ALH Head Bolt Dimensions?

[The Shootist]

Can someone tell me the size, thread pitch, and length of the head bolts on and ALH engine?

After the ARP Head Stud thread I would like to try a "Non-Stretch" head bolt to see if it makes any difference.

 

[tdi'd]

Did you ever get the answer to this question?

 

[ToxicDoc]

he hasn't been on the site in over 2 years...

 

[Mongler98]

why anyone would need to know this info is beyond me! it's pointless. either you go with stock one time use bolts and follow the install specs, OR you have a block built out to handel ARP studs. installing them to "fix a head gasket issue is a band aid that really can do more harm than good.
you can not use ARPs on a non prepped block and head if you want things to last.

 

[[486]]

may as well throw the pertinent info here because google obviously brings this thread up when looking for head bolts
better than just a bunch of dickering about post dates

m12x1.75
length is something like 110mm iirc, don't have one to measure ATM, they're out in the cold dark garage
length of the bolt boss in the head is 80mm, counterbore in block is 10mm deep, and 20mm of thread engagement feels proper

iirc there's a part number floating around for 12.9 head bolts from a PD application that you cut down for ALH, I don't remember the part number.
I'm the special brand of idiot that gets away with reusing stock tty bolts from time to time. My current daily has some reused rod bolts in it.

you can not use ARPs on a non prepped block and head if you want things to last.

what do you do, wave a magic wand at it?

 

[Poor King]

why anyone would need to know this info is beyond me! it's pointless. either you go with stock one time use bolts and follow the install specs, OR you have a block built out to handel ARP studs. installing them to "fix a head gasket issue is a band aid that really can do more harm than good.
you can not use ARPs on a non prepped block and head if you want things to last.

Should I not use ARP headbolts if I rebuild the full motor to stock however upgrade to an 11mm pump, higher flowing injectors and an rc3 tune with a vnt-15?

 

[Mongler98]

Only if you have the block bored and honed with them installed with a pressure plate. That or risk a cracked block and slpiston sidewall scaring.