Bill

Yeah I guess that's the point I was making....but if you take 2( 3/4" x ~3") that's 4.5 square inches of open flow area which is really only about 10% less than the cross section of a 2 1/2" ID open pipe which is 4.91"....acually it's less than that cause the id of a 2 1/2 is smaller than that. If the case was only 1/2 taller overall (which would give you +1/4" on either side of the tube) the flow area would exceed the open pipe. so that case is properly sized for a 2 `1/4 inlet/outlet, what you have is a marketing/cost compromise. Ironically that muff would probably work better as a 2 1/4 with customer provided 2 1/2" neck downs.

Bill, That's a beautiful car by the way, I think I might have mentioned that before...but just in case