6.9/7.3 idi cylinder head question

[C_Luft]

My question is, would oringing the cylinder heads on a 6.9/7.3 idi be as beneficial as it is on 6.0? I got the idea from powerstrokehelp.com's YouTube videos.

 

[79jasper]

Don't listen to anything that wack job says.
I doubt you'd ever get enough fuel to push enough boost to need oringing.
Not to mention, no one has done it, so it's new territory. Which in machinist terms = $$$$$$$$
6.0's biggest demise was not enough head bolts.
Stud a 6.9/7.3 and call it a day.
Sent from my SM-T537R4 using Tapatalk

 

[The Warden]

If memory serves, the precombustion chambers are made of such a hard metal that cutting a groove for an O-ring would be VERY cost-prohibitive.

Studs are generally enough...if you're putting in enough boost to warrant O-rings, I suspect something else will let go in short order unless you're also lowering the compression ratio significantly...

 

[icanfixall]

Because the precup enters the fire ring just the machining on a groove will require a cnc mill. To ring a head the machinst just cuts a circular groove around the head to cylinder location on both the block and head. Can't do that on the idi because of the precup in the way of that circle groove.

 

[jaluhn83]

Not only would it be very difficult, but also pointless. This is done on very high boost engines (as in 50+ psi) to help seal the fire ring - essentially it's doing the same thing as the head gasket. You're not going to get anywhere close to that kind of boost on an idi, or if you did head gasket issues would be the least of your problems.

 

[bike-maker]

I've seen this pop up a couple times, so I'll throw in my $.02 since I used to work at a machine shop that performed this operation; albeit for a different application.
We were building blown alcy motors for drag cars and boats. Copper head gaskets, o-ringed block and heads. The BHJ tool was the industry standard back then (it's been a decade or so since that job). Link to BHJ O-ring tool
The rotating cutter is universal, but it requires a big aluminum plate the shape of a head gasket to locate the cutter. The big aluminum chunk was bolted to either the heads or block using the head dowels to locate it. Grooves were cut into both the block and heads, then stainless wire was mashed into one of the grooves. The idea is that the copper head gasket gets deformed by the stainless wire (the "O-ring") and mashed up into the adjacent receiver groove; makes for one hell of a good seal.
As for the IDI, cutting the heads isn't going to happen easily; the pre-chambers are in the way. But the block could be cut pretty easily after a fixture was made to locate the cutting tool. Having the O-ring grooves in the block side, and not having the receiver grooves in the heads could very well work. The main issue as I see it is what to do for head gaskets. If the O-ring was set just outside of the fire ring, it would definitely help keep it pinched in place.
The area where I am unsure of is the sealing of the water passages. The O-ring would strengthen the seal on the combustion chamber, but at the same time it would probably weaken the seal on the water passages. The stuff I used to work on were race motors; and real race motors don't have water jackets.