Is this that hard a question?

Ok so I am looking for air filters for my 911 project and I sent this Email to a large aftermarket manufacturer.

Email # 1 "How do I calculate pressure drop at a given CFM for your dual stage filters. Do you have a recommended square inch of filter per CFM? Thanks "

They returned Email #2 "Hi, We offer much different porosity. Depends on the foam combo selection. We do not use any standard of CFM per sq. inch.

What is the project you are working on…?"

So I sent Email #3 XXX, I would like to use two UP-6XXXX on my Subaru powered porsche 911 project. The filters will be in the rear wheel well with a slash guard for water. However this location may be closer to an off road application than an engine bay? I have already purchased one of the filters for test fitting and it seems like it will work fine. I need above 420cfm with the filters a little dirty. They will be serviced often.

I did not want to say what company this is as they may get back to me with good info. But it has been a few days now. I want to know how in the word can you say your products add performance when you can not answer simple technical questions? I wonder if it would I blow his mind if to ask how small a partial his filter could remove. I do not think he knows. That seems like something you should know if you are in the filter business.

I bet they have someone who can answer. You should try calling.

Yup. Hard question.

You're talking to a sales rep. He probably only know's what filter goes on what car.

You need to talk to someone from design side. Give them a call.

+1 I find I get better results for oddball tech questions if I am talking to a people person. Just today I called Berryman products about their Chem Dip carb cleaner being put in an ultrasonic cleaner. I was called back within 3 hours by a guy that could explain the difference betweene the old formulations and the new EPA compliant formulae. He even knew the name of what chemical to look for on the ingrediint list on the can. I was impressed. In case you wondered I cant use my old formulae but if I buy a can of new stuff I can.