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A1 1722 head studs, bottom tap needed?

2K views 9 replies 6 participants last post by  Chevokeeman 
#1 ·
Do a1 1722 need to have the block bottom tapped?
 
#2 ·
Need....NO. Recommended...YES.
I've yet to bottom tap any truck and never had a problem.
 
#3 ·
I'm thinking a year or two back a guy from southern WV bottom tapped his block and hit water. :confused013: :shock:
 
#4 ·
Short answer is no, that's why the bottom 1/8" is not threaded, so it will go past the partially cut bottom threads. I believe you are thinking of the H-11 Studs, which do have more threads and have to have a bottom tap run to get the extra thread contact.
 
#6 ·
im sorry im a newb to diesels but how much of a gain do ppl see from head studs? any? Y should I do it? sorry just wondering. Thanks for any reply
 
#8 ·
The gains you get are hopefully less chances of lifting the head and popping the gasket out.
 
#10 ·
Download the instructions off the Glacier Diesel site for ARP 425's and follow that, but make the final Torque 115 ft. lb's, I bumped mine up 10 lb.'s to 125 lb/ft and haven't had any problems.
 
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