I'm currently overseas and local laws do not allow aftermarket dump pipes, as such decatting the stock dump pipe is my only option.

I should be getting my ECU tuned a few days after the exhaust is done. As such, I really don't want to waste $ on the tune if the stock cats are going to be restrictive to gains.

So in the interim before I get my ECU tuned, will running around with a catback + decatted dump pipe cause any issues with the engine/turbo?