Frontal impact drag reduction

[mcrews]

Originally Posted by razor02097

Hammerhead Eagle i-Thrust

In a wind tunnel, the car was so aerodynamically poor that it slid across the test area, and we are told that it crashed into the fans at one end.

[MetroMPG]

Originally Posted by GBld

(with permission already from the administrator here at ecomodder)

This is true - I received a polite email from the original poster asking if he could link to a crowdfunding page for a new aero product.

I agreed, as long as details of the product be shared in the forum.

(Details of the product weren't shared in the email, or else I would have also advised to prepare for healthy skepticism.)

Carry on.

[GBld]

Originally Posted by Flakbadger

I'm submitting my petition for this to be moved to the corral, unless some tangible testing is done sometime soon (which I doubt).

1/17/2013, 3' aluminum 1 1/4" edges, duck tape on the surface (pic 2), 4" arms, 70mph on cruise control, 14 mile test runs (7 North, 7 South).

A - 37.13mpg, light traffic Northbound, light-med South
B - 38.94mpg, light-med traffic North, med South
B - 38.47mpg, light-med North, light South
B - 39.04mpg, light North, light South (lowered arms, increased angle)
A - 36.70mpg, light North, heavy South

These are with me reading instant mpg at mile markers (overpasses, one at each mile on this flat stretch of hwy) and averaging the whole.
I am finding the variables: cars passing, trucks passing, drafts, breaking and getting back to speed...

No more replys for a while, got to shower off the pee and get ready for work.

[mcrews]

Common sense would suggest that you could aba test it in about 5 minutes.
What 'data' do you have?
Surely you would have a before and after.....
search ABA testing so you understand what we are talking about.

Here's the bottom line.
Posters have suggested an idea, built it, tested it and found it didnt work......guess what?
WE LOVE THOSE GUYS!!!!
Other posters throw stuff up and never aba test (however, may claim many other tests)....we throw those guys under the bus.

This has been said before....this is a VERY great group. VERY smart. and very good at communicating on a 'forum' level.
But we do have a minimum standard for a untested idea. aba test it!

Good Luck!

[MetroMPG]

Originally Posted by GBld

These are with me reading instant mpg at mile markers (overpasses, one at each mile on this flat stretch of hwy) and averaging the whole.

You need a fuel economy computer that does the averaging for you. Something that you reset once at the beginning of your course, then read the result at the end.

cars passing, trucks passing, drafts, breaking and getting back to speed...

Doesn't sound like an appropriate environment to try testing.

[mcrews]

please see the first link in my signature for a discussion of the ScangaugeII

[ChazInMT]

OK, a 6mpg increase could be due to almost anything. My tank mpg's on my Honda Civic are between 27 and 42 MPG. Did I do anything to get a 15mpg increase? No, the climate does, and my driving habits. If I put a gum wrapper on my side rearview mirrors, and the temp goes from 10°F before and I'm going into a 30mph headwind while maintaining 70mph on the highway, to 65°F the next day with a 15 mph tailwind going 55mph down state highways with hills. Do I post a 15mpg gain from the gumwrappers stuck to my mirrors? Heck no, not in here, your credibility goes to crap.



We know better. We know a 6mpg gain on a 25mpg car means a 24% improvement in mileage, which means a 48% improvement in aerodynamic efficiency. We know that most modern cars have fairly optimal front ends for aerodynamics, and that 70% of the aero gains that are possible come from improving the back portion of the vehicle.

So when we do the math, and see that the front 30% improvement potential, from a car already optimized fairly well, leading to a maybe 6% left on the table for improvement, and only half of this means an mpg increase, we see the 3% fuel efficiency potential being somehow 24%.

That's when the flag is thrown.

[Flakbadger]

Originally Posted by GBld

Yes I am new to ecomodder, and even to forum writing. Gee there is some passion here. Didn't know you could get urinated on!

We just believe in tangible data, that's all. Maybe we're a bit harsh, but if you spend some time in the Unicorn Corral, you'll see why. We have seen dozens of "miracle products" or "miracle innovations" that promise to add ludicrous amounts of MPG's, from hydrogen generators and gas-system magnets, to air turbulence generators in the intake and additives of all types---none of them with empirical testing, all with overinflated claims of efficacy.

Maybe that explains why we all started beating you with a stick.

[ChazInMT]

Originally Posted by Flakbadger

We just believe in tangible data, that's all. Maybe we're a bit harsh, but if you spend some time in the Unicorn Corral, you'll see why. We have seen dozens of "miracle products" or "miracle innovations" that promise to add ludicrous amounts of MPG's, from hydrogen generators and gas-system magnets, to air turbulence generators in the intake and additives of all types---none of them with empirical testing, all with overinflated claims of efficacy.

Maybe that explains why we all started beating you with a stick.

Sorry, I meant to say this before my last post.....guess I forgot.

[Tesla]

It's kind of like a "nudge bar" or "license plate light bar",
The only way I could see it having any effect is to reduce the size of the pressure infront of the grille by tripping the air into turbulant flow.
I do seriously doubt it has any effect, but does anyone have any data for a similar concept or is everyone just going on accepted theory.
I do need to go check out the unicorns though, they're always cute.