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Tighten head studs

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Hi all

Im assembling my long block soon and Im confused about head studs thighten

The manufactured recommendation is like that using bolts not studs with non MLS head gasket :

Step 1: Tighten 14 head bolts in several passes to the specified torque and in the correct sequence.

Torque: 400kg-cm 29 ft-lb 39Nm

Step 2: Tighten each bolt a further 90 degree in correct sequence

Step 3: Re-tighten each bolt and additional 90 degree

Questions :

1- Is this the right way to tight my head studs ? Or there is better way to do it ?

2- How to apply tight and loose technique in this case ? ( like the lesson tight it to 50 foot bound then loose it before tight it to 80 foot bound in 3 steps )

3- In step 3 it says re-tighten each bolt and additional 90 degree , is that mean loose it then tight it 29 foot bound with 90 degree and add extra 90 degree ?

Note : the engine is Toyota 1FZ-FE which is non turbocharged originally but we used to threw a huge turbo on it

Thanks

Mohammad Alajmi

The torque sequence and rating you've listed sounds like the recommendations for the factory bolts. This is what you'd use for a torque to yield fastener which isn't reusable. If you've moved to aftermarket studs then you'd use the factory torque sequence but you'd use the torque figures from the stud manufacturer.

Actually yes I have moved to an aftermarket studs but the problem is ARP doesn't offer Kit for my applecation so I used to oversized the threads to half inch then I get these studs AR5.000-lb1 which sold as single piece and it comes without instruction or torque recommondation sheet :(

thanks

Thanks got the right answer had misunderstand when contacted ARP then contacted them again and got the torque specs for these studs 110FTLBS

Glad you got a solution!