Replacing/Sourcing Head Bolts for '79 Spider

[So Cal Mark]

the advantage to a stud is where the pressure is applied. A bolt will pull against the threads in the block, ever so slightly distorting the block surface. With a stud, the pressure is on the nut on top so that not only do you get the force applied in the best location, you don't distort the block.
If you don't believe me, ask any machinist why they use block plates to bore and hone cylinders. Head bolts distort the block when they are torqued, studs prevent this

[majicwrench]

Studs pull on the block thread just like bolts. Studs do, however, provide a better clamping force. That must be why all the manufacturers use.........um, well, most of em use bolts. Even Subaru (since somebody mentioned Subaru) went from studs, to bolts. Hmmmm

I'm not saying there is anything wrong w studs. Simply saying that there is no need to throw out head bolts that are in good shape. Comparing a toque-to-yield bolt to a regular head bolts is like comparing a paper towel to a dish rag. One of em is designed to be used only once.

[chrisfiat]

$$

[chrisfiat]

Studs pull on the block thread just like bolts. Studs do, however, provide a better clamping force. That must be why all the manufacturers use.........um, well, most of em use bolts. Even Subaru (since somebody mentioned Subaru) went from studs, to bolts. Hmmmm

.

take an engine and install the head with bolts, and then do it again with studs, now think about mass manufacturing, and you will get the idea of why manufactures use bolts. it's all about the $

[So Cal Mark]

not something I made up, it's proven that studs don't distort the block like bolts do

[majicwrench]

I don't recall saying you made it up.