Calculating required exhaust port area?

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Wayne Miller
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Main scooter: Vespa 50 Special (Rotax Proto)
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How do you calculate an exhausts port area?

Lets say I want max power at 10000rpm and I have an exhaust port duration of 190 what do I need to do next to determine what the port area needs to be?
Stay tuned..............
wezly
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Wayne Miller
registered user
Posts: 345
Joined: Wed Jan 07, 2009 12:52 pm
Main scooter: Vespa 50 Special (Rotax Proto)
Location: Rothwell, Northants
Contact:

The books usually tell you to measure your chordal width to use in determining you port area. I want to do it in reverse and determine the required port area and from that determine the chordal width. ie this is my cylinder volume, this is my port duration and this is my port open time at this rpm what is my required port area. Im guessing there is a formula somewhere as you can do this kind of this in some of the available software.
Stay tuned..............
Avantone
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Are you after port area or mean port time area?
Tony

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Wayne Miller
registered user
Posts: 345
Joined: Wed Jan 07, 2009 12:52 pm
Main scooter: Vespa 50 Special (Rotax Proto)
Location: Rothwell, Northants
Contact:

Hi Tony,

Im after port area for now :fb:
Stay tuned..............
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