exhaust help needed

[bkroll84]

Was putting new exhaust on and on of the bolt to the flange that goes on head snaped off what should i do looks like its sealed but wanna fix it

 

[alex456123]

this is common but you need to drill it out, tap it, and put a bigger stud in the head. easy and it will never happen again!

 

[bkroll84]

Well head is all messed up previous owner welded stem on there no way to get off. I am buying the top end from jglock this weekend so i will be running a .20 bored over anything i should do to lower end?