I don't spend a lot of time on the underside of things... But that's interesting. I suspect if it were true for air, planes would have shark-skin on themjohn1701a said:And have you noticed how the underside of boats are not smooth anymore?
Because air resistance goes up the square of speed, this is much more significant for planes than cars. My airline pilot father mentioned back in the 60's that a dirty DC-8 used about $2,000 more fuel than an clean DC-8 in a trans-atlantic flight. I doubt any car would see that big of a hit.melgish said:Well, I remember a job interview at a Rainbow Polish outlet back 'round 1989. The guy mentioned a pilot that used their polish on his plane and claimed better fuel economy.
So I figure there must be some 'best mix' out there, and if I'm going to wax the car anyway... I might just as well pick a wax that will pay for itself through MPG
Good question. I had never really paid much attention. I'll have to do some research now.BIF said:It's my understanding that runflat tires have more mass, because of the stiffer sidewall. So wouldn't that extra rotating mass be a direct drag on engine and electric motor performance?
And if this is true, would the rotational drag be less or more when compared to the lower-mass tires plus the weight of a lightweight "donut" spare tire in the trunk?
A question beyond my own ability to answer.
In the 60's fuel was $0.20 a gallon. So $2000 = lots of gallons. If all other factors are equal, than any improvement would be better than none at all.jfschultz said:My airline pilot father mentioned back in the 60's that a dirty DC-8 used about $2,000 more fuel than an clean DC-8 in a trans-atlantic flight. I doubt any car would see that big of a hit.
hehe.. No wax will make enough of a difference to 'pay for itself'. Choose based on how nice it makes your car look, how infrequently you have to reapply, how much it costs, or other esoteric things. Don't even worry about its effect on mileage. (Waxing in general will make a SLIGHT improvement, but again, not enough to pay for itself, and no wax is *SO* much better that it pays for it's price increase over normal wax. Cheaper wax will provide better 'drag reduction for the money' simply because it's cheaper.) Water has significantly more resistance than air, that is why wax makes more of a difference in water. (Boats, surfboards, etc.)melgish said:In the 60's fuel was $0.20 a gallon. So $2000 = lots of gallons. If all other factors are equal, than any improvement would be better than none at all.jfschultz said:My airline pilot father mentioned back in the 60's that a dirty DC-8 used about $2,000 more fuel than an clean DC-8 in a trans-atlantic flight. I doubt any car would see that big of a hit.
So I'm back to..if I'm going to wax anyway...which wax is best
and ehurtly: I'll also go back on my diet to reduce the heavy objects in the car![]()
LOL! I think I'll just live with what I've got. :lol:patrickg said:Golf balls have little dimples and hence less drag than a similar smooth ball. Maybe you should take a small ball pein hammer and or a small punch or awl and make little dents all over your car.
And contribute to beach erosion.... never! ;-)patrickg said:Alternatively take it to the beach and spray it with spray cans of clear and then throw sand all over it. Remember it is the mileage that counts, not looks.Pat
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Which is why I like Oregon. Every inch of coastline is public property. Yes, there are hotels on the beach, but they don't own the beach itself, and can't do anything to the beach without government permission. (Like installing 'sand trap thingies'.)patrickg said:Melgish, Ironically it is often developer money spent to build the "STICK OUT IN THE OCEAN TO TRAP SAND THINGIES" to preserve their beach that holds back the sand from the next stretch of beach down current.