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         I thought I'd show you the latest
        engine parts. I wanted some good air flow so I went with the K
        & N air filter. The element is 14" X 4" but is 5
        1/2" tall overall ( which including the base). The base sits 9/16"  above the carburetor
        which is just right. I had a choice of different "drop-base" models but I
        didn't think I would have the room and I was right after seeing how this
        one fit. This one is close to
        the top of the fuel bowls now so the other ones wouldn't have worked.
        How did I figure out how large of a filter to buy? It's easy....just use
        this simple formula and see for your self.  
        
          
            A =  CID X RPM 
                        20,839 | 
            A= Area of filter 
              CID = Cubic Inch Displacement 
              RPM = Max RPM | 
           
         
        So we have... 
        CID = 434  - RPM = 7000 divided by 20,839 = 145.78 
         
        Now if your using a round filter like I am, use this formula. 
        
          
                          
              A 
              H =    D X
              3.14    + .75 | 
            A= Area of filter 
              H= Height 
              D = Outside Diameter of Filter 
              3.14 = Pi 
              .75 = Rubber End Caps | 
           
         
        So now we have... 
        A = 145.78 divided by (D = 14" X 3.14) + .75 = 4.27" 
        This is how you calculate the size of the
        filter you want. Mine needs a 1/4" more in height at 7000 RPM but I
        won't be living there so this should be more than enough.  
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