: studs for block

03-12-10, 11:14 AM
do ARP studs thread into the stock holes in block? or do you have to insert the block to repair damaged threads if you plan on using these studs? most folks say removing the headbolts results in damaged threads in block. what is the preferred method to use ARP studs?

03-12-10, 11:51 AM
Studs require that the block head bolt holes be align-bored and tapped to accept larger diameter threads than stock. The idea is to get the studs into new block "meat".

Replacing stock GM head bolts with same-sized studs accomplishes exactly nothing - and GM recommends that any head bolt hole which appears damaged must be inserted. The tried and true fix for Northstar failed head bolt threads (all 20 holes) is inserts or Jake's studs, with studs being the strongest fix.

03-12-10, 12:04 PM
ok, i found the info online. ARP studs are the same thread diameter on both ends. studs are also used on some VW motors. so if you have damaged block threads you need to insert the block before you use these studs since they are not oversize thread like on jakes kit. or drill and tap the block threads oversize and than use jakes studs without inserts.

03-13-10, 10:44 AM
dont make things dificult just call up Northstar performance and buy a set of studs... why try and re work something that has been perfected?

03-14-10, 04:32 PM
who would use the ARP studs? someone with an undamaged block threads?

03-14-10, 05:28 PM
FWIW, I use ARP studs in iron block Olds 455's - bulletproof. Given the bolt thread problems with aluminum (particularly late 90's Northstar) blocks I would machine all head bolt holes and install oversized block thread waisted studs without hesitating.

For another take on head studs vs. bolts, go to the ARP catalog (Google "arp bolts") and look at P.36. (Also note that P.37 lists no studs for Northstars), so for the cat's meow in Northstar engine top end strength Jake is the only act in town.

03-15-10, 10:21 AM
the ARP tech said the studs are spec'd for VW motors but just happen to work on a northstar. except the block will probably have thread damage if you use it as is. so you drill/tap the holes oversize and have to go with different studs. wonder why ARP does not make waisted studs for the northstar? i wonder how many stud kits they sell for the VW application?

03-15-10, 01:59 PM
Probably a fair amount for the VW's. Probably not enough demand for Northstar studs from a performance-oriented manufacturer like ARP.