My new hopefully more aero Metro front bumper

[MetroMPG]

Originally Posted by Coyote X

Now if I was drilling holes in the bumper of my Volt you guys could rightly call me goofy

I was just going to ask... whose Volt is that!

And for clarification, if you started modding it, it would quickly go on the front page.

I knew your PHEV Metro XFi convertible project was a gateway drug...

[Patrick]

Originally Posted by Coyote X

I am thinking of folding the bottom half back inward to get the stagnation point a bit higher. Right now it has a huge amount of down force on the front end of the car and I am sure that is not helping the mileage. I am thinking that where I put that brace, as seen by the rivets in the middle, is probably a good place to heat and bend it back. I can then use a small lip under the radiator to direct air through it and solve the fan cycling all the time while driving. On that chart it is hard to find an exact number where to make the fold but I figure anywhere is going to be better than all the way at the bottom.

Here's a drawing of the "optimum nose":

Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - aerohead's Album: Book illustrations - Picture

[California98Civic]

Originally Posted by Patrick

Here's a drawing of the "optimum nose":

Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - aerohead's Album: Book illustrations - Picture

[aerohead]

Here is a link to an image of early use of the low stagnation point 'optimum' nose,by Geoffrey de Havilland's Airco D.H.2,of 1915.
http://houseofqueeg.files.wordpress....h2-04-1200.jpg

[freebeard]

That dotted line looks a lot like my Superbeetle.

[Frank Lee]

No, it looks like a lady that shall remain un-named.

And the next one up is a dead ringer for a Ghia!

[Frank Lee]

Parachute effect!

[Xist]

Originally Posted by aerohead

Here is a link to an image of early use of the low stagnation point 'optimum' nose,by Geoffrey de Havilland's Airco D.H.2,of 1915.
http://houseofqueeg.files.wordpress....h2-04-1200.jpg

This is all that I know how to do.

[Coyote X]

I tried heating and folding under the bottom couple of inches of the bumper. It worked ok but it was really lumpy since I was just doing it by hand. I took it for a quick spin and the car seemed more neutral but maybe a slight bit more downforce than stock on the front end. That is probably about right I figure so I put it back in the garage to try and make it look less ugly.



The easiest thing to do since the curve was basically ok was just cut the bottom off and put a strip across the bottom. I used a bit of heat to form up the joint a bit to make it look nicer.



I also used a strip of bumper material to make an air deflector under the radiator.



Now after a quick drive the car seems to drive about right and the fan did not come on at all so it should be getting enough airflow. I will get a picture of it on the ground tomorrow in the daylight. But I did notice when it was parked beside the volt that I have more or less copied the exact profile of the volt. The bumper and hatch angles are almost identical.

[serialk11r]

Oh dear that underbody is even more dreadful than on my car. Bellypan it!