I am thinking about switching out the Harley stage I air kit that I have on my bike now to the heavy breather kit. Bike has cams and pipes and has been tuned via SEPRT. My question is there that much of a difference in flow that i would require a re-tune?

I have been under the impression that the stock throttle body and heads can only flow so much air so that this would be a non issue.

Also for anyone that has made the switch how much further out does the HB stick out in comparison to the stock football?