I have recently had a ECU re-map from power engineering and the next mod suggested was a down pipe. I have obtained a down pipe now and was woundering if I install it now after the re-map will I experience any difficulties i.e running lean, or not boosting properly, problems with ignition timing etc. After a few more mods I will go back down to have the ECU adjusted to the new mods.
Car is a MY96

Any advice would be appreciated.