I'm getting ready to buy parts for my all-motor build, and my friend told me it would be a good idea to replace my head stud. I found the some arp head stub for a decent price, but I also saw some that were called main stud. My question is what is the difference between head stud and main stud?

 

main studs are for your mains

 

His next question will be something like this " What are mains"...

Head Studs are used to fasten the head to the block/bottom end.
Main Studs are used to fasten the main caps down which hold your crank in place.

 

Thank you SD Lurker. Your info were much more helpful.