I embarked on a DIY installation of a fabspeed exhaust. Unfortunately 6 of the 8 studs on the turbo connecting to the cats backed out instead of the nuts coming off. Should I reuse these studs or get new studs and nuts? Do I need to do something special to put the studs back in? This exhaust installation has been a serious pita. My ratcheting wrench didn't fit onto the nuts.

 

That's common
just double nut them and reinstall. They are designed for the life of the car. I've reused the studs multiple times.

 

The factory nuts are a one way lock type so its pretty normal to undo them and have them lock on the stud and pull the studs out of the turbo housing. In a way, pulling the stud out is a good thing because it allows you to fit new studs and nuts straight up which is the better way to do this install as the ones that have the nuts come off will leave a degree of thread damage on the stud anyway. The only reason the nuts come off is because the stud is so frozen in the housing. So, then to get the studs out means you run the risk of snapping them off in the housing if you are not extremely careful and even then they may refuse to budge resulting in all sorts of specialist tricks to get them out....so best to recover the damaged thread to fit a new nut on. Putting new nuts on a thread damaged studs will only cause further damage to both new nut and old stud thread so thats when you are best using a die nut to clean up the stud thread prior to fitting the new nuts....that is if you leave the studs in place rather than risk removing them. Yep. This part of the job can prove to be a real PITA. Best to have a new set of nuts and studs on stand by...and a female die nut and a male thread tap for the housing threads. The 996tt ones are better as they dont have those rotten one way lock nuts that the 997tt use so best to use those on the re install, Have fun .