Head bolt torque

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So I have the new head assembled, and painted, the block verified flat, and now I see that the Cummins gasket set says to torque to an angle torque, but the factory manual (Dodge supplement for the Cummins engine equipped truck) has no such spec. What gives on the head bolt torqueing? Anyone have or know where the info is? Do ya have to angle torque these bolts or is just torqueing enough. TIA

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Bill Red 90 4x4 5 spd, 4. 10s, banks stinger, K&N, Racor remote filter

 

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As I posted the last time, I torqued the bolts to 110-120 ft lb instead of +90 degrees because the latter seems too variable, at least with the used bolts. The Dodge manual says torque the long ones that hold rockers down to 89 ft lb and the others to 66. Then turn every bolt an additional 90 degrees.

 

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I recently had a rocker off a '97 engine. I was very surprised to find that the long head bolt loosened with very little force. The ones next to it felt the same. I agree with Joe, here. The used bolt did not give me the same "stretch" feeling you get with a new one. It just got dramatically tighter with little further movement. The specs are, of course, for a new gasket. My guess is, that the gasket crushes a bit, and the real tension against it comes down.

I didn't give them the 90 degree turn because of it. Also, I just couldn't pull that hard while laying across the raised, winch-and-extended-grill-guard equipped front end. Like Joe, I set the torque wrench up a bit. Hope it doesn't cause any problems in the future.

 

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Maybe I should have explained a bit more. AFter taking the olts to 66 and 89 ft lb per the manual, I tried the 90 degree additional turning. I found that I got to 120 with some at maybe 45-60 deg turn and others weren't up to 120 even at a bit over 90 deg. It was apparent that some bolts stretched more easily than others. However, I was able to get all to 120 without any of them feeling like they were stretching too much (i. e. needing replacement). Since I felt the goal was even clamping, I decided that 120 ft lb all around was better than the 90 degree where some would be way over 120 and others at about 100+.

 

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I'd agree with you on that one. I've had other engines with bolts yer supposed to stretch, and it sure seemed to me that some of them had a lot of 'give' and some didn't. Perhaps some of them are hardened a bit too much and therefore don't give, and others aren't quite enough, and give too easily?


I'd hate to think all those engines are assembled with such variability in fasteners. Maybe it's some other factor entirely.