wondering how I would go about replacing the bolts on stock manifolds?

 

huh?

Just a guess but, unscrew old bolt, screw in new one?

 

well, idk, its almost like their stuck in there and spot welded or something...are these reverse threaded perhaps?

 

Exhaust manifolds? They can be difficult- they tend to rust out. I have had best luck doing them while hot- you need to wear welders gloves, but the heat loosens the corrosion. Otherwise, heat them with an acetylene torch- propane isn't going to throw enough heat- get them glowing cherry red, and they come right out-

If they snap off, take the whole manifold off- there may be enough of a stub sticking out, if you are lucky, to get them out with vice grips- otherwise, it can get real ugly-

 

yeah i have them off the car, so that'll be easy enough to do.

Thanks guys.

 

lmao ohh are you talking about the 3 studs in each manifold? I thought you were talking about the manifold to head bolts...

I replaced the 3 collector studs on both my manifolds since they bent to hell.

I heated up the cast iron around the stud with a vutting torch, and simply unscrewed them with a big crescent wrench.

I used a cutoff wheel on the back side to flatten the shoulder so I could TIG weld the appropriate sized bolt in place, after drilling the threads out.

I also over sized the 3 holes in each collector flange so it slides over the 3 studs/bolts easily without binding.