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Prestige Worldwide
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Discussion Starter · #1 ·
Did a search, but not really finding the info. What pros and cons are there to fire ringing vs o-ringing the cylinder head. I have to do one or the other just not sure which. Any insight would be great!

:thud:
 

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I would like to know this also along with how much to have each done.
 

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Go for Broke
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O-ring (in the head) will last longer for the street and will hold 80+ psi boost

fire rings (in the block) are better for all out racing and will hold 120+psi of boost
 

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I have the fire rings on my 06 5.9 I believe it was around 1200.00 And just as graphic man stated the o rings will be good up to 70-80 psi boost and the fire rings will take over after that....the fire rings seal against the deck of the block instead of the gasket hope this helps you :beer
 

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i heard fire rings only last about 20000 miles.....is this true?
 

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Mark Ward
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ive never heard that. I got 10k on my new engine with fire rings and never a problem. BUT they say with fire rings you MUST make sure the engine is at operating temp before running it hard. I might be wrong on that but thats what they said at the machine shop. not sure if you have to do the same with o-rings but id imagine it would be safe practice.
 

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MI Chapter President
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O-rings in the winter or cold temps you need to get it warm before beating on it. In general its always good to get a little up to temp before thrashing the motor in cold or warm temps
 

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Tech Specialist
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rodding a cold engine is a bad idea period. With o-rings its more inportants and with fire rings its really important. The rings are designed to seal with everything expanded and at operating temp. Because fire-rings cut the sealing ring out of the HG you dont actually blow the HG, the fire ring leaks.

Vibrations are the common comcern with fire ring durability. Over time the grovves in the head/block will wear and expand and the firering won't seal. O-rings have the HG to absorb some of the vibrations and make up for small variations.

Fire-rings also require periodic retorques
 

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I took my cyl.head to the local machine shop i deal with , clean , maglaflux, valve job, reserface and new oil seals was 250.00. Then i took it to Oddys performance shop and had them oring the head 220.00. valves and seats were in great shape did not have to replace anything. Hope this priceing helps. mikeuz
 

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O-ring (in the head) will last longer for the street and will hold 80+ psi boost

fire rings (in the block) are better for all out racing and will hold 120+psi of boost
:ditto: when my head gasket goes I am going to go the o ring route because I want to be able to go down to cummins dealer and get a new head gasket and be on the road, if I ever blown it on the road. With fire ring it takes a special head gasket, to replace it. Good luck with what you decide on. :thumbsup:
 
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