Does anybody know what's the max a 317 head can be milled without having any problems?

 

On stock castings I would only mill them enough to clean them up, not any more.

 

Do you mind telling why is that?


I sen't a pair of stock heads to have them ported by professional porter locally, and I wanted to have them milled like .045, but I don't want to have any problems with the intake not fitting.

 

Thanks everyone