Very interesting answer

Re: re-torquing

Would you loosen them all the way and torque in three steps, or just check to see if each nut is still at the final torque from the initial installation?

 

I wouldn't be surprised if an important part of the puzzle was the thermostat. It would be interesting to know how many have been replaced with parts store thermostats (which list the correct one as 195) and then have head gasket failure.
The correct US thermostat is a 180.
There's also the issue of the factory temp gauge which don't properly register overheat so the drive may never know. As far as the driver knows, "It never overheated and now my head gaskets are bad!"

 

In all the rebuilds I did for the Cadillac motors, I never re-torqued the head with ARP studs. The heads are torqued in a cold state. The warm up will add growth to the dimensions and have an additive force on the stud/bolt. The sanding of the head gasket due to contraction/expansion is a very far stretch of the imagination. If you are concerned about the composition of the gasket being eroded away, then I would suggest you go to the Cometic gasket as I have been saying for several months.

Cometic is a properly designed gasket in regards to fire ring position, diameter, and construction. Yes it does cost more as well, which seems to be a concern to someone putting a thousand bucks of labor and parts into a rebuild. Go figure on common sense!!!

Some of this stuff is a joke I read. If you are concerned about coolant temp then buy the inline thermostat housing and drop in a 180 degree Chevrolet thermostat with a weep hole. Or machine the manifold to accept the Chevrolet thermostat and bolt on your elbow. How come all of the aluminum based engined from other manufactures don't have sanded head gaskets and failures from thermal expansion/contraction with a fiber gasket?? Hmmmm. Is that what is really causing blown head gaskets to begin with?

What is the tensile strength of the stock head bolt to be able to say they are the cause of failed head gaskets? I'd like you to provide an actual tensile test on the bolt (new and aftermarket) as reference to specs..

 

Right, over heating is a non-issue. What was I thinking?!

 

You were not thinking at all when posting just a snippet which confirms my position. Include all of the paragraph for accuracy.

"Some of this stuff is a joke I read. If you are concerned about coolant temp then buy the inline thermostat housing and drop in a 180 degree Chevrolet thermostat with a weep hole. Or machine the manifold to accept the Chevrolet thermostat and bolt on your elbow."

Thanks and have a nice day.

P.S. antichrist, I am not focused on you or picking on you. I'd be interested in you providing the tensile test of the aftermarket and OEM head bolt you refer to as solving the HG issue. I can do this if sent 2 bolts and record the results. Again, have a nice day.

 

I quoted the relevant part. You replied to my post about over heating being an issue by saying stuff you're reading is a joke, then go on to say if one thinks over heating is an issue, as if it isn't.
The rest you wrote, about a complicated alternative to just using the correct thermostat, is irrlevant.

Maybe you would. But since I never made any such claim you can do the tests if you want.

 

Here is some hard core math.
The verbiage is worth a read with respect to torque.


http://www.google.com/url?sa=t&rct=j...,d.cGE&cad=rja

 

I've been out of the country for a while, so I'm jst getting caught up on here but this is not quite correct. You must have missed some of the points discussed in materials class. The modulus of elasticity, or Young's Modulus, is a material specific coeffiient used in Hooke's Law to relate stress to strain within the straight-line potion of the stress-strain diagram. Once the stress exceeds the point where Hooke's Law no longer applies (the proportional limit) then the Modulus of Elasticity no longer comes into play. A bolt that stretches and permanently elongates has exceeded this point and is now on the plastic portion of the curve.

Anyway, when I'm ready to drop an extra $1,100 on the valve train of an engine that never revs past 5,000 rpm I'll be sure to contact you. Based on your responses throughout this thread I'm sure you are great to deal with from the customer side.