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Mythbusters on ffcars! toilet paper test - do hood scoops really work?

12K views 43 replies 35 participants last post by  Horizon200  
#1 · (Edited)
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step 1: tape Charmin (the softest, 2-ply ass-wipe you can buy) to $6,700 Jeff Miller paint job.





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step 2: drive pretty fast. note asswipe stays inside hood scoop.





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step 3: note shredded edges that prove existence of 80mph wind in hood scoop!


step 4: re-use toilet paper. (EFI only, too many fumes from Carburated engines - ouch!)



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#3 ·
"note asswipe stays inside hoodscoop" are you sure that is where the real asswipe was?! LOL:devil2:
 
#8 ·
I was thinking the same thing...behind the wheel?

Great stuff Eddie!
 
#9 ·
Not only did you answer a tech question that has been discussed here recently but you also gave me a laugh..great job Eddie!
 
#13 ·
I think we need a video of this test... :lol:
 
#15 ·
Thanks for skipping the Step 4 picture...:blink:
 
#16 ·
Simplicity at its best....that was great!
 
#17 ·
the T.P. did blow out once. it was at a stoplight, and it was a little windy. the wind from under the car + wind from the fan must have pushed it out.

it tucked itself back inside once i started moving.

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#19 ·
Hood scoops and TP

You guys are nuts, especially you Eddie. Keep it up.
 
#21 ·
Great Post Eddie,

How about another... At what speed do you not get wet in the rain without a top.

We may have to wait a while here in Cal.
 
#22 ·
Wow. That is UNBELIEVABLE!!!!
A paint job that nice for under 7K??!??! He does do some amazing work.

So, I guess all we need to do now is to find out what the paper will do on Kouros's wicked cool hood vents.

That was very good, NGE. Thanks.
 
#23 ·
Way to go Eddie!! That question's put to rest.

Prior to windtunnels we used to be much more sophisticated than that on our Learjets. We used yarn! :D

btw, I saw a similar Mythbusters that should have been busted.
Their result was bo oooooh gus!

They did a test of whether an SUV running A/C, or one without A/C but the windows rolled down, would run out of gas first.

The "non A/C" won, but they ran the test below 45 mph because they were afraid of losing control on the circle track they were going around.

Aerodynamics doesn't hit hard until you're above 50! Talk about A$$wipes.

d



 
#24 ·
test data:

1. side-street driving, 0-30mph, 3 minutes.
2. highway driving, 75mph, 2 minutes
3. side-street driving, 40mph 5 minutes.

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#27 · (Edited)
Not so fast....

I wouldn't call it busted just yet...

I think there are other variables to take into consideration - not the least of which is speed.

In my Challenge Car, I forgot to lock my hood latches at the rear of the hood.

The one on the left had vibrated loose and at ~120 mph the left side latch let go and that side of the hood popped up a good 8" while the right side remained latched shut.

Now - do you suppose it was the massive amounts of air coming in trough the iddy-biddy slit of a hood scoop or do you suppose that it was because of the frontal area of the car that includes a mouth that would make your mother in-law look like a guppy?

I'm leaning away from the air-scoop....

Other factors;

> No large windshield - only the Challenge Car racing shield
> Challenge legal air-dam was in place
> Increased spring rate on all 4 corners ensured that the ride height remains with front lower than rear by 3/8"
> No asswipe in or on the car..

--edit--

This happened while in race trim while qualifying at Brainerd International Raceway.