make 225 sound better?

got a single system on my six long long 2 into 1 set of extractors 2.5 inch all the way to the muffler which has a 2 inch tial pipe. sounds like a six normally
got a y pipe just before rear wheel with a side pipe in front of rear wheel
shim blocks off the side pipe normally

take out the shim when I want to sound like a riot in a trombone factory...its quite offensive makes small children cry

Dave