It works perfect but it will be a lot louder with the KA than the SR...
I'm running a Buddy Club Spec 2 80mm turbo exhaust on my stock KA...
With my SOHC KA, I ran the stock cat but with the DOHC KA I'm running a 80mm SR downpipe, cat delete, and then the exhaust... It all bolts up...
and here is an old post where Alex dyno'd before and after with a 80mm exhaust on an NA KA... it made more power throughout the entire powerband...
http://forums.freshalloy.com/showthread.php?t=93868