Ok so when removing exhaust to replace head gaskets the 3 bolts that connect the manifolds to the Y pipe broke from being so rusted. So I drilled them out but since there is little room I cannot grab both sides of the bolt in order to tighten. Sooo I was thinking of welding the bolts to the manifold but im not sure what it is made of. Im thinking cast iron but if not let me know.

Also if thats not an option what years manifold will swap on to a 94 LT1? 5.7l

 

They are cast iron I believe.

 

ok well either way im using the coil/thread insert things. You drill out the old thread/hole then tap it and insert a threaded spacer thing that is thread inside and out.

 

yep its that or another manifold. i have a 93 set if it dosent work. i think 93 and 94 are the same. not completely sure. if you have a pipe going from the passenger side exhaust to the intake manifold it would not be the same as a 93 but a 95 to 97, they should be same.

 

yep I have the egr pipe i believe it is going from the passenger manifold to the intake. Good to know. Hopefully the thread insert works though.

 

Once you get the heli-coils in, look into using the replacement manifold studs instead of bolts. And if you use brass nuts to hold the flanges, you'll be able to get them off again easier if you wanted to later. Get the "tall" nuts if you can. And.....Anti-Seize everything.

 

I was going to use some thread lock. Guessing you cant use anti seize and thread lock together. Just use the anti seize and torque em?

 

You can do it that way too if you want, thread lock will act as a thread protector. Don't use the red, and see if you can find the high temp version. But honestly, I've never had a flange nut rattle loose, but I do like to use lock washers. Weather, time, and temperature seems to bind the threads pretty well on it's own, even with using anti seize.

 

why shouldnt i use the red? and There arent any flange nuts. the heli coils are in the manifolds and bolts going through the clamp to them.

 

Red is a permanent locker, also makes it harder to get things back off if you need to. Blue is made to be used with 1/4"-3/4" bolts, red is for 3/8"-1" bolts.
I was saying nuts, not being sure if you were taking my stud instead of bolt recommendation.