Motor Rebuild Help

juniort444e · Sep 22, 2011

Whats the difference between o ring and fire ring.

TrailerHauler · Sep 22, 2011

As far as I know, o rings are in the head, and fire rings are in the block.

juniort444e · Sep 22, 2011

Ok, so which one is better. Or more proven.

TrailerHauler · Sep 22, 2011

juniort444e said:
Ok, so which one is better. Or more proven.

I can't accurately answer that as I'm not familiar with o ringing a 7.3 head.
I know in the cummins world it depends on your goals. The general perception is that o rings are used for a mild build usually with twins, and Fire rings are used for a Higher HP build. Guys have used both for high HP builds with mixed results, and some say that o rings are more daily driver friendly.

I can't give any answers in stone for your build because I've never done either on a 7.3, but I figured I'd pass along my understanding of the two.

Viking · Sep 22, 2011

just dont use a gasket and weld the heads to the block....done and done!! haha

strokin'_tatsch · Sep 22, 2011

juniort444e said:
Whats the difference between o ring and fire ring.

O ring is a groove cut in head and install a metal "o ring" that will press on top of the stock fire ring that comes in the head gasket. The fire ring being the metal ring in the head gasket that seals around the cylinders

Fire rings use a deeper groove in the head or block and instead of relying on the stock fire ring in a head gasket being further squeezed by an oring, you completely cut the fire ring out of the gasket. The fire ring you install is he only seal you have, eliminating the weaker fire ring in the head gasket, allowing for higher boost numbers and more heat without blowing.

TrailerHauler · Sep 23, 2011

strokin'_tatsch said:
O ring is a groove cut in head and install a metal "o ring" that will press on top of the stock fire ring that comes in the head gasket. The fire ring being the metal ring in the head gasket that seals around the cylinders

Fire rings use a deeper groove in the head or block and instead of relying on the stock fire ring in a head gasket being further squeezed by an oring, you completely cut the fire ring out of the gasket. The fire ring you install is he only seal you have, eliminating the weaker fire ring in the head gasket, allowing for higher boost numbers and more heat without blowing.

:thumbsup: much better explanation than I gave!

TARM · Sep 23, 2011

To add to that you can also have the groove for the fire ring in both the block and head together for the maximum seal. Not sure it would be needed in your build but wanted to put that option out there.

I personally from al I have seen in ways of comments and info would always do a WOP fire ring kit with any rebuild meant for performance every time. No way I would chance a blown gasket even with using cometics for lower CP apps.

Whytry · Sep 25, 2011

Is firing ringing or o ringing able to be daily driven? I have heard that they are not and more for just competition.

PowerstrokeJunkie · Sep 25, 2011

Yes you can daily drive a engine with fire rings. I did at least. O rings are very thin rings of wire, and fire rings are somewhere around .100"

Junior did you ever think of buying a good cheap forged rod engine, put some head studs and springs in it, a new set of bottom end bearings while you're in there, and just run it? Techonolgy is coming a long way and tuning is able to keep engines together alot better than a few years back where 600hp required a fully built engine. Sure you could spend gobs of money on aftermarket internal parts and build a bulletproof engine, but crap still happens

Magnum PD · Sep 25, 2011

I worry about blowing a head gasket after my rebuild with a stock head gasket.
Wonder if I should use cometic gaskets.

juniort444e · Sep 25, 2011

Yes, that is actually what im wanting to do. I figured getting some opinions from the experts would help some.

Here is the list that im staying with, everything else i had listed before is still 50/50 right now.

Carillo rods
Mahle pistons, with bowl work valve reliefs and coated
heads port and polished
Ford rebuild kit
Gear head stage 2 cam
Stronger Valve springs

I already have on current motor,
Arp head studs, being reused on rebuilt motor
Valve springs, 910's to weak for cam
Smith bro's pushrods being reused if the are still straight

juniort444e · Sep 25, 2011

Forgot about a bed plate also. I want something to help stiffen up the bottom end and keep everything in check, without half filling the block.

Magnum PD · Sep 25, 2011

That's over $2000 by itself. Wouldn't mind having a main stud girdle myself.

juniort444e · Sep 25, 2011

Yea, but from what i hear well worth the "insurance".

Whytry · Sep 26, 2011

I might have missed it but its getting balanced isnt it?

TARM · Sep 26, 2011

You will need the fire ring kit for sure with your build or you will be blowing the gasket. IMO you should sell the ARP studs and go to the H11 for the fire ring as it needs the stronger higher tq studs from what I have read.

The only reason our stock gaskets hold so well is the seal has been cured, and aged for so long over their life. You break that seal and put new ones on even with head studs and crank up the CP as you get from big nozzles with compounds or a large single they are gonna very likely blow.

Carillo rods
Mahle pistons, with bowl work valve reliefs and coated
heads port and polished
Ford rebuild kit
Gear head stage 2 cam
Stronger Valve springs
Fire Ring Kit
Bed Plate
1/2 Filled block.

TrailerHauler · Sep 26, 2011

juniort444e said:
Forgot about a bed plate also. I want something to help stiffen up the bottom end and keep everything in check, without half filling the block.

If your dead set on something to help stiffen up the bottom of the block why not just go with a girdle. IMO a bed plate is way over kill.

juniort444e · Sep 26, 2011

I was told that a girdle helps but i would need to fill the block, which im trying to avoid. And a bed plate might be over kill but my only other option to not filling the block with a girdle on it. What i was told might be wrong, might not, i havent found out any difference yet. I will give swamps or wop a call soon to ask some questions on which way to go about it.

Fl Stroker · Sep 26, 2011

No fill here with a Girdle. Being that its a daily driver and tow rig didnt want any heat issues and having to deal with cleaning the oil cooler yearly. After speaking with Johnny and them looking at Charles rebuild and all he puts his motor through his had movement with the girdle as well. Charles has posted that the girdle is a waist as well. I figured it wouldnt hurt so girdle went in. The only way to prevent the movement is the bed plate but then again this will be your street queen with weekend duties.