New head bolts

road_king

road_king

Member
I'm getting ready to put a new high compression head and gasket on. I decided while I'm at it to put new moly head bolts in. I know the torque specs and re-torque parameters for the head nuts after the head is installed, but what about the bolts themselves. When I install the bolts do they need to be torqued or hand tight? Also should I add anti seize or other thread compound to them? Thanks
 
Here is what I do. I apply anti seize on the coarse thread end that screws into the block and none on the fine threads where the head nuts go. I just bottom the studs with slip joint pliers, no torque needed on the studs. If you have a Brattons catalog, the head nut tightening sequence is pictured on page 38 in the left lower corner of the page. Tightening sequence is important and I do this in three stages. Snug the nuts up. I usually first torque in sequence at about 15 ft. lbs. then 35 and then 55 ft. lbs. I crank and run the engine for about 20 minutes and re torque while still hot and before it springs any leaks. Usually you will be lucky if it is still holding 35 or 40 ft. lbs. torque.. after the first torque and crank up. It will need to be rechecked in a few days and re torqued in sequence again. If you are using grade 8 studs and nuts you probably can get by with two or three re torques before it holds torque. If grade 5 studs and nuts are used it may take 5 or more re torqueings before it holds. I believe that 55 Ft. lbs. is plenty, any more runs the risk of damage to the eighty year old block threads. On the last one that I did, I didn't use a gasket under the upper water neck.I applied a THIN coat of clear RTV to the mating surface of the head and tightened the water neck in sequence at 55 ft. lbs. torque. Some will disagree about the first torque while hot but this procedure has worked well for me. All other torqueings should be done while cold. If the head is aluminum, this may not apply and I would seek the manifacturers instructions.
 
Hi Road King,
One more thing, the stud height is important. If your head is the same thickness as an original head these are the stud heights. All studs except #8, #11 and #13 should extend 2-3/4" above the block. No's 11 and 13 should extend 5" above the block and #8 should extend 2-29/32 for the ignition cable.
 
Al 29Tudor said:
Hi Road King,
One more thing, the stud height is important. If your head is the same thickness as an original head these are the stud heights. All studs except #8, #11 and #13 should extend 2-3/4" above the block. No's 11 and 13 should extend 5" above the block and #8 should extend 2-29/32 for the ignition cable.
Click to expand...

Ah yes, forgot about those spec's... thanks guys..
 
I also apply copper anti-seize to the non threaded shaft of the bolt. It makes for much easier head removal in the future.
 
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