Ok, won't be long now I'm gonna get into a new turbo. Either a decent sized single or some towing twins. What I need to know it this. What exactly does it mean to fire ring a head? What PSI do you need to be capable of making before you need this mod? Also what kind of PSI range do you need to start considering head studs and what all's involved in doin that?

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bump, nobody has any input on this? I figured I'd have all kinds of responses to this?

 

Anything past 35 lbs really is a necessity for head studs. Fire ringing a head means they machine a circled groove into the block and place a rubber ring into it. It's suppose to prevent the head gasket from blowing out from excessive boost, just like head studs are to prevent bolt stretch. To do head studs is simple, but labor intensive. Have to do 1 at a time if you don't plan on an o-ring job. Run a tap into the hole, then thread the stud into place.

 

"Fire-ringing" a head means that you bought a headgasket from a place like Haisley's that is modified with a bigger firering than stock; the larger firering requires either the head, block or both to be cut around the top edge of the cylinder. This is supposedly better for a bit more boost pressure than O-rings, especially if you machine the block and cylinder; it can also supposedly lead to wear problems within a few ten thousands of miles. Fire ringing seems to be more popular on competition motors.

O-ringing is cutting a groove in either the block or the head (not both) around the top of the cylinder, but not at the very edge of the cylinder. You put a wire "ring" in that groove, then use a stock headgasket; the wire puts more force on the stock headgasket and keeps it from moving around. O-ringing doesn't have the reputation of low-longevity and is much more popular than fire-ringing in daily drivers.

There are several people with tons of miles on firerings and who have had problems with O-rings. The machinist doing the work might have an opinion, and it's not a bad idea to do what he's comfortable with.

Studs are important on either O-rings or firerings. Even more important than studs are flat head and block surfaces; any more than a couple extra thousandths of variation and things might not last even with rings and studs.

35 PSI is a good number to get wary around. You can get away with up to 10 PSI more if you aren't using fumigants and are running relatively retarded timing.

MLS gaskets that are used by common rails can get away with murder.

 

good post

 

Begle1 at his best

 

Thanks for that post Begle, soooooooooooo anybody know of a reputable machine shop around the Columbia, SC area?

 

well i have a first gen cummins and still have stock head studs and the stock head gaskets and run 45 psi on a daily basis and have'nt had any problems granted i am planing on o-ringing my heads, but my truck will run 50 psi with ease with my twin set up but i have'nt had any problems yet

 

orings on either the head or block and studs will hold 65 pounds but you can oring both the head and the block and hold more mine has both the head and block oringed

 

so, when you oringed the block - did you do that inframe or pull the engine? That would make me very nervous.

 

i wouldnt even think of o-ringing the block, to damn hard its easer to take the head in to have it done