Options if head is stripped out at manifold studs?

When I bought my S12 the morons that had tried to work on it before stripped out the rear top two exhaust manifold studs and installed larger bolts... well they're almost stripped now, and I'm trying to figure out what my options are... Anyone know if they make a plug that I could rethread the head for and install, then put new studs/bolts in to secure it?? I really don't want to replace the head... if it comes to that, I might just drop my CA18DET in it and be done with it... =(

Is it beyond the point of using a tap and die kit to clean up the threads? Most other options will require you to remove the head and bring it in to a shop. It can be saved, but whether it's worth your time and money is up to you.

Should be able to re-tap it and use a heli coil and possibly use the same size stud. I had to do this on mine, but it was so bad I had to heli coil it for a 12 mm stud instead of a 10mm. Haven't had any problems sense.
I think Bart has heli coiled a couple of his too.

Well the problem is they threaded it rather large... the bolt I'm having to use BARELY fits through the hole on the manifold, and hte head of hte bolt barely has enough clearance to turn...

http://members.cox.net/84200sx18t/200sx16.jpg

Those two you see up top with the lock washers... those are the ones I'm talking about... they're like almost NICKEL sized bolts... well maybe not that big, but definitely bigger than a dime... they're also standard thread I think... like I said, the bumpling idiot DIY mechanics that had it before me did the shit... I'm just trying to keep my manifold in place... =(

With my car the rear 3 manifold studs were getting loose when I first got it because the factory threads are aluminum in the head and aren't very deep. My dad and I tapped the threads and modded the tap a little so that it cut until it hit the stop of the hole. this worked fine and to prevent future problems we bought some hi temperature grade loc-tite and used that so they wouldn't come loose again. The high temp loc-tite I found at a local Smyth automotive but be warned it is fairly expensive about 10 bucks for a tiny little bottle.

Well I know how to tap and rethread the hole... the problem is the bolts I've got in it now are almost TOO big to tighten (the one on the bottom I cannot tighten because its simply too tight!). So I need to find a way to go back to a smaller "stud" so I can actually tighten it in place... going up a step in bolt size will make it either A] not possible to go through the manifold hole or B] impossible to tighten, unless I get a hex cap head bolt... which is an option I guess... just don't know of any bolts THAT BIG...

helicoils are your best option. http://www.contractorstools.com/helicoil1.html

Yep, heli-coils work good, and I've got a form of helicoils that is called "Time-Sert." Really nice setup, has the thread inserts already made with a chamfer on if instead of just coiled up wire like a helicoil. But heli-coils work good too.

BTW, the threads in CA18/CA20's are TERRIBLE about stripping out. I guess once the aluminum gets hot enough times, it just doesn't want to hold on any longer. When I pulled the CA20 out, it had 3 holes that the threads came out with the bolts...

yep keith! i had the same. i now have helicoils in mine. one of them is a m12 helicoil. its the best option and since mine was done i have had no problems at all, i wish i had got round to doing it sooner rather than replaceing the gaskets and retapping every fortnight!. They can be helicoiled with the head in the car, mine was but they will have to remove the manifold and turbo for acsess. Shouldnt cost you more than 4 hours labour tops, bare that in mind if your looking fr someone else to do it