Anybody know the correct/recommended helicoil and stud size for an EA82 exhaust stud replacement?

Thanks,

m10/1.25

Just an alternative that's cheaper than the heli-coil kits.... you can run a 7/16" x 20 tap into the existing hole with no drilling at all. Buy a tap, and a bottoming tap (or just cut the end off of a regular tap to make your own), and just run them in there. This avoids drilling, which you would have to do with the heli-coil kit, and it's much cheaper (about $10-$12 for the taps, versus $30 - $40 for the heli-coil kit). Going up a size makes it stonger too. And if you decide you don't like it later, you can always still do the heli-coil!

 

You can then replace the old stud with either a stud or a bolt - use stainless if you can get it. And don't forget a flat washer and lock washer as well.

 

GD