Put headers on the 440. Cyl 5 and 6. Has bolts. Rest are studs. The bolts go into water jackets right? Pipe tape or something else?

i always use Permatex Ultra Copper on anything that will get hot.
i don't think pipe tape would be a good choice on something that get as hot as an exhaust bolt.

Hylomar or liquid teflon pipe thread sealant.

I believe all OE iron BB head ex bolt holes are wet. What about using OE shouldered double male studs in em as they do seal very well (with some cement). You can trim the outer fine threaded end to where just enough thread length is left to where with the header/gasket/nut installed/torqued, the nut fits flush on the thread end (grab your tape). trim as needed before installation. when done, any threads protruding past flush with the nut is a waste & greatly hampers header fitment, either flange going over the bolt and or bolt thread interference with header tube. & there are thinner high grade nuts for further clearance help

I use studs even on my aluminum heads.Only place I use a bolt is where studs dont work.IIRC Its one.When i ran bolts i use silver anti sieze and went years with no leaks.That and they come right out after years of running.Rocky

If this is a new install, make sure you can get your headers off the studs. Someday you may want to remove them with the least hassle...

Although I suppose there is plenty of room in an E-body. Not so in my A-body

One of the many benefits of alum. heads...

Stock motor. All are studs but just them 2 cyl. So will have to have a bolt. Just wanting to know if the Teflon tape will hold up and keep it sealed

I always used some high temp rtv? Seemed to work back in the day. I think the tape would work. Where can it go? Even if it gets hot it's not going to flame out and disintegrate. It's stuck between the threads right?

This ^^ I use Ultra Copper RTV, it handles the heat and I coat the the whole bottom of the bolt/stud so it stops corrosion of the bolt that is in the water.

Thanks guys. That's all I needed to know

Teflon paste. Works better than RTV over y he long haul.
Doug

i use loctite 567 [part# 56765] teflon sealant on almost everything. it has a high temp rating also. works great on stainless fittings galling problems too.

^this^ I ain't used it (yet) but as said it is (been) highly recommended by many people

I always use red RTV for that.