Project: making a permanent Metro Kammback extension

[MetroMPG]

That work thing is getting in the way today - no progress, no updates on the Kammback. Tomorrow I'll be back at it.

I've never noticed the trip strips on the Beemer tail lights. I'll have to keep an eye open for that. I looked for a pic, and only found this one of the 6 series (dial-up users beware), which shows what certainly look like aero treatment on the side of the rear lenses that would promote flow separation:

http://www.zastavki.com/pictures/160...__000192_2.jpg

protoge2003: I'll be mounting it with a combination of brackets and screws (or bolts). It would be simpler to just build it directly onto the hatch, but I seem to have a habit of doing things the hard way.

[lunarhighway]

toyota prius Cd 0.26

opel Insignia Cd 0.27

seems like a slight upward angle at the back is something to look into...

[MetroMPG]

I don't know for sure, but I'd guess those upward kicks are likely there to reduce rear lift, or to compensate for a less than optimal backlight angle (too steep, as is my guess on the Opel). The addition of a spoiler as we know changes the "effective" rear angle.

Rear lift isn't an issue for me because I don't drive anywhere near fast enough for it to be a problem.

[Whoops]

I saw a Toyota minivan with one of those top carrier soft bags. They used the flat hooks and nylon straps to strap it to the door frame. It had 4 straps attached to the top of the back door and one strap to each side.

I think your shape and glass work look great.

Down the road, maybe you can put a sort of skylight piece of clear plexiglass or something, if looking out the rear view mirror becomes enough of an issue to worry about.

[MetroMPG]

Update-o-rama...

I sturdified the structure by mostly enclosing the back end with more cardboard & tape and carefully peeled it off the car tonight. The "release agent" (tin foil) worked quite nicely.



All trussed up with cardboard to hold the shape for pulling it off the car & glassing in a lip & underneath







Showing the "release agent" - tin foil.

Spent time trimming the raw edges, added a glass & cardboard 90 degree lip to the trailing edge and worked on glassing the underside (until I ran out of glass cloth & applicator sponge brushes.

I was surprised to read today that Craig Vetter's latest motorcycle streamlining project is not going to be fiberglass construction. He's going with bulkheads/skeleton and a plastic skin. Composite construction is too expensive and difficult to ship is his reason.

I figure the total cost of the Kammback will come in around $100. Most of that will be resin & glass cloth. (I also didn't try very hard to find a cheap source for it - just picked it up at Canadian Tire.)

[MetroMPG]

The car is apparently looking weird enough that I'm getting basjoos-caliber comments from random passers by:

- "Is that electric"?

Two people figured it out right off the bat though:

- "Aerodynamic modifications?"

One visitor to the next door neighbour's was really interested. We talked about Kamm, the ideal teardrop shape etc, before his wife called him to bring in the wine for dinner!

[Will]

Check this one out... I know this Metro is electric, but I love the chopped top.

[MetroMPG]

Yeah, that one's a beauty. Lower Cd and A. It's been jawboned before:

Crazy aeromodded Metro - chopped & teardropped

[cfg83]

Will -

Originally Posted by Will

Check this one out... I know this Metro is electric, but I love the chopped top.

I'd like to see someone do that to a Civic VX Hatchback, and Wala!, you'd have a 3rd Gen CRX!

CarloSW2

[MetroMPG]

I just realized I can now no longer carry my bike on the rear hatch rack. I hardly ever did in the first place, but there you go. Moral of the story: aerodynamics are bad. Buy an SUV.