3" exhaust? 2.5" exhaust...??

I also see things like this; 2-1/2 for the street, 3 inch for the track, small block or big block, it doesn't really matter.
On the street, unless your a street racer, you'll still have great power and decent sound control with the 2-1/2.

When your at the track, sound control is best answered with 3 letters. FTW!