Couple of questions

Hello, I have a couple of question about different things. Only changes on my ender 3 is aluminium extruder, glass bed and 1.1.5 silent board, raspberry pi for octoprint.

1. Printing with PETG - Is there anything special i need to upgrade on my ender before i can print with PETG? I heard capricorn tubing is needed, i have one from this package :

https://www.banggood.com/Upgraded-Long-Distance-Remote-Metal-ExtruderLeveling-SpringPETG-TubeMK10-Silicone-Case-Kit-For-Creality-CR-10-Ender-3-3D-Printer-p-1434018.html?rmmds=search&cur_warehouse=CN

But it says " cloned capricorn tubing ", so i am not sure if that would be good enough? Is there anything else that is recommended ?

2. Printing with 0.8mm nozzle, same question here about any needed upgrades ? I assume better cooling

3. For setting up direct drive with current extruder, i would need extension cable, what type of cable is that ?

4. Is there any way to speed up the printer, without upgrading to new motherboard?