turbo lack of punch?

[nitroman]

If you're into boost creep with the Peco it shows how much a catalytic-converter cuts down on power. That a 2.25" w/o a cat can have creep while a 2.5" with cat can't... wow. I say this knowing that putting a cat on a 2.5" mandrel system cures creep. (but so does porting the wastegate) I've run all 3 ways with a 2.5" exhaust.

Think about it. That is why the ID of a cat increases so dramatically over the ID of the exhaust pipe serving it. I wonder if, in the mathematical calculation, the original "free-gaseous" volume of the pipe is maintained inside the cat.