I recently insalled a PC3 on my "02" Busa. Only mod's done as of now are 4into 1 TRS Yosh exhaust and K&N air filter. The only map I could find to download was for a Yoshimura Duplex exhaust and after market filter. At first the bike seemed to idle smooth and the throtle responce was great, but the more I ride it I seem to have a hard time with the bike running smooth at low rpm's. Even downshifting when coming to a stop the bike will want to shut off, almost like it is getting too much fuel. My qustion is should I spend the money to put it on a dyno and have it tuned by a pro? Or could I download a map file for another exhaust that specifies a four into 1, and not a duel/ dupex exhaust. I have a ride coming up next weekend that I would like not to worry with this problem when ridding. I guess I could always put the stock settings back in.