Total weight of diffuser and feeder system was 22 lbs. Carbon fiber diffuser weighs 7 lbs. If the ride height is 3" and the C6 Daytona APR wing is set at 12' incidence and the C6 spoiler is in place, the load increase is 280 lbs at the axle at 130mph with a massive drag de-crease. Run down tests from 150mph verified. Suction peak is at the ARB or sway bar so the center of lift migrates toward the cg at speed. The wing augments diffuser efficiency and by so doing reduces drag under the wing. The ramp chord is 17' incidence. Total downforce at rear was 520.(load censors) Wing incidence is track specific. The car had 560 hp at the rear wheels with 4:10 gears. Ride height and droop is controlled with coil/overs and engine and exhaust was fenced down the center. See cover over the headers. Side feeder and ramps have the same area as an Enzo Ferrari. Coil/overs saved 10 lbs total and removal of stock exhaust saved 30lbs. Central muffler was for street. Profile or section math and load censor reading was 20% optimistic because of too may variables. Total cost of construction including axle back exhaust( doesn't include computer work and coil/overs) for two cars was over $12 000. The street version is purely for bling and costs a whole lot less. Lap times is the true measure and they were lower at all the south eastern tracks. This was 10 years ago so I can't remember too much. The C7 diffuser has to stick way out back to achieve the same area as the C6.