Print with a brim and supports. I kept printing different versions until the walls were thick enough and airtight. Check for air leaks by capping one end with your finger and blowing through the other end. Use this part cautiously at your own discretion or as a placeholder in assembly. The area around the port gets quite hot to the touch, but not scalding.

I attempted break ins and two races with this made from clear pla and only completed a few laps due to throwing a chain early in each race. I’m grateful because if I were you, I would be weary running this a full race distance. Right now the top of this part doesn’t cover the area around the port all the way and it can get a little loose. I’m still skeptical but have it equipped until I can get a proper machined version. Photo taken after a few attempts of breaking in the engine on a stand and 4 race laps.