Pete. (l33t FS) said:In reply to TheRyGuy :
The oil filter housing is designed to drain the oil filter when you loosen the cap. This prevents a mess.
A spin on filter would make oil changes a messy nightmare.
It could be a mess, but the aftermarket kit has a Schrader valve on the housing in order to blow the oil out before removal.
Alternatively, you could poke a hole in the top of the filter and use a rubber tipped air nozzle to do the same thing. I did this on the one air cooled 911 I changed the oil on, where the filter is mounted horizontally in the engine bay.
