J head porting

EL5DEMON340 said

I’m just starting, will cut to 2.02. Here is a pic of the guide cut down about .200, and just starting to blend. I’d like to have them flow enough to make 450/475HP so I don’t think I need to get to nuts on them, maybe 240cfm ?

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I know what I’d do and that’s start with a valve job. How do you know how big the throat will end up without establishing the valve job?

Learning to port on the interweb is no different than learning to port reading car magazines.

If you have access to a flow bench us it. The FIRST thing you’ll learn is most everything you read in magazines and forums like this WRONG.

Right now you are just guessing.