As the title states I just purchased a 2014 ZX14r second hand with 15,000 miles great condition everything OEM except Two Brothers slip on exhaust. My question will it make much difference in performance if I switch to a single voodoo full system before getting the ECM tuned by Moore Mafia. Also what other mods should I do before sending the ECM for tuning not planning on racing the bike but want to do all the affordable mods before sending in the ECM.

Any exhaust change is going to move the torque value up or down so any change from stock will be a sort of improvement.

Flashing the ECU will still be within an AFR range so as not to lean out or over rich the tune from stock. So Moore's tune might be more aggressive than Ivan's rich smooth tune.

I'm more of a stock rider rather than taking a chance on receiving a brick or be caught up on an emissions breach and pay to have it revert back to stock.

Wait for other comments of experience rather than hearing my rant about performance tunes.