How would I do this?

Hello I have a 1990 firebird formula and after changing the exhaust to a catless side exit the car has been dropping to lower rpms at lower speeds and actually stalling, it also has a egr and smog delete and tune, is there any obvious change I could burn into a chip that would keep it from stalling at low speeds? I have a datalogger and the blm reads 122 or lower at those lower speeds while it stays at around 128 everywhere else? Would I adjust the blm at lower rpms so it produces more power and thus doesn't stall?