Mugen's testing regimen doesn't come cheap, and it does have an effect on the parts' retail prices. A quick comparison of RSX kits on the Web showed Mugen's full kit, including the front bumper and undercover, side steps, rear wing, and Aero hood, retails for $4,780. A full aero kit from Wings West, including front and rear dams, fender flares, and rear wing, sells for $1,466. For '96-'00 Honda Civic hatchbacks, the story is pretty much the same. Mugen's full Aero kit, with an Aero bumper, wing, side spoilers, and rear bumpers, sells for $3,600. A Kaminari full fascia kit and wing for the same car costs $1,334, and the Wings West version goes for anywhere from $1,100 to $1,200, depending on your choice of wing. Do you get what you pay for? That depends on how serious you are about form versus function.
A peek inside the Langley Full Scale Tunnel at the Langley Air Force Base in Virginia will give you an idea of just how big a wind tunnel needs to be to test fullsize vehicles. That's an actual NASCAR Taurus parked in front of the two 35-foot-tall fans, which are driven by 4,000 hp electric motors. The tunnel's test section, where the cars, airplanes, and other objects are placed during testing, is 30 feet high and 60 feet wide. While the Langley tunnel used to be closed to all but NASA projects, it's now open for business and operated by Old Dominion University.
The Wing's the Thing
APR Performance's K.C. Chow was candid about his company's-and others'-wings. "We don't recommend some wings for the street. They're going to slow the car down, take horsepower away because they generate too much downforce." And an honest-to-god Funny Car wing, for example, is designed to generate in excess of 5,000 pounds of downforce at 300 mph. Without that kind of downforce, the car would have no traction at all, explained K.C., since the 5,000hp engine could easily blow off even those big drag race slicks. But this radical a wing, and most pro drag race wings, don't make any sense for anything but pro racing. Even street-oriented wings don't really start working until you get over 60, K.C. continued. "Below 50 they're for looks only."
One of the reasons we contacted APR was because of the company's dramatic bi-deck wings. We wondered if they really worked. "Absolutely," said K.C.. "The more decks a wing has, the more downforce created."
Plus, the bi-wing design offers more adjustability to suit road or track conditions. "You can adjust the attack angle of both decks, to dial in what you need," K.C. said. For conditions where cornering is more important than top speed, increasing the wing's angle of attack (tipping it so it's more perpendicular than parallel to the ground) will increase downforce, but will also increase drag. When top speed is paramount, the angle of attack can be lessened to reduce drag, but with a corresponding reduction in downforce. Wing design and shape are just part of what affects its aerodynamic performance, K.C. told us. Where you mount it, and how high you mount it, also makes a difference. With some wings, if you mount them too close to the car's body, the negative pressure area off the bottom of the wing creates negative pressure on the surface below it, and the two pressure areas cancel each other out. A higher wing pedestal will separate the wing from the trunk and better balance the forces from each.
"It doesn't matter how much horsepower you have," said K.C., "without the right aerodynamics the car won't go anywhere."