I will soon see how much downforce the front has when it gets to the track. The splitter has a much larger surface area than the bumper overhang above it. And the wing is pretty big, so it will need downforce on the front to even out the aero balance. I think it will work fine. The car tends to oversteer at Phillip Island, except for one fairly high speed corner that goes over a crest. So I will be able to tell straight away if it's not working.
I have been told this design won't wok for many reasons. Another is the air will be pushed out the sides and won't stay attached down the sides of the car. Air can not stay attatched at the wheel well opening. The air is very disturbed coming out from there.
At the end of the day, lap times don't lie.

So much still to do, but the skirts are on, just reusing the old ones. Mirrors are on, uprights are on, some stickers are on. Wheels have tyres, and there on..

http://i65.tinypic.com/1418jgw.png

http://i63.tinypic.com/osrj87.png

I made a flat floor between the chassis rails from the front splitter all the way back to a small rear diffuser. The side skirts make what look like tunnels down each side between the chassis rail and the skirt. I have braced it all, and it seems solid enough. Even making everything out of lightweight carbon fibre or this alloy sheet, it still adds a considerable amount of weight to the car. I am hoping the drag reduction helps and overcomes the added weight.
http://i66.tinypic.com/maxn2d.png

Having the bracing in the ideal spot, going diagonally from the top is best. But it means a lot of drag and disturbed air in front of the wing. This is an experiment, and if it works, I can make everything stronger and do away with the braces. But there is a lot more time and money involved in doing it better. This is a relatively low cost set up. It actually has cost me less than $100 all up. The cloth and resin was old stuff I had spare, plywood was left over. All I had to buy was $60 worth of alloy sheet.

I haven't updated this in a while. I did the State Time Attack round. The car went well, but the aero had too much drag for a stock 1.8. It did go half a second faster, but top speeds where a lot lower. It was fun holding it flat around the high speed corners.
I went back with the smaller wing and normal front aero. But it rained all day, so didn't get to see if it wa ps an improvement.
We made a video of the new production Fastbacks for those that receive them in big boxes. Enjoy-

And a pic from a hillclimb I did a couple of weeks ago.
http://i63.tinypic.com/21wfte.jpg

The big overhang of the splitter was too flexible, so the whole car shook at high speed. Plywood is not an ideal material, it's not stiff enough. Next one will be honeycomb or expanded alloy.
The guy that did the video makes it look semi professional. I noticed it's got over 10,000 views last time I looked.