Jump to content
HybridZ

what size K&N filter do I want for cold air intake


jmead

Recommended Posts

I've got a MSA-style cold air intake tube coming from eBay minus a filter. I decided I'd rather have a true K&N rather than the "K&N-style" filter it was listed with. I was wondering what size/shape k&n filter I should get in order to maximize filter size yet minimize the chance of it rubbing on the body or just not fitting entirely. I will probably order this from summit, but if anyone else has any recommendations on a better place to buy K&N filters that would be great too.

Link to comment
Share on other sites

how does it come out into the front of the car, does it make a 90 degree bend and point towards the passenger side of the car, if so, you can run any air filter, i assume its a 3" inlet right?

i would use one for a mustang 5.0 , they are HUGE. i saw a zx with one once that was like a foot and a half long!!!! i would like to run one like this someday, but they are dang expensive, like 150 or something like that.

summit is probably your best bet for it.

Link to comment
Share on other sites

I bought a round cylinder K&N for my homemade cold air intake with 3" inlet. It is 4" by 9" and from Summit racing was $35. It has a galvanized end cap with a stud for a mounting bracket or strap. The tapered ones are more expensive, so seemed a no-brainer.

Link to comment
Share on other sites

Per K&N the formula for air filter size is:

 

A=CIDxRPM/25,500

 

A= air filter area

CID= cubic inch displacement

RPM=max engine revolutions per minute

 

I never knew, but ASSumed the area is the general outside deminsions, not the surface area of all the pleats.

 

Will Piatt

Link to comment
Share on other sites

Per K&N the formula for air filter size is:

 

A=CIDxRPM/25' date='500

 

A= air filter area

CID= cubic inch displacement

RPM=max engine revolutions per minute

[/quote']

 

Let's plug some real numbers into the formula. Let me apologize in advance for not remembering my math skills. I'm sure this answer will be obvious to some of you on this forum.

 

CID = 183

Max RPM = 7000

 

50.24=183x7000/25,500

 

I have a K&N part# RF-1039 which has a 6" long round tapered element.

 

How do I compare the 50.24 to this element?

Link to comment
Share on other sites

Just assume that your element is round and not tapered, use the smaller diameter, let's say 3"? and you can do 2*Pi*1.5*6=56.62. You actually have a little more than that because of the taper, but me old brain doesn't recall the formula for surface area of a cone. :bonk: The round one I have, 4*3.14*9=113.04 in^2

Link to comment
Share on other sites

  • 2 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...