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Resistance

kcbugeye1275

Jedi Knight
Offline
I've driven the bugeye about 800 miles without the bonnet on it. Wonder how much more wind resistance there is in comparison with the bonnet. I read yrs ago the mga had about a 3 to 5 mph difference with the coup vs an open version at top speed.
 
I seem to recall a 1" diameter piece of tubing can have as much as 100 pounds of resistance at 100 MPH if it's over a foot long. Specific numbers escape me, this was as we were fabin' up control arms for a nearly-from-scratch F-A car...
but my memory ain't that good anymore.

I'll just say you likely have the aerodynamics of a billboard. /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
It has to do with the dimensionless coefficient of drag (Cw) and the frontal area. It's the Cw that changes here as the frontal area is the same. Sharp edges where the air must go "sideways" to the normal flow, and change to "with" the normal flow are the worst. For example compare a retangular box with a Cw about 0.8 and a VW bus with a Cw around 0.5. The difference is the rounded corners of the bus. All those air deflections cause drag. But the original headlights sticking up in the airflow also cause drag. I suppose it isn't a whole lot better, especially at low speeds. If you really want to reduce drag, go for the Speedwell bonnet.
 
You want the walker bonnet
walker3.jpg
 
Oh, lookin good indeed.
 
You know, I always thought about doing exactly that, but was afraid the lights would intrude into the wheels too far!!! That looks really cool though. Amazing how it modernizes the car! I also thought of leaving the "scallops" in front of the bugeyes for air induction scoops (kinda like a Ferrari Berlinetta)!
 
Along this vein...

Several years ago I was about to discard several old, banged-up Spridget front fenders.
As I looked at them, I thought: "What if....?" (always a dangerous thing for me)

Anyway, in a few hours I'd hacked together these "slantnose" fenders. I can't run them in our EMRA races or any of the vintage stuff, but maybe a hillclimb or something.
Actually, at some point, I'd like to make a nice set of these and put them on my street project. Headlights could go in the grill area. Maybe build them into a one-piece, flip-forward nose.

ss_sprite.jpg
 
I like that Nial, very "aggressive" looking! Just mount some of those new headlight units off of something new into the square openings and fair them in, that would look cool!!
/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]You want the walker bonnet[/QUOTE]

Yes. Yes I do.
 
bugimike said:
I also thought of leaving the "scallops" in front of the bugeyes for air induction scoops (kinda like a Ferrari Berlinetta)!

Like the Frobus Special?
 
Trevor Jessie said:
bugimike said:
I also thought of leaving the "scallops" in front of the bugeyes for air induction scoops (kinda like a Ferrari Berlinetta)!

Like the Frobus Special?

Never seen that! Have any pix??
 
It's got GILLS, too!!! /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif

Second cousin to a 300SL Gullwing!
 
Like that, only different! Sans bulges, just a flat hood and the faired in headlights in the fenders. The "gills are a nice touch though (are they for "venting" smelly feet?)! /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
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