New Member 07 Civic

[DifferentPointofView]

I get that all the time :-) My fuel gauge begins to move at 150 miles I call all of my friends every time I buy fuel now as well, they all tell me that they "Hate Me", "you Suck" or whatever (jealous); It is actually the highlight of my month (3.5~4 weeks to a tank).

lol. I just laughed when I thought about calling friends when you buy fuel.

Keen, looks nice. Nice photoshop skills :Thumbup: Your not worried about resale-value diminishing? You could always make your own trunk lid or go to a junk yard and get one from a wrecked civic to chop up, so that if you ever sell your car in the distant future, you have the original trunk lid to put back on there.

[SVOboy]

That definitely looks like an interesting design, do you think you'd be able to pull it off?

[Daox]

I think the angle of the rear trunk is too agressive and you'll have flow seperation at higher speeds. Also the sharper edges (where it steps) create vortices and can increase drag.

[DifferentPointofView]

^ true for the edges on the surface of the trunk, but at the tip of the trunk when the air finally separates on the car should be sharp edges like in his pic for clean separation from the car.

Also, like he said, the trunk angle might be too steep. you might be able to get it to end at the license plate the same way, however, if you start at the windshield angle and gradually decrease at a rate of 13 degrees. It'd be better than having a straight angle from the windshield.

[Keen]

Hi,

Thanks for the replies. I am planning on getting a trunk lid from a wreck. I wouldn't want to kill my resale value too much. I understand that I can't go too steep with the angle, as I might get seperation of the air stream. So I am planning on continuing the cuve of the rear windshield. My drawing makes it look much more aggressive than It actualy would be. I am also thinking that If I am getting a new trunk I might delete the rear tail lights that are mounted on the trunk lid. This would allow me to Have the entire trunk angled down. There are still a lot of details to work out. My main question is. Do you guys think this would work? Would it reduce the area of low pressure in the back? I'm pretty sure that the fuel savings won't offset the cost of time and materials needed to complete this project, but that really isn't my main concen. Mostly I want to do it to see if I can and if it works.

PS Anyone know of any salvage yards in the NYC metro area that I should be checking out?

[cfg83]

Keen -

Welcome to EM! The wrecker idea is good. Isn't the top of the tail-light closer to "following the rake" of the rear window? Here is a picture of what I mean :



CarloSW2

[Keen]

Hi,

Thanks for the input. The feedback is really helping me refine my ideas. So I just went out to my car. Poped the trunk, and taped a 3 foot aluminum ruler to my back windshield. The ruler naturally followed the curve of the window and continued that curve down into the trunk space. I marked where the ruler intersected the back surface of my car. It turns out that I did make my drawings too aggressive. With this new data I updated my photoshoped civic

Take a look and let me know what you think

Thanks for your help

[DifferentPointofView]

My question is, does the air still stick around when it gets to the trunk? or does it separate before hand? In otherwords, what is the angle of the rear window? isn't something like 13 degrees the ideal slope? or am I wrong?

[Keen]

The slope of the rear windshield is 22 degrees. The angle between the trailing edge of the roof, and the trailing edge of the trunk is 16 degrees. This might suggest that a small well designed spoiler might be better, or raising the surface of the trunk lid.