Bolts Vs Studs

you must keep in mind that studs generally have two types of threads, one on the end that threads into the block,
and one end with a finer thread that uses a washer and nut assembly,
generally, if properly installed, studs allow the whole length of the lower course threaded stud to apply tension to the block,
so you get max retention strength, bolts apply marginally more stress to the first few course threads as they engage the blocks threads.
studs almost always have at least, potentially marginally more clamp force, but only if studs are properly installed.
studs must never be inserted into and tightened in the bolt hole threads until they bottom in the thread holes.
on applications like connecting rod bolts a stretch gauge rather than a torque wrench is used as the clamping forces are much more accurately measured that way

http://garage.grumpysperformance.com/index.php?threads/which-torque-wrench.342/#post-87029

Studs provide the ability to obtain much more accurate torque values because the studs don't twist or have added torsional stress applied during tightening as do bolts. Because the studs remain stationary during nut tightening, the studs stretch in one axis alone, providing much more even and accurate clamping forces.
but remember the finer threads, on the upper stud, the nut providing clamp forces on the threads onto ,
the stud will require a different torque value applied to provide the same clamp forces







as a general rule you insert and thread main cap studs into the block until the stud course thread bottom out on the shank or bottom of the block female threads then back out the stud at least 3/4 of a turn, back out, before you use them,
as the stud must not be bottom out on the shank or bottom of the block female threads while its under tension to function correctly
 
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if you've built enough suspensions you will eventually run across, some ones work where they used a common grade 5 or hardware store bolt where a grade 8 or stronger bolt should have been used, its amazing how often the difference in bolt strength becomes all to obvious as the lower quality hardware grade 5 bolts are far easier to bend or break.




yeah this is a repost,
Main studs

For a performance or heavy-duty application, the use of studs is preferred whenever possible instead of main cap bolts, in those instances where a choice is available. Studs provide the ability to obtain much more accurate torque values because the studs don’t twist during tightening as do bolts. Because the studs remain stationary during nut tightening, the studs stretch in one axis alone, providing much more even and accurate clamping forces. Also, because the use of studs results in less wear applied to the block’s threads, this extends the life of the threaded holes in the block over periods of servicing/rebuilding. This is especially important when dealing with alloy blocks. The use of studs also eases main cap installation, and contributes to main cap alignment. There is less chance of main cap walking because the studs remain stationary during cap clamping.



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