e
The flow does not have only influence at the peak power....
5-10%?<---these are also just suggestions.As Sonic Speed mentioned right,SOMETIMES more/less.
Each layout has their dis/-advantage what perform diffrent at certain circumstances...
The fuel mix,(flow speed) changes by creating ur own ramp...but too MUCH aint too good as long as u respect the other factors like for example the precompressure.
By creating a too high Volume(taking too much off) could have an negative result.
So keep the compressure and precompr. in mind...
I ve seen for example many tuner who let the the upper corner to the boostport sharp and cornered...Also seen that many leave the crankside(the wall in the middle next to the crankshaft)untouched...
For instance there is many diffrent theories and u cant tell for sure which is defenetely the best.
I doubt some1 here has its own dyno at home,doing step by step and testing any change XD.
I recommend u the 3rd pic of ur last post,cuz i dont like to work with chemical metals to optimate the flow curve
Btw,as easy at it seems on the pics,the practical stuff could turn out as a real challenge