Is anyone running them in their truck or a pulling vehicle? I realize if you are that you are substantially into power and don't want to reveal secrets, but I'm just curious.

4x4

 

ok i'll bite ,,what in the world is a c ring your thinking of???! :-[

 

It is essentially an O-ring that has been hollowed out and when viewed from a side it looks like this: C. They are installed with the open end toward the combustion chamber; when your making over 100 PSI boost is when you start to consider them. In theory the more boost the more seal, as the head lifts off from boost the C-rings expand and keep contact to keep combustion sealed. You would almost have to lift the head completely off to break the seal.

4x4

 

I'm sure there are people out there that have C-rings installed. The idea is that the c-ring dynamically moves with the lift of the head which keep the extreme conbustion pressures from blowing the headgasket. Last test I heard using C-rings resulted in all the C-rings breaking and of course the headgasket blowing. Thats what led me down the path of using Big Fire Rings with grooves in the head and the block over the C-rings.

Horace

 

now i know why porsche head gaskets look so funny