Headers are a huge pain!
 

So I bought some new headers off ebay for my 1998 box with 91k miles on it. I had read a lot of articles on people breaking the bolts off in the head when removing headers, but I thought mine would be easy... I was wrong. I ran the car for a long time before starting the project to try and heat it up a good bit hoping, this would help the bolts come out easier. Once it was hot I soaked the bolts in PB Blaster and started on the left side header first; I got all the bolts off with a ratchet except one that broke. The one at the very front of the car, so I drilled it out and tapped it. The right side didn't go so well, I got the impact hammer and a propane torch and heated each bolt for about 5 mins then tried the impact hammer and I still broke every bolt except 1. I am going to continue this project tomorrow, I just wanted to see what people had to say on the issue. The only way I know to get these out is start off with a small drill bit and start drilling and go up in size until the old bolt is all drilled out then tap the hole with new threads. The only thing is my new threads really are not great... I mean they are OK but I am worried about stripping them out when I go to tighten the new bolts in. Does anyone know how tight the bolts are suppose to be??? Do I crank them down or can I just snug them up?? Is there a better way to do this because I have to do 5 more on the right side, and is there anything else I need to worry about? Any input would be greatly appreciated. Thanks so much!!!

The way your drilling out your broken bolts is good but not the right way. Go to your local auto parts store and buy an Easy Out. It looks like a drill bit that has a reverse thread, resembles a twisted ice cream cone. After you drill a certain size hole (each easy out will say) in the broken stud the Easy Out is screwed into the hole (Lt hand thread) and as its biting in it's also extracting. Works very well and will save your threads.

Good luck.

Had the same problem -although not as many bolts .Tried the ezout approach and it wouldn't budge them ,even with heat .I don't think the propane torch is hot enough-the head is a big heat sink .
Ended up drilling the bolts out and using helicoils .The trick was getting the holes straight and the old exhaust manifold was a good drilling fixture for the ezout drill bit .For the front and rear hole you will need a long drill bit .
Good luck.
Dave

Yeah I tried the EZ outs too, they didnt do one bit of good. The one I did tap I didnt use the helicoils. Should I? Do they make that much of a differnence? The reason I dont want to is because once I do that I am kinda out of options if I mess them up. Thanks!!!

Tough call -The Bentley manual prescibes 17 ft/lbs torque -which isn't a lot .However,the headers and the converter hang off those bolts ...........
In my case I didn't have enough thread left to salvage -you might .Actually there is an optioin past the helicol - step studs -m10 and m8 . Don't understand why they used bolts -the two 911's I restored had studs and were never a problem ..

Dave

I had a similar experience. Six of my bolts broke off no matter what I did. Be careful if you drill them out as I went too far on one and entered the oil cavaity (barely). Luckily the shop just sealed it off and put studs in there instead.

When you are done also make sure you tie back the power steering hose so that it never comes into contact with the headers or you will have a fire like I did. The lucky part was that we had it out right away and there was no damage other than the blown hose and fluid everywhere.

Now that they are on (about 10 months now) they do add a nice tone to the exhaust and have been trouble free.

Chris

Not really the topic but,,,,,,,, PLEASE make sure that power steering lines are away from the headers on the drivers side. I melted one of mine with my s car go headers lucky there was no other problems. You can just zip tie them over alittle if you have to..
my .02

thanks guys, I was wondering how much room I had to play with until I hit an oil cavity... I guess not much. I spent all afternoon on the passenger side and I was only able to get one bolt out. I had enough sticking out to weld a nut onto it and twist it out that way. I am going to go grind the others flush and start drilling. I will let you know how it goes, and I will be sure to post a video and some pictures. Ive got a Fabspeed catback exhaust so with the headers im sure it will sound great! Ill also be sure to watch any AC and power steering lines around the manifold. Appreciate all the input. Thank you!!!

I finally got the headers onto the car, after more drilling and tapping than any project deserves. It doesn't really sound any different but it feels like it has a bit more power up in the top end. Ill post some pictures and a sound clip tomorrow. Thanks for everyone's help!!!!

same problem
 

but, I only had 1 bolt break. Broke the easyout in the bolt trying to extract it. So, I just left it, there is a leak though, is that something that has to be fixed right away or can I just ignore it. Will performance suffer as a result of the leak?

jim

Fix it immediately. Hot, corrosive gases will blow away metal from the sealing surface and destroy the cyl head.