Ok so when i get on it hard pulling a decent load uphill with boost at 35-40 and pyro at 1000-1100 i am puking coolant due to blown head gasket. I was towing with 18 degrees of timing and I thats just to much i figure. So its set at 15 now.

Now for the question:

My o-rings are ten thousands I have heard that this is great for contact pressure but it is in such a small area that it can be bad.

Should in get shorter rings and if so what size.

I had 40,000 on the last head gasket so I figure the higher timing and the towing must have done it. anything would be helpful right now I don't wanna do the head gasket with those rings if they are not optimal for my application and I really am over the beating the tar out of my pickup just goin for reliable

Hows it go again FAST CHEAP RELIABLE pick any two right

 

im not sure but im wanting to learn also. because im running the same and worry every time i start the rig

 

From what I hear four thousandths is good but we'll see

 

Mine are at eight. Retorque on the head studs after heat cycles are important when running o rings.

 

i forgot what size o-rings i got but i torqued my head studs to 150 ft-lbs cold then hot then did it about 4 more times

 

Most of the time the o ring consists of a .041 stainless steel wire which is installed into a .030 groove in the head. That leaves .011 potrusion, this works well in gasoline race engines because they normally use copper head gaskets with o rings. Since cummins gaskets have a hard solid fire ring I had my machine shop only leave .008 potrusion. I torqued my ARP studs to 140psi 4 heat cycles. I also spray the gasket with copper coat to help seal the water.

Derek