They crushed the pipe because of assembly line installation ease.
The number of holes is not the only parameter that determines flow. You have to also consider the area of the substrate as well as the frontal area of the converter case, the shape of the case, and the transition from the pipe nipples to the body.
Magnaflow does an excellent job at maximizing converter flow. If you'd like any exhaust information, PM me here on the forum or email me at firstname.lastname@example.org
Jeepforum members get 10% off my Kolak Exhaust by the way.
Originally Posted by firsttimeZJ13
My guess would be more flow with 400 holes. Anyone know why they crushed the pipes anyways??