BevanWright,
Ok, I will throw in a few simple things.
1st. Front splitter, proper design with ramp up into wheel wheels. Note: not an air dam. A splitter. Look at some of the current LeMans cars, old WSC stuff etc. for ideas. You wish to control the underbody airflow, not stop it.
2nd.. a rear diffuser. The one shown on the black car made of alloy has too high of a divergence slope. It will stall early and not produce the downforce that a shallower curve will. You will need to extend the aft edge past the body at least 10 inches. (This is due to the rear body shape of the Cobra.)
3rd.. If you put on a rear wing, it does not have to be as large as you are speaking of. It needs to mount behind the rear of the car and about 8>10 inches above the rear deck level. This will be primarily used as a trim device and to help create low pressure above the diffuser.
4th.. Front radiator opening. The best treatment is an alloy or Lexan plate that completely blocks the opening. This should be mounted on the inside of the opening flush with the rolled edge. (Note: use a very strong mounting method as the pressure on the plate will be fairly high.) You will need to add air slots or holes to this plate to provide flow to the radiator. I have found that the area required is quite dependent on average track speed. It is best to test various opening areas to find what works for the assorted tracks that you run.
Just a little hint here: You need much less flow area then you might think for cooling.
5th. Install louvers in the bonnet on either side of the scoop. The more area the better. Run them as far forward as possible.
6th. Vent the front wheel area to the sides. The undertray should come as close to the rear of the tire as possible to keep the underbody flow from mixing with the wheel well flow. Once again look to modern Lemans type cars for examples. Louvers on the upper surface of the fenders starting ahead of the front axle center line and carry back to the rear of the tire are also good.
7th. Seal up the wheels wells around the rear tires. Get these seals as close to the tire as possible. It is much better to stop the air from entering than it is to try to evacuate it.
Also, aero work is not going to help low speed traction out of corners. (50>80 mph) This is mechanical grip area. Look to your spring and damper rates to help in this area.
That’s all I have for to offer for free. Anything else makes the clock start running. (I do after all get paid for consulting on this type of stuff.) If I say too much, my customers will cease to pay me. My mortgage folks would not be happy. Not to mention the wife.
