So long story short.. awhile back when I was putting my turbo on and tightening the nuts for the exhaust mani, I cranked the very front one a little too much and stripped it out from inside the head. I said F-it and kep procrastinating and never did it. This week im putting on my new S15 T28 and I want to fix it before I put it on. But I don't know what size to drill it out to and which helicoil to use. Can anyone help me out?

 

do you know the size of the stud? i think its 10 x 1.25.
went on google, typed in 10 x 1.25 kit, you get this:
Amazon.com: Helicoil 5543-10 M10 x 1.25 Metric Fine Thread Repair Kit: Automotive
kit has everything except for the drill bit i think, but it tells you the size in the instructions:
Drill Size 13/32

 

i found that the stud is M8x1.25. but thanks for pointing me in the right direction.

 

If you go to a local Ace hardware store they carry the helicoil you need in stock. I'd look there first, then possibly Lowe's...

 

i think napa might also, i bought just inserts there awhile back

 

IIRC the helicoil is going to be one size up from the thread size you are trying to repair meaning you'll probably end up tapping it to m10 X 1.25. The outer threads on the insert will match that size while the inside will be the size you are replacing. The procedure should be drill out threads, tap to size X, use driver to insert helicoil, break off tang on inside of helicoil allowing stud to bottom out in new threads.

 

Exhaust manifold studs are NOT M8

Definetly an M10 bolt.

The helicoil kit should come with everything you need other than the correct drill bit size.

I'm pretty sure they dont use a "next size up" on the tap either, believe they're specific to the coil inserts which are the correct size for the thread you're trying to repair.

As for sources, autozone and advance both carry quite a few helicoil kits and inserts, napa has them also you've just got to ask, grainger is another good one.

 

^ like i was sayin
and try to get a t handle, makes it a lot easier.
also use some lubrication when tapping it and make sure you go like 1/2 a turn then back 1/4 and keep repeating like that