thread pitch/bolt size

[danz503]

first post here. a 1990 jeep 4.0 block has 7/16" coarse thread for head bolts .437 diameter. the head i want to use "7120" casting # has bolt hole diameter of .530". that seems like a lot of air between the two. wouldn't this allow the head to float/move? anyone have a fix for this or am i just overly concerned? any help will be appreciated.

 

[jeepinmatt]

first post here. a 1990 jeep 4.0 block has 7/16" coarse thread for head bolts .437 diameter. the head i want to use "7120" casting # has bolt hole diameter of .530". that seems like a lot of air between the two. wouldn't this allow the head to float/move? anyone have a fix for this or am i just overly concerned? any help will be appreciated.

It'll be fine. There's dowels to keep it lined up. Whether it's 1 thou of clearance or 100 thou, it's still clearance. As long as there's enough bearing surface for the bolt head, it'll squeeze on down.

 

[Jeff B]

I have a 7120 on my 99 4.7 stroker. 7/16 head bolts no issues.