Aero template request

[2000neon]

That makes sense,I will look into that and try to figure out a good way to attach it and gibe it a try! After tufting to see what Im working with I really want to try a decklid extension.

I guess the idea of the base plate would be to "trap" a vortex to force the air to follow the template? In the theory it seems reasonable, but of course air is unpredictable. I'm sure that matching the height in the centre would be easy, determining how much to curve it down on the edges might have to be some trial and error.

[Frank Lee]

Originally Posted by Sven7

Your rear window is pretty darn close to template. You might consider tuft testing it first to see what's actually happening.

What pic are you looking at?

[JethroBodine]

My pic was a grab off the web, Svens is true to scale. I looked for a drawing but couldn't find one quickly, hence the out of perspective rendering.

I'm with Frank. I don't think you will get attached flow as the rear roofline deviates from template fairly early.

[Sporty Modder]

Originally Posted by Sven7

Definitely. If you're doing coast down testing I wonder if you'd be up for a little experiment. I don't own a sedan so I can't do it

Search the forum for "coventry papers" and read about the "base plates". I was wondering if one could make something like that that goes vertically up from the edge of the trunk, like a Bonneville spoiler that goes up (instead of out) to meet the template. Does that make sense? The advantage would be if it were made out of plexi it would barely be visible.

I just thought if you're doing it maybe you'd be down. A suggestion

I belive what you are describing is considered a gurney flap named after Dan Gurney in the 60's who used it on a Le mans racer finding minimal drag with huge downforce. Correct me if I am wrong.

[ChazInMT]

Here's my 2¢.

You shred the air at the top of your rear window.

If you really want to improve the shape, you must follow the template with something solid, a roof spoiler or a rear deck lid extension won't do much.

The air needs to "ride down" on something in order to return its energy back to the car, by the time it hits the extension it is too late, if you cut off flow with a roof spoiler, you really aren't improving on what you already have. The current shape is not terrible, it just isn't optimal. You have to add a "Kamm" extension to optimize.

[ChazInMT]

Sorry to do this Sven, but I think you need to look closer at your template, it appears to be out of proportion with what the standard is.

Here is a small pic.



and a link to a more detailed one.

Big Sven 2 Templates Compared

I have been very meticulous in maintaining this exactly. On several occasions I have slipped up and forgotten to maintain the aspect ratio thereby ending up with an out of proportion image.

You can see my template on top of Phils, I have verified again before creating this image, that Phils Image is the 1.78 aft ratio. My analysis of your template is about 1.5 aft ratio. The fronts are really not too important as we know.

Charlies Template on Phils Drawing

[kach22i]

The one I've been using is a little different, but closer to Chaz's.

Automobile 2 - Odds and Ends pictures by kach22i - Photobucket

[botsapper]

Some ideas from an older thread. http://ecomodder.com/forum/showthrea...tml#post217527

[Sven7]

I'm using this one. If it's wrong let me know and I'll delete it from my computer. Maybe we should sticky the Template Part C thread.



Don't know what a Gurney flap is. Basically a spoiler?

I'm not trying to say the base plate thing would be the final product, or that it should be used. I was hoping for a little data on it to see if it would even help. It was supposed to be a research project.

Of course a Kammback/boat tail will be your best bet for drag reduction. As long as we're testing the car we might as well test alternatives based on Coventry University data to see if there are other options for those pressed for time or money.

[Sporty Modder]

Gurney flap ... Think nascar rear spoiler