Stupid Studs...

well here is my debate. if i am going to drill and retap all of the holes, why not just drill and retap for some 14mm studs?
500 bucks more for new studs, but i can sell my old 12mm ones and the amount of money i spent on helicoils compared to the total after everything for 14mm studs is minimal, right?
 
cummins freak said:
so what your saying is when a person goes to install head studs they don't need to bottom tap because the studs will go deeper anyways??? what about cleaning out the original threads
You don't need to clean up the threads. Just take the bolt out and screw in the stud. You may have some oil in some of the holes that gives some resistance but by turning slowly with the hex key they will go in. You have to careful when chasing threads in cast iron not to cut the top off the threads.
 
joefarmer said:
When a prostock team gets a new block what's the first thing they do with it? They heli-coil all the head stud holes. Heli-coil + stock block material will hold more clamping force than the original block material because of the larger heli-coil thread engagement.

brandon.

None of the Pro stock blocks I have been involved with. I provided the DRCE II and III to the shop that did 99 % of all Pro Stock blocks out there for many years .

I would not have a problem fixing a few holes with heli coils, but the block is always better. My 8.72 Cummins had heli coils in two main studs holes, and the caps were retained with out walk, the 53 part of the block gave way.

This rush to 14 mm studs is not the way to go, the Cummins block is a limber block, and the amount of material removed in the deck surface, and head is detrimental to the integrity of the block

With the plentiful supply of good quality studs like the ARP 2000. The clamping force required to contain combustion is readily available. If you having problems with head gaskets you need to look else where then the studs.



First common problem. O ring protrusion all over the map on the same head. From .008 to .018, culprit, the BHJ Tool, it was designed for using an o ring on one side of a dead soft copper head gasket, and a mirror receiver grove on the other side. The close tolerances need for what diesel people call an o ring , and really is a retention ring , needs to be dead on , .008 for street , and .010 for race.

Second the machined surface needs to be flat, again all over the map the Cummins 24 valve is again like the block, very movable.

Third tune up.
If you need more clamping force, then Doug Smith or myself have the answer new age 625 12 mm head studs. This is over kill for most, and able to achieve clamping force equal to the 14 mm . . With the plentiful supply of good quality studs like the ARP 2000. The clamping force required to contain combustion is readily available. If you having problems with head gaskets you need to look else where then the studs.
 
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COMP461 said:
First common problem. O ring protrusion all over the map on the same head. From .008 to .018, culprit, the BHJ Tool, it was designed for using an o ring on one side of a dead soft copper head gasket, and a mirror receiver grove on the other side. The close tolerances need for what diesel people call an o ring , and really is a retention ring , needs to be dead on , .008 for street , and .010 for race.

Second the machined surface needs to be flat, again all over the map the Cummins 24 valve is again like the block, very movable.

Third tune up.
If you need more clamping force, then Doug Smith or myself have the answer new age 625 12 mm head studs. This is over kill for most, and able to achieve clamping force equal to the 14 mm . . With the plentiful supply of good quality studs like the ARP 2000. The clamping force required to contain combustion is readily available. If you having problems with head gaskets you need to look else where then the studs.

This is why people just need to stick to the thread.

1st oring protrusion is fine.
2nd machined surface is flat
3rd He is not having headgasket problems He simply pulled the threads out of the block. While trying to install new head.
 
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Thanks for getting us back on track Chuck... So is helicoil the way to go then?
 
COMP461 said:
None of the Pro stock blocks I have been involved with. I provided the DRCE II and III to the shop that did 99 % of all Pro Stock blocks out there for many years .

I am going to go out on a limb, and guess he was talking about pro stock tractor motors, which is a whole new level, compared to what you have dealt with.
 
so someone give me an exact brand / website of what they are using for heli-coils.
in my past experience with them, they dont seem to hold too great so i am VERY hesitant to just go out and order 26 heli-coils and have them not work and be out a couple days work
 
I have heli-coil some hydrolic diffs before, and never had a problem with 5600psi held pretty good and probabbly still in service.
 
helicoils are ok to use... but it has to be a good set. some are straight screw ins. some you brake off the tab. others, you screw in then use a tool that stakes down four lil tangs that holds it in permenitely. we used these a lot at caterpillar. worked outstanding. the best but do cost some since not all kits come with the staking tool. hope this helps.
 
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