Torque to yield bolts?
#1
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Torque to yield bolts?
I have tried a search, not a NooB.
I need a complete list of what bolts are re-usable if removed for a re-build.
Headbolts- junk when removed
Main bolts- ?
Rod bolts- ?
etc.
etc.
I need a complete list of what bolts are re-usable if removed for a re-build.
Headbolts- junk when removed
Main bolts- ?
Rod bolts- ?
etc.
etc.
#4
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Any TTY bolt needs replaced as it is only used once, because when you torque it you are stretching it. Not sure what year block you have but I have a brand new set of GM head bolts(short style) for the older blocks ill give you a good deal on. I had to buy the ARPs because my block takes the long style. Let me know...
#5
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TTY are okay to re use if they were torqued properly before and didn't surpass their yield point, meaning they returned to original length when broken loose. If they were torqued (stretched) past their yield, then they are pretty much junk and won't provide adequate clamping force.
Everyone says not to re use TTY because you really can't tell if they are good or not. I don't think new TTY bolts are all that expensive for the peace of mind.
FYI: Stock main bolts come on all brand new blocks from GM so find a machine shop that specializes in LSx engines and you may get a good deal (ie free).
Everyone says not to re use TTY because you really can't tell if they are good or not. I don't think new TTY bolts are all that expensive for the peace of mind.
FYI: Stock main bolts come on all brand new blocks from GM so find a machine shop that specializes in LSx engines and you may get a good deal (ie free).
#6
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ANY bolt would be OK to re-use if it were not torqued past the yield point... However, torque-to-yield are not torque-to-just-before-yield-then-stop (or, in other words a "normal" bolt) they are torque-to-(past)-yield. This means that all TTY are stretched past the yield point. The torque specs get you to the bolt yield point, the additional degrees of turn will determine the stretch of the bolt, they are torque-to-just-before-yield and then stretched to far beyond the point of reuse...
DO NOT REUSE TORQUE-TO-YIELD BOLTS!!!!!
#7
TECH Senior Member
I would change head bolts, main, rod, crankshaft, also be aware that main caps should be reinstalled exactly in the same place they cam from and are not interchangeable from another motor