AOD help need help bad!!!!

[Silver5.0]

Hi I was wondering how high RPM'S are suppose to go on a aod. Because my old aod every once in a while could go up to 5000rpm's and i would love it, but rarely did it do this.Anyways I just bought a tci street fighter aod tranny and it only goes up to 3000rpm's strong then maybe gets up slowly to 3500, just bought it, keep in mind today. Could it need time to break in, I heard it didn't though.Well what i really want to know is why does it only go up to 3000rpms strong could it be i need new spark plugs and cap and rotor the whole tune up,All i have done to my car really is 3:55 gears,pulleys,cat back flows and headers,and suspension.Please help.also i got a brazed converter could that have a reason to it.no stall speed though on it.