Originally Posted by IlChengis
Someone (sorry, don't remember whom) posted this
link a couple of weeks ago and I found it extremely interesting.
If I recall correctly, someone on this Forum had custom 3" midpipes done that tapered down to 2.5" at the mufflers. I suppose such setup could have easily handled over 500whp given the reduced backpressure caused by moving the taper so far down the exhaust.
My brother who is a engineer, knows a lot about this topic said 3" downpipe even when tapered to 2.5" would yield larger gains than a 2.5" downpipe. Im not sure how he figured that, but I will ask him when I see him.