172cc piaggio AC exhaust options?

[bendover]

Aprilia sr125 tuned*

I want low end grunt. Gilera 180cc stock exhaust is very good according to dynos below, but it does not fit ac engine. Is my 125cc exhaust same/comparable to the 180cc stock exhaust?

Catalyzed is supposed to suck, how can I tell if it is cat?

Charts that confirm stock 180 exhaust is probably best. Great resource btw:
www.bike-equipment.net/07_diesunddas/html/upinsmoke1.html
www.bike-equipment.net/07_diesunddas/html/upinsmoke2.html
www.bike-equipment.net/07_diesunddas/html/upinsmoke3.html
www.bike-equipment.net/07_diesunddas/html/upinsmoke4.html
www.bike-equipment.net/07_diesunddas/html/upinsmoke5.html
www.bike-equipment.net/07_diesunddas/html/upinsmoke6.html


Keywords: Gilera runner 180 exhaust, aprilia sr125 exhaust, aprilia sr150 exhaust

* - 172cc bbk, 25mm carb, v force reeds, lc flywheel/stator/cdi. Stock 125 exhaust.