[V8s_are_slow]

1st, does anyone know if a Cometic HP headgasket is reusable?

2nd, anyone know torque specs on Arp head, main, and rod bolts WITHOUT the molylube? Having to check for any spun bearings, etc. so Taking it all apart. Thanks!

Scott

 

[Stephen]

I do not believe the cometic headgasket is re-usable. I do know from personal experience the mitsu metal IS re-usable. I believe the fasteners without lube should use oil as lubricant and are about 10ftlbs tighter.

 

[V8s_are_slow]

What weight oil?

 

[Asmodeus]

I've seen one used 4 times now.
cometic

Due to problems it had to come apart a few times in the early stages.
Its now seeing 28+psi from a 60-1.

Without a hiccup.


use straight 30w or higher.
I went to 110 then on the retighten 115 on the head bolts.
in 10lb increments from 40lbs
in sequence.
(using mitsu 4 layer)
not the slightest problem yet.
(I didn't have lube either.)

MAN were my arms tired.

 

[K_Mans_TSI]

torque specs are signifcantly higher with just oil....i know they recommend 80 with the lube and over 100 without...that's for normal values, most guys will torque closer to 100 with the lube on larger turbo applications i have no idea what that would be without lube.

 

[4SFED4]

I use moly lube and torque to 85 ft/lbs in 20 lb increments.
2nd I start the engine and let it run to operating temperature low RPMs(<3K) no driving/load.
The I let it cool to the touch, loosen the each fastner a 1/4 turn individually and retorque it to 85 ft/lbs in the proper sequence.

I have used that method on Cometic, Mitsu 4 layer and SCE copper gaskets. I have tried to torque the cylinder head as high as 120 ft/lbs(same method/procedure) and it makes no differance.
When the engine reaches its threshold of boost and timing the head will lift. With conservative timing I have had no problems with any of the above gaskets. I even drove on an almost daily basis with a SCE plain Copper only using Permatex copper coat to seal, no coolant seepage or loss.