OK I threaded out the hole for a bigger hole of 1/2" I have it torqued down and is holding fine. Sucks that I had to do that but I wasn't about to spend tons on the motor just to have to it blow one day. I plan to do a 408 build later but not know

 

I think my concern with this application is that GM put the threads deep for two reasons (at least this is what I think). One is to pull on a stronger/thicker block section and second to allow for longer bolt length and therefore stretch in the bolt to pre-load the gasket.

 

The torque value will be different if you are using a bolt. If studs, it will be different if the thread where the nut is located has changed. You should verify so that head clamping load is consistent.

 

I can see your point but ...
It doesn't take to much to strip the threads in these aluminum blocks.

If you can install an insert in there and get the bolt tight with the correct amount of torque, I think it would be ok.

Hearing these stories about stripped block head threads is kind of un-nerving to me.

If I was going to remove my heads more than once, I would consider ARP head studs. I might consider those anyways because I'm about to do a head/cam swap, eventhough it's only my first time on this motor.






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I went with studs because I like the fact that the studs go in by hand and then when the head goes on you are pulling on all the threads in the block rather than turning against the threads. Aluminum threads are fragile to start with and fixing a block thread would be a beeaaacch.

 

I dunno i dont think its a design problem, i think one of the major reasons people strip out head bolt holes because they dont get all of the coolant out of the holes. You cant compress a liquid and when you try to torque it down, bye bye threads. If you install properly(no water in the bolt holes and lubed threads) you should never have a problem with stripping the head bolt holes. Think of it this way, when you install the head bolt and torque it down the bolt stretches while the entire bolt still spins and moves down in the threads. When you try to torque it down with any bit of coolant in there the bolt will not be able to move any further down the threads because it cant compress the water underneath, it will still spin though and thats when the threads go.

I know when i reinstalled my heads i was very cautious to get every drop of coolant out of the block by using compressed air with a small silicone hose and stuck it to the bottom of the holes in the block. then i went through and put rolled up paper towels in each hole to absorb anything that was left. didnt have any problems. If you do have water in a hole you can usually feel the bolt get "spongy" before its too late.

I know there are other reasons head bolt threads could strip but if your cautious and do everything by the book i would think it would be fine for atleast a few installs. But studs are always a good option, just expensive.

 

Hey guys this has been the appropriate thread about stripped block threads at the right time. ( oops I did a pun ). I basically have all my parts together, getting ready to do the head/cam/oil-pump/timing-chain swap.

Since I have new GM head bolts allready , I'll go with those. Cleaning the bolt holes correctly and completely coolant, water fee sounds like real good idea.
This will be the first time installing new heads on this motor, so the GM head bolts should be ok.

I found this to be a good read... I liked the pretty pictures too.
( You guys most likely know about this anyways ).
http://ls1howto.com/index.php?article=2
http://ls1howto.com/index.php?category=0



Questions:

About the ARP head studs... being that those are put into the block by hand...will those stay in the block when you go to remove the heads a second or third time ? Do the ARP nuts come off of the head studs easily ?
Is there ever times when the nut gets stuck on the head stud itself ?



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The Arp head studs come with a moly grease that's suppose secure the studs in the block so unless you damage the threads above the nut it shouldn't remove the stud hopefully, but it shouldnt matter if does or doesn't its not like you can't thread them back in. I never have had to remove my heads since I put them in so I dont know.

As to why did the head bolts stripped, I work on Toyota's for a living and almost almost always when one of our customers decide to drive the motor without coolant and cook the engine, it pulls the threads out when the head warps.

 

If someone wants to spend the extra $225.00 for ARP head studs, it sounds like a good peace of mind.

It's hard to think that head bolts will strip themselves.
Apparently aluminum is more prone when precautions are not taken.

I never really hear stories about stripped threads on steel blocks.

You mean the mighT-y mighT-y toyota actually gets stripped threads. lol


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Great advice above.