This cone-shaped air filter from K&N is designed as an extension for the 3806 Swift Sports 2000 racecar air scoop, but it can be adapted to a wide variety of custom applications. Both ends are open and flexible enough to conform to an oval or rounded rectangle.
Inlet: 8" Outside Diameter / 25" Circumference
Small End: 4.87" Outside Diameter
When this filter extension is combined with part #3806 they form a 27" long unit with a huge 872 square inch air flow area. Even if this combination were to become 75% clogged, it would still flow enough to feed a 454 CID V8 revving to 10,000 rpm!