This is the question that generates returns. A filter arrives, the owner opens the airbox, and there are two housings. Or the listing says "full kit" and they are not sure what that includes. Here is how the three manufacturers we carry describe quantity, and which Porsches quietly need more than one.
The three conventions
| What you see | What it means |
|---|---|
| Sold Each | One filter in the box. If the car takes two, order two. |
| Set of 2 | Two filters in the box. One order does the whole car. |
| Full Kit | BMC's term. The box contains every element the listed applications require, however many that is. |
We put the quantity in the title of every air filter listing for exactly this reason. You should not have to read to the bottom of a description to find out whether you are buying half of what you need.
The cars that take two
Most Porsches with a flat-six mounted behind the axle have a single airbox. The ones that do not are worth knowing about.
911 Carrera, 991 and 992
Twin airboxes, one per bank. Both K&N and aFe supply these two per box, so a single order covers the car:
- K&N 33-2484 — 991, two per box
- K&N 33-3153 — 992, two per box
- aFe 30-10242 and 31-10242 — 991, two filters per part number
- BMC FB01075 — 992, supplied as a full kit
911 Carrera, 997.2
Same arrangement. K&N E-1999 is two per box, aFe 10-10126 contains two filters, and BMC FB550/08 ships as a full kit.
Boxster S and Cayman S, 981
aFe 10-10131 and 11-10131 are both set-of-two. The BMC FB750/04 covers the flat-six 981 and 982 as a full kit.
V6 Macan — the one to watch
This is the trap. BMC FB867/04 covers both the 2.0 four-cylinder Macan and the V6 cars, but BMC marks the V6 applications as requiring two filters — and the part number is supplied as one. Four-cylinder Macan owners order one. Macan S, GTS and Turbo owners order two.
The aFe equivalent, 10-10144-MA, ships as a set of two and covers the car in one order.
The cars that take one
Everything else in the catalogue is a single-filter application: the air-cooled 911s, the 996 and early 997, the 986 and 987, the 718 flat-four, the first-generation Cayenne, the 970 and 971 Panamera, and all the transaxle cars. If the title says Sold Each and your car is on that list, one is the right number.
Before you order
Two habits worth adopting. First, open the airbox and count the housings — it takes a minute and settles the question permanently. Second, check the engine, not the badge; the 718 range in particular splits between a turbo flat-four and a 4.0 flat-six that take entirely different filters.
If your car is not obviously covered above, the chassis guide lists every application we carry with its quantity.