Heresy! Smooth Wheel Covers- Myth Busted!!!

[gumby79]

. Show me a land speed record holder where cutting .002 CD is a huge gain that can cost $10,000's in r&d that is running a Tesla/ insight style wheel.
Or is the .002Cd gains from this style of wheels so insignificant that is not worth the $ investment to a team that has spent millions of dollars to to get .002 to go faster? Maby I'll be the one.
The world's fastest Honda Insight didn't even run Honda Insight Wheels


Got a BMW shirt that says" Good is the Enemy of Perfection. " let's face it most folks on here don't drive a Benz Beamer or Tesla, and good is better than not trying.

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As mentioned the wheel that is perfect for position A is sub satisfactory for position B. Did Tesla test different combinations of wheels in different positions? if not then by standard it is not a valid test and must be thrown out with the bathwater and baby, as there might me more left on the table.


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When teknomage2012 did his eggbeater Factory Nissan Leaf alloy wheel to 95% full disk (pizza pan left a 3/8-1/2" air gap around the circumference) circa 2014. It showed a l significant increase in kilowatts per mile .3-.5kw/mi. My theory is the wheel with behaving like a rotary air pump. Would be great for a performance application needing additional brake cooling flow but for a hypermiling Nissan Leaf they were thrown in the rubbish bin.

Dream Big Chisel Down To Reality

[JulianEdgar]

I really don't understand why people have apparently such invested emotional capital in this.

I couldn't care less whether full wheel discs or slightly open wheels are best for low drag.

I am simply reporting what the current technical evidence shows for road cars.
And that is that full wheel coverage is not always best for low drag.

[Shrug] Personally accept that or not as you wish, but don't tell others BS.

[freebeard]

I couldn't care less whether full wheel discs or slightly open wheels are best for low drag.

Here's my next set. What color should I powdercoat them?

[JulianEdgar]

Originally Posted by freebeard

Here's my next set. What color should I powdercoat them?

On the Beetle? Black? (But I always kind of dislike black wheels on cars, with very few exceptions.) So, boring old silver.

[gumby79]

It's that the number one rule is testing is required, ABA is preferred, backed up with long turn tank to tank results .

Everything is a suggestion and requires testing to determine if it fits in your use case, as you and I have come to the conclusion of on YouTube, not every rule Works in every use case .

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This will be a good throttle stop test for anyone who happens to have an Insight with Factory wheels and a roll of duct tape to add to the knowledge.

Would higher % throttle be better in this instance?

Accuracy check: The smaller the Delta Cd the higher the speed/throttle % is needed to make it show above the noise.

Why am I so passionate about aerodynamics and learning in general because they said it's a waste of time just drive the thing, and then they are astounded at the results. Driving is my therapy, the more efficiently I can make my tool/truck the more therapy I get, it's a bang for the buck kind of thing. Yes I could trade my multi-tool in for a single-use tool commuter car but that kind of ties my hands on doing things that make me, me.

[California98Civic]

Absolutely gumby79.

[easythereturbo]

So much win here on page7. Good enough > perfection. Emotional investment.. and black wheels so so trendy. But to each.

I feel the same way about large wheels, so trendy. But what sells on the showroom floor matters to car makers more than anything. Understandably. So wide glossy black 22x10's sticking right up to the fender edge it is. Aero be damned.

Here is one for anybody who thinks you need huge wheels to have a sporting time in a car..

https://www.youtube.com/watch?v=HPh90yNX-mY

IMO the FRS dev team got it right when they spec'd skinny LRR tires as standard on that one. And the fun to fuel cost ratio on that vehicle happens to be very high.

[aerohead]

Originally Posted by TimRogers

The only downside of this testing data is that Lockheed Marietta's wind tunnel is not a rolling road type. Without the wheels turning, one of the most important factors of how the turning wheel interacts with the windstream is not represented in the test.

Speaking of windstream, the Windstream wind tunnel in Concord, NC is a modern, full scale rolling road wind tunnel.

The only way to factually determine a 'downside' is, to re-test the Pontiac at Windstream,with and without rotation,and publish the difference.Otherwise,it is scientifically impossible to know,one way or another,and pure speculation on your part.

[aerohead]

Originally Posted by JulianEdgar

It's actually even worse than that because that car wouldn't have had an underfloor design anything like most of today's cars. (Tesla found the undercar flow influenced the best design of wheel.)

Speculation.

[aerohead]

Originally Posted by JulianEdgar

I really don't understand why people have apparently such invested emotional capital in this.

I couldn't care less whether full wheel discs or slightly open wheels are best for low drag.

I am simply reporting what the current technical evidence shows for road cars.
And that is that full wheel coverage is not always best for low drag.

[Shrug] Personally accept that or not as you wish, but don't tell others BS.

When you refer to what was, in it's day,state of the art data,acquired in world class facilities,and then characterize members who share it as broadcasters of BS,at least,in my experience,it evokes a need to offer a counterfactual counterpoint,or else,you come off,exactly the same way.Not once,have you offered a single example where the data presented has been found to represent a quantitative excursion beyond the standard deviation,experienced between one tunnel and another. You've proved nothing.Bring us the empirical evidence unless you want the accuser to suffer the same judgement as the accused.