PUTTING ENGINE BACK TOGETHER AND HAVE STRETCHED A ROD BOLT. WHAT IS THE SPEC ON ROD BOLTS TORQUE?

ALSO SOMEONE SAID I NEED TO HAVE THE RODS ALL PULLED AND INSPECTED SINCE I AM GOING TO REPLACE ALL THE ROD BOLTS? IS THIS TRUE?

DON'T SEE THE POINT IN THE ROD'S INSPECTION IF I AM JUST GOING TO REPLACE ONLY THE BOLTS.
Original Post
If you are reassembling your engine and people suggest you inspect your rods it is mainly to see if where they connect are still within spec. Over time they made need to go .010 over or so.... Also anytime you have the rods out or have loosened them up it is a better idea to replace with new Grade 8 or higher like ARP. You see a bolt, when initially tightened, will perform to spec. However when you loosen and subsequently retighten it is weaker then before. Regardless of how minute the change may be but the constant tightening and loosening of bolts weakens them inherently... Take a rod bolt. It has a raised area along the top of the shaft under the football head designed to be pressed into the rod. When the bolt is removed - the form fitting metal which served to secure the bolt doesn't "magically bounce back"...

Trust me the security with replacing your bolts far outways any agrument for not doing it...

Dave
Bolt torque is 40-45 ft-lbs for regular rods and 45-50 for Boss 351 rods. There are two different bolts used- the so-called 'football-head' bolts are regular 351C. The sorta-squarish bolt heads are the Boss units. They interchange in any rod. But the difference in torques isn't enough to stretch a bolt- someone at some time REALLY leaned on the wrenches! I would replace all the bolts with Boss bolts- Ford still sells them as does the aftermarket. Likely the rods are OK.
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