I have used the blue loctite stuff on my caliper bolts when doing front/back brake pad changes. The originals already had some orange paste on them!!!!!!!!!!!!!

i'd love to watch someone trying to crack some loctited head bolts once they are 100k+ old lol

if you're head bolts are coming loose you are doing something wrong...
having had to grind/cut out rounded bolts in the past, once the pressure on the face of the bolt is released the bolt can be undone easily with only fingers.

anything supplied with the bolts would be only to assist with the bolt being done up with the correct resistance, not attempting to weld the bolt thread into the block.

there are quite alot of bolts throughout the car that should be hit with loctite, but not head bolts.

I gather it's actually sealant that's called up - I made the usual assumption that "Locktite" meant thread locking compound but of course Locktite make all sorts of things.

Using a standard duty locking compound would not make removing the bolts all that much more difficult than normal - I undo fasteners every day that are secured with thread locking compound (including large bolts - ie. 1/2" 9/16" ) and have no problem. The compounds we use are 243 or 246 - it's also oil resistant so doubles as a sealant...

Using something like super stud locker might be a bad idea.

A sealant on these headbolts I should imagine would be mainly to keep water from getting in and rusting them - ie. if a headgasket problem allows water to reach headbolt holes.

The loose bolts I've found have been on FACTORY fitted first time heads - none of the ones I've done up have ever come loose - but no to date I've never used locking compound myself on them either.

I work in a truck work shop, we dont even use loctite on head bolts on the big trucks like kenworths. Theres no need for loctite if the bolts are torqued correctly, its that simple.

I've never used locktite on headbolts either...

My comments have been in the context of it being called up for I6 ones (tho evidently it's sealant they're calling up) - but if someone did happen to use 243 or 246 it wouldn't be a disaster.

Yes well, my book called for locktite 246. We didn't have any, and what came with my headbolts was a satchet, but im pretty sure it was only a lubericant now. But I gave them a oil anyway and its all said and done now and im left with a dry, running car. But for how long...haha. Im sure I stuffed something up and it'll show itself soon enough.

246 is actually a medium strength, high temp thread locking compound - but don't panic about not putting the Locktite on - as others have said, they will be fine without it as long as you torqued them properly - especially as you've used a little oil (they seem to be done dry from the factory in ED and EF's at least!).

Yea my mates ef headbolts came out rusted...
Mine came out oiled still tho.
Also my car has struggled to get to 70kph in 2nd since I got it. Today she hit 80 no worries and was only at 4000rpm.!!!
Loven it!