This is EXTREMELY interesting. Would like to do the same and also fab a duct with a smaller opening to the radiator. The desire is to get aero such that my 240Z is stable at higher speeds and also get VERY good cooling of the radiator.
Ok here is my thread about my revised bell pan. I am taking my experience with the current pan' date=' and expanding on what I have learned from the wind tunnel testing. That is why I have put it in this forum. The belly pan in the pic below has been on the car for about 10 years, and has resulted in the car being very stable at highspeeds beyond 140mph. I am documenting my redesign and extension of the pan. I am also redesigning the airdam itself. I will attempt to resculpt it using fibreglass to cover the front wheels better, and be a bit lower. I have removed my long used lawn edging airdam extension, that has been on the car for about 17 years.
I have started by redesigning my lower rad block off plate. I have done this to improve the fit, and clean up the look a bit.
Next I will begin prepping the airdam to reshape it using expanding foam and then laying fibreglass to blend and bond to the airdam. I hope "while I'm at it" doesn't get the better of me. Once the airdam is modded, I will make a new template of the bellpan. It will be a two piece design, that will end at the transmission. It will stop where ever it will make mounting it easier. I will also likely add small fins going front to back, but I will get into that as I build my mockup.