tees

Hey guys, I'm a college student looking to machine out some car parts out of billet aluminum. This seems like a pretty bougie way to go about this, but it does seem like the OEM parts can cause issues, and I feel like for show cars, or people that just want their rig to be a bit more sick than...

How often are you guys changing this out. I know it's a maintenance item but do you do it at 30k or what. I need to change the heater tees also. I guess do them both at the same time. and same intervals? Thanks,