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I noticed that the inner most head bolts were noticeable looser than the outer head bolts, despite a torque, and a re-tourque 300 miles later.


if you can find some nuts that fit your head bolts, you may want to put them on, thread them up to the top of the threads. If you have a die, put that on next, then grind the last couple threads off to shorten the bolt a bit.We used to do this on VW motors that we cut down for compression. Then run the die off, and then the nuts. That should give you clean threads, and hopefully alleviate the possibility that the head bolts are bottoming out before they get to full torque. It might help