You can squeeze 300rwhp out of a stock ct26, but that doesn't mean it's a good idea. Back when I only had the following:
Lex AFM
RC 550cc injectors
Fidanza LWFW/Stg. 3 clutch
BIC DDP, running open downpipe
Stock CT26@15 psi, falling off to 13ish near redline
I made 289rwhp/295rwtq on a Mustang...