Apprehension over header bolts

[derfo]

I have done the first service on my 02 Boxter S. All went well, oil change, LN spin on adapter and filter, K & N air filter, gearbox oil change, new set of Boch plugs and I cleaned the MAF with some a fine haired brush and electrical parts cleaning fluid. I was quite surprised when I took the MAF out that it looked spotless but I cleaned it anyway. By the way there are two torqs screws that hold the MAF in its housing, one of these was rusted solid in the plastic housing so I had to get the head of the screw and leave the stump in. I fixed it back with just one screw for now,it seems fine but I will sought it proper another time. The car has done 78,000 and didn't seem to have had the MAF off before I did it. I was told they didn't usually last that long. Anyway I know this is going a long way round to the subject heading, but it is connected.
I have in mind to fit a Fab speed full exhaust system on my car, well when I did the service I noticed how rusty the bolts on the headers looked. I thought its just like me to buy the full system, which is mega bucks to me and then a bolt or two snaps off. The headers look like they have been there without being taken off from when the car left the factory. I think Wayne in his book said in one place the bolts have a tendency to snap. If they do what happens then, is engine out, heads off and Helicoils ? can the job be done in situ ? can it be avoided in the first place by heating the bolts up, and by the way on this point how does heating the bolt up help get it out, it seems to me it would swell, can someone explain the science behind this ? I really want to fit a good exhaust system on my car using all the right fasteners etc and once you start at some stage there would be no going back, I would appreciate some comments on this subject and especially from those of you who have done the job before.

[WhipE350]

I heard heating them up too helps. I would think some type of liquid wrench over night on them would help too. Your questions are good, I will be interested in the answers too. I was looking at the whole Fabspeed system too Once you get it on please post or PM me how it turns out...very interested.

[matt demaria]

I had all but one break off on the left side of a 99 996. If you are very carefull you can drill and tap for an 8mm. Make sure you have a drill bit sharpener. Getting the engine hot cannot hurt but it is no guarantee.

[mjj0000]

I too would like to hear from others on this,

I have been told to use an acetylene torch to heat the bolt till red hot. I've had good luck using this technique on rusted nuts, but have never been called to do this on a bolt.

[mikefocke]

If you wander over to PedrosBoard you'll find a cautionary tale from a few months ago from a guy named Maurice complete with pictures of all the steps he had to take to deal with frozen/broken header bolts. Compare your ability to his as you consider if you want to do this.

[mjj0000]

Mike, can you provide a link? I searched on every combination of Maurice, rust, frozen, header, exhaust I could think of and came up empty.

Thanks,

Michael