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Head bolt question

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  #1  
Old 01-16-2019 | 07:54 PM
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Default Head bolt question

I have taken apart my 02 se7 4.0 disco engine to replace my head gaskets and I'm now rebuilding. I have done the 15 ftlbs + 90° turn + 90° turn.

My question is this: does anyone know what the final ftlbs would be?

I believe that I saw online that its 90nm (wich translates to 66 ftlbs) I want to make sure they are all exactly the same torque,the 90° + 90° turns seems like there could be room for error. Can anyone lend their wisdom on this?
 
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Old 01-17-2019 | 10:29 AM
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Look up torque to angle or torque to yield head bolts on the forum or google. You did it correctly.
 
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Old 01-17-2019 | 12:25 PM
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I believe this is the problem with TTY bolts, if there was a final torque value, they would just give it you. I got tired of second guessing angles when doing head bolts and bought a fancy digital torque wrench that does angle calculation as well. I thought I was past angles when I started doing heads on newer models, but no. The new models use an angle sequence as well.
 
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Old 01-17-2019 | 12:53 PM
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Don't overthink it. Just accept the specified method. It works just fine.
 
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Old 01-17-2019 | 02:02 PM
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ARB head studs. 60 lbs. no angle, no stretch, no guess work. DONE!
 
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Old 01-17-2019 | 06:22 PM
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Thanks for all of your input folks, helps put my mind at ease.
 
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Old 01-17-2019 | 06:29 PM
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Is there a good time during the rebuild process to check compression? I just got the rocker arms on this evening and wondering if at some point I should or could test for proper compression before I get it all back together, hate to over look that until it's back together and have to go back in there. Low compression and a coolant leak led me to rebuild
 
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Old 01-17-2019 | 06:59 PM
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Right now would be good, since you have the heads and the valve train installed but haven't installed the intake. If the alternator, PS pump and A/C are not yet installed that's okay. You don't need the serp belt installed to do a compression test. You may want to set the valve covers in place without torquing them down. Just put a couple valve cover bolts in place and tighten them lightly. No need to torque them now, and you don't need to install the valve cover gaskets yet.
 
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Old 01-17-2019 | 07:38 PM
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Originally Posted by mln01
Right now would be good, since you have the heads and the valve train installed but haven't installed the intake. If the alternator, PS pump and A/C are not yet installed that's okay. You don't need the serp belt installed to do a compression test. You may want to set the valve covers in place without torquing them down. Just put a couple valve cover bolts in place and tighten them lightly. No need to torque them now, and you don't need to install the valve cover gaskets yet.

thanks for the help!
 
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Old 01-17-2019 | 08:17 PM
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Originally Posted by abran
I believe this is the problem with TTY bolts, if there was a final torque value, they would just give it you. I got tired of second guessing angles when doing head bolts and bought a fancy digital torque wrench that does angle calculation as well. I thought I was past angles when I started doing heads on newer models, but no. The new models use an angle sequence as well.
It's actually the opposite. TTY bolts are a new thing that older vehicles don't have. Manufacturers found that they hold better over longer periods, and it's easier to get a consistent torque across the head because you actually pass the bolts yield point , meaning the bolt reaches maximum torque before final rotation, and all the bolts yield at the same point.
 


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