Had an Awful Scare - PD Cam Hub Bolt Torque?

About two weeks ago I rebuilt my engine. I've driven it 1000km since then and it has been running perfectly. (This is the 2004 PD by the way, not the 2015, as you may have guessed)

I was following a break-in procedure, so I hadn't given it full throttle or revved to redline in all that time.

Well today I decided to wind it out for a second. After all, it has been 1000km, so most of the break in is done.

It made an odd sound and basically lost all power! It was then idling, but I was stuck behind a bus, so I had to stop the car. When I tried to get moving, it stalled, and wouldn't restart.

I got it towed to a place where I could work on it and it turned out that the three bolts that hold the cam sprocket to the cam hub had allowed the cam sprocket to slip to the end of the slotted holes. The bolts were still tight.

I reset the cam timing (used VCDS and everything) and the car fired right up like nothing happened. Sounded fine. I did a compression test and all cylinders were the same, about 410 PSI. I would say no actual damage was done. I drove home and it was fine.

Keep in mind I have a Malone Stage 4 tune, so full throttle is serious business on this thing. I'm sure there is a huge amount of stress on the timing belt and cam sprocket since the cam is operating the injectors. The more fuel you inject, I assume the more strain there is on everything.

Just how tight are those three bolts supposed to be? I admit I didn't look up the torque spec, but I just made them about as tight as I dared using a 1/4" drive ratchet. You know that feeling where you're like "Okay, these are small bolts, if I go any tighter I'm sure they'll break?" That's how tight I made them.

Is this common? Should I be worried that there's more going on? I guess I'll be wanting to torque those to the correct spec, and Loctite them so they don't loosen or anything.

I have since found that those bolts are supposed to be tightened to 25Nm (about 18 ft-lbs) so I’ll give that a try and hopefully they don’t slip.

It will sure be embarrassing if the car dies every time I try to pass a mini-van that wants to race ahead, get in the way, and slow down, as mini-vans do.

I personally would replace those bolts just to be safe. And make sure they are properly torqued every time. Some things you can torque by feel but a moving engine part isn't one of them.

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I tightened them to 20 ft-lbs and found that to be a little more than what I had done with my little 1/4" drive ratchet. (I tightened them with the small ratchet, and then further tightened them with the torque wrench and they turned maybe another 70 degrees).

Hopefully all that was wrong is the bolts weren't tight enough. I thought I had destroyed my engine....again!