating every 6 months (which they reapplied for *free* BTW).

Dude, that stuff was sooo slick, I couldn't keep the car cover from blowing off my ride for weeks afterwards!

And, Rain-X is miraculous too! Not only does it repel raindrops, but snow bounces off your windshield when you're driving - looks like HyperDrive in Star Wars!

[Bror Jace]

Guys, there was a thread here not long ago where an aeronautical engineer weighed in. Basically, there are two forms of drag (I forget the terminology) and the drag associated with smooth, slippery surfaces doesn't come into play until you are travelling hundreds of miles per hour (aircraft speeds).

I love to wax my car to prevent the paint from drying out and or losing its color (and I love Rain-X, too ... been using it since 1985) but there is no efficiency issue with the condition of the surfaces of our cars (which is why Basjoos' FrankenCivic works so well despite it's rough fit and finish.

[Bror Jace]

Here is one thread that talks about drag caused by the condition of the surface ... but it's not the one I was thinking of.

mods-data-%change Cd or drag(installment#3 surface drag)

[BlackDeuceCoupe]

Originally Posted by Bror Jace

Guys, there was a thread here not long ago where an aeronautical engineer weighed in. Basically, there are two forms of drag (I forget the terminology) and the drag associated with smooth, slippery surfaces doesn't come into play until you are travelling hundreds of miles per hour (aircraft speeds).

Originally Posted by Bror Jace

Here is one thread that talks about drag caused by the condition of the surface ... but it's not the one I was thinking of.

Good point!

If a shiny, clean car DOES get better FE, it would only be the case at highway speeds!

A little dust on the surface would not have any measurable effect on the MPG, but if there are sizable clumps of dirt on your car that significantly alters the air flow along its surface, then it WOULD reduce your gas mileage.

Wax, et al, and Rain-X can only improve matters...

[Bror Jace]

True BDC, it can't hurt.

But the poster in the thread from several weeks ago was pretty clear that even most race cars would not benefit from a waxed surface versus one that was rough and pitted.

I asked him if he could tell me the speed at which drag from the condition of the exposed surfaces would come into play and he said it wasn't quite that simple ... actually depended on a number of factors. I came away thinking of speeds in excess of 200mph.

I looked for the thread for about 20 minutes ... but I just can't think of his name nor any key terms used in the thread.