in theory the Porsche OEM paper air filter should offer LESS resistance right ?? than the BMC

 

Wrong. The BMC will flow much more air. Your math is wrong.

 

BMC

 

BMC. Have been using them since i got my 996, love em.

 

Probably the wrong place to ask this question, but does BMC make a filter for 993's?

 

Luis, yes. Check the fabspeed website, I had the cold air box cover kit on my former black 993 - I think it was about $175 and included the BMC filter (Also had the fabspeed mufflers). Call Joe at Fabspeed and he could hook you up.

 

Is there any actual direct comparison testing of the 2 filters on a flow bench? I read a test of a K&N filter vs. paper filters for a turbodiesel pickup truck. They used a SAE filter testing machine that measured airflow new and dirty and filtering efficiency - the % of dirt that got thru the filter. The K&N cotton filter had slightly less airflow restriction but passed much more dirt and became more restrictive when dirty. I can email the posting I saved of the study if anyone wants it. PM me your email. Its a 1.2 meg file.

 

I have read multiple tests which confirm what you have said, will try and find the links.

I personally think the amount of difference between different filters is neglible and in my exprerience I have found that to be true

 

Actually paper filters will typically flow better, square inch for square inch, than any of the aftermarket oiled gauze or oiled foam filters will...*as long as the paper filter is clean*. The benefit to the aftermarket filters is thier size and the fact that they can function better when dirty.

Here's a direct flowbench comparison of a OEM Mahle paper filter from a E30 BMW to a K&N, ITG and Amsoil oiled filter.

The paper filter flowed the best:

http://www.bolhuijo.com/airflowtest/index.html

 

I genuinely think paper filters offer less resistance if you hold both in hands and blow through them you'll see

 

Interesting question. Which are you comparing? The pleat vs. pleat, or cone vs. pleated?

If you do the math, as the guy said....the paper element will flow more air than the pleated oiled cotton filter. Count the # of pleats and multiply by the surface area of each and you will see.
If a filter of the same surface area is to flow more air with the same pressure differential, it will have to be less restrictive (less filtration) period. So to gain one you have to give up the other, I say go with paper if you want, and change it before it becomes really dirty (restricted).